<PAGE>   1
                                                                     EXHIBIT 4.6





                                  ENRON CORP.,
                                    ISSUER,

                                      AND

                       THE CHASE MANHATTAN BANK, TRUSTEE

                             ______________________

                                   INDENTURE

                         DATED AS OF NOVEMBER 21, 1996

                            ________________________

                         7.75% SUBORDINATED DEBENTURES
                                    DUE 2016
<PAGE>   2
                 Certain Sections of this Indenture relating to
                        Sections 310 through 318 of the
                          Trust Indenture Act of 1939

<TABLE>
<CAPTION>
Trust Indenture                                                                                                Indenture
Act Section                                                                                                      Section
-----------                                                                                                      -------
<S>                                                                                                        <C>
Section 310(a)(1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 609
          (a)(2)  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 609
          (a)(3)  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  Not Applicable
          (a)(4)  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  Not Applicable
          (b)     . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  608, 610
Section 311(a)    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 613
          (b)     . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 613
Section 312(a)    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 701
                  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  702(a)
         (b)      . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  702(b)
         (c)      . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  702(c)
Section 313(a)    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  703(a)
         (a)(4)   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101, 1004
         (b)      . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  703(a)
         (c)      . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  703(a)
         (d)      . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  703(b)
Section 314(a)    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 704
         (b)      . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  Not Applicable
         (c)(1)   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
         (c)(2)   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
         (c)(3)   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  Not Applicable
         (d)      . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  Not Applicable
         (e)      . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Section 315(a)    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 601
         (b)      . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 602
         (c)      . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 601
         (d)      . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 601
         (e)      . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 514
Section 316(a)    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
         (a)(1)(A). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 502
                  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 512
         (a)(1)(B). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 513
         (a)(2)   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  Not Applicable
         (b)      . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 508
         (c)      . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  104(c)
Section 317(a)(1) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 503
         (a)(2)   . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 504
         (b)      . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  1003
Section 318(a)    . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
</TABLE>

___________
Note:  This reconciliation and tie shall not, for any purpose, be deemed to be
       a part of the Indenture.
 
<PAGE>   3
                               TABLE OF CONTENTS

<TABLE>
<CAPTION>
                                                                                                                    Page 
                                                                                                                    -----
         <S>           <C>                                                                                             <C>
                                                       ARTICLE ONE
                                             Definitions and other Provisions
                                                  of General Application

         SECTION 101.  Definitions  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
         SECTION 102.  Compliance Certificates and Opinions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
         SECTION 103.  Form of Documents Delivered to Trustee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
         SECTION 104.  Acts of Holders; Record Dates  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
         SECTION 105.  Notices, Etc., to Trustee and the Company  . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
         SECTION 106.  Notice to Holders; Waiver  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  10
         SECTION 107.  Conflict with Trust Indenture Act  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  10
         SECTION 108.  Effect of Headings and Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . .  10
         SECTION 109.  Successors and Assigns . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  10
         SECTION 110.  Separability Clause  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  11
         SECTION 111.  Benefits of Indenture  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  11
         SECTION 112.  Governing Law  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  11
         SECTION 113.  Legal Holidays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  11

                                                       ARTICLE TWO
                                                      Security Forms

         SECTION 201.  Forms Generally  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  11
         SECTION 202.  Form of Face of Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  12
         SECTION 203.  Form of Reverse of Security  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  14
         SECTION 204.  Form of Trustee's Certificate of Authentication  . . . . . . . . . . . . . . . . . . . . . . .  16

                                                      ARTICLE THREE
                                                      The Securities

         SECTION 301.  Title and Terms  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  16
         SECTION 302.  Denominations  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  17
         SECTION 303.  Execution, Authentication, Delivery and Dating . . . . . . . . . . . . . . . . . . . . . . . .  17
         SECTION 304.  Temporary Securities . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  18
         SECTION 305.  Registration, Registration of Transfer and Exchange  . . . . . . . . . . . . . . . . . . . . .  18
         SECTION 306.  Mutilated, Destroyed, Lost and Stolen Securities . . . . . . . . . . . . . . . . . . . . . . .  19
         SECTION 307.  Payment of Interest; Interest Rights Preserved . . . . . . . . . . . . . . . . . . . . . . . .  20
</TABLE>





                                       i
<PAGE>   4
<TABLE>
         <S>           <C>                                                                                             <C>
         SECTION 308.  Persons Deemed Owners  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  21
         SECTION 309.  Cancellation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  21
         SECTION 310.  Computation of Interest  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  21

                                                       ARTICLE FOUR
                                                Satisfaction and Discharge

         SECTION 401.  Satisfaction and Discharge of Indenture  . . . . . . . . . . . . . . . . . . . . . . . . . . .  22
         SECTION 402.  Application of Trust Money . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  23

                                                       ARTICLE FIVE
                                                         Remedies

         SECTION 501.  Events of Default  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  23
         SECTION 502.  Acceleration of Maturity; Rescission and Annulment . . . . . . . . . . . . . . . . . . . . . .  24
         SECTION 503.  Collection of Indebtedness and Suits for Enforcement by Trustee  . . . . . . . . . . . . . . .  24
         SECTION 504.  Trustee May File Proofs of Claim . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  25
         SECTION 505.  Trustee May Enforce Claims Without Possession of Securities  . . . . . . . . . . . . . . . . .  25
         SECTION 506.  Application of Money Collected . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  26
         SECTION 507.  Limitation on Suits  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  26
         SECTION 508.  Unconditional Right of Holders to Receive Principal and Interest . . . . . . . . . . . . . . .  27
         SECTION 509.  Restoration of Rights and Remedies . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  27
         SECTION 510.  Rights and Remedies Cumulative . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  27
         SECTION 511.  Delay or Omission Not Waiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  27
         SECTION 512.  Control by Holders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  27
         SECTION 513.  Waiver of Past Defaults  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  28
         SECTION 514.  Undertaking for Costs  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  28

                                                       ARTICLE SIX
                                                       The Trustee

         SECTION 601.  Certain Duties and Responsibilities  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  29
         SECTION 602.  Notice of Defaults . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  29
         SECTION 603.  Certain Rights of Trustee  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  29
         SECTION 604.  Not Responsible for Recitals or Issuance of Securities . . . . . . . . . . . . . . . . . . . .  30
         SECTION 605.  May Hold Securities  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  31
         SECTION 606.  Money Held in Trust  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  31
         SECTION 607.  Compensation and Reimbursement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  31
         SECTION 608.  Disqualification; Conflicting Interests  . . . . . . . . . . . . . . . . . . . . . . . . . . .  32
         SECTION 609.  Corporate Trustee Required; Eligibility  . . . . . . . . . . . . . . . . . . . . . . . . . . .  32
</TABLE>





                                       ii
<PAGE>   5
<TABLE>
         <S>          <C>                                                                                              <C>
         SECTION 610.  Resignation and Removal; Appointment of Successor  . . . . . . . . . . . . . . . . . . . . . .  32
         SECTION 611.  Acceptance of Appointment by Successor . . . . . . . . . . . . . . . . . . . . . . . . . . . .  33
         SECTION 612.  Merger, Conversion, Consolidation or Succession to Business  . . . . . . . . . . . . . . . . .  33
         SECTION 613.  Preferential Collection of Claims Against Company  . . . . . . . . . . . . . . . . . . . . . .  34

                                                      ARTICLE SEVEN
                                          Holders' Lists and Reports by Trustee

         SECTION 701.  Company to Furnish Trustee Names and Addresses of Holders  . . . . . . . . . . . . . . . . . .  34
         SECTION 702.  Preservation of Information; Communications to Holders . . . . . . . . . . . . . . . . . . . .  34
         SECTION 703.  Reports by Trustee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  35

                                                      ARTICLE EIGHT
                                   Consolidation, Merger, Conveyance, Transfer or Lease

         SECTION 801.  Company May Consolidate, Etc., Only on Certain Terms . . . . . . . . . . . . . . . . . . . . .  35
         SECTION 802.  Successor Substituted  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  36

                                                       ARTICLE NINE
                                                 Supplemental Indentures

         SECTION 901.  Supplemental Indentures Without Consent of Holders . . . . . . . . . . . . . . . . . . . . . .  36
         SECTION 902.  Supplemental Indentures with Consent of Holders  . . . . . . . . . . . . . . . . . . . . . . .  37
         SECTION 903.  Execution of Supplemental Indentures . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  37
         SECTION 904.  Effect of Supplemental Indentures  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  38
         SECTION 905.  Conformity with Trust Indenture Act  . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  38

                                                       ARTICLE TEN
                                        Covenants; Representations and Warranties

         SECTION 1001.  Payment of Principal and Interest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  38
         SECTION 1002.  Maintenance of Office or Agency . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  38
         SECTION 1003.  Money for Security Payments to Be Held in Trust . . . . . . . . . . . . . . . . . . . . . . .  39
         SECTION 1004.  Reports by the Company  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  39
         SECTION 1005.  Negative Pledge and Exceptions Thereto  . . . . . . . . . . . . . . . . . . . . . . . . . . .  39
         SECTION 1006.  Statement as to Compliance; Notice of Certain Events of Default . . . . . . . . . . . . . . .  42
</TABLE>





                                      iii
<PAGE>   6
<TABLE>
         <S>            <C>                                                                                            <C>
                                                      ARTICLE ELEVEN
                                               Subordination of Securities

         SECTION 1101.  Securities Subordinate to Senior Indebtedness . . . . . . . . . . . . . . . . . . . . . . . .  43
         SECTION 1102.  Payment Over of Proceeds upon Dissolution, etc. . . . . . . . . . . . . . . . . . . . . . . .  43
         SECTION 1103.  No Payment When Senior Indebtedness in Default  . . . . . . . . . . . . . . . . . . . . . . .  44
         SECTION 1104.  Payment Permitted If No Default . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  45
         SECTION 1105.  Subrogation to Rights of Holders of Senior Indebtedness . . . . . . . . . . . . . . . . . . .  45
         SECTION 1106.  Provisions Solely to Define Relative Rights . . . . . . . . . . . . . . . . . . . . . . . . .  45
         SECTION 1107.  Trustee to Effectuate Subordination . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  46
         SECTION 1108.  No Waiver of Subordination Provisions . . . . . . . . . . . . . . . . . . . . . . . . . . . .  46
         SECTION 1109.  Notice to Trustee . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  46
         SECTION 1110.  Reliance on Judicial Order or Certificate of Liquidating Agent  . . . . . . . . . . . . . . .  47
         SECTION 1111.  Rights of Trustee as a Holder of Senior Indebtedness; Preservation of
                                  Trustee's Rights  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  47
         SECTION 1112.  Article Applicable to Paying Agents . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  48

                                                      ARTICLE TWELVE
                                                 Redemption of Securities

         SECTION 1201.  Optional Redemption . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  48
         SECTION 1202.  Applicability of Article  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  48
         SECTION 1203.  Authorization for Redemption; Notice to Trustee . . . . . . . . . . . . . . . . . . . . . . .  48
         SECTION 1204.  Selection by Trustee of Securities to Be Redeemed . . . . . . . . . . . . . . . . . . . . . .  49
         SECTION 1205.  Notice of Redemption  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  49
         SECTION 1206.  Deposit of Redemption Price . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  50
         SECTION 1207.  Securities Payable on Redemption Date . . . . . . . . . . . . . . . . . . . . . . . . . . . .  50
         SECTION 1208.  Securities Redeemed in Part . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .  50
</TABLE>





                                       iv
<PAGE>   7
         INDENTURE, dated as of November 21, 1996, by and between Enron Corp.,
a corporation duly organized and validly existing under the laws of the State
of Delaware (the "Company"), and The Chase Manhattan Bank, a New York banking
corporation (the "Trustee").

                            RECITALS OF THE COMPANY

         The Company has duly authorized the execution and delivery of this
Indenture to provide for the issuance of its 7.75% Subordinated Debentures due
2016 (the "Securities") as herein provided.

         All things necessary to make this Indenture a valid agreement of the
Company, in accordance with its terms, have been done.

                   NOW THEREFORE, THIS INDENTURE WITNESSETH:

         For and in consideration of the premises and the purchase of the
Securities by the Holders thereof, it is mutually covenanted and agreed as
follows for the equal and ratable benefit of the Holders of the Securities:

                                  ARTICLE ONE

                        Definitions and other Provisions
                             of General Application

SECTION 101.  Definitions.

         For all purposes of this Indenture, except as otherwise expressly
provided or unless the context otherwise requires:

         (1) the terms defined in this Article have the meanings assigned to
them in this Article and include the plural as well as the singular;

         (2) all other terms used herein which are defined in the Trust
Indenture Act, either directly or by reference therein, have the meanings
assigned to them therein;

         (3) all accounting terms not otherwise defined herein have the
meanings assigned to them in accordance with generally accepted accounting
principles; and

         (4) the words "herein," "hereof" and "hereunder" and other words of
similar import refer to this Indenture as a whole and not to any particular
Article, Section or other subdivision.

         "Act," when used with respect to any Holder, has the meaning specified
in Section 104.

         "Additional Interest" means interest that shall accrue on any interest
on the Securities that is in arrears for more than one quarter or not paid
during an Extension Period, which in either case shall accrue at the rate of
7.75% per annum compounded quarterly.
<PAGE>   8
         "Affiliate" of any specified Person means any other Person directly or
indirectly controlling or controlled by or under direct or indirect common
control with such specified Person.  For the purposes of this definition,
"control" when used with respect to any specified Person means the power to
direct the management and policies of such Person, directly or indirectly,
whether through the ownership of voting securities, by contract or otherwise;
and the terms "controlling" and "controlled" have meanings correlative to the
foregoing.

         "Board of Directors" means either the board of directors of the
Company or any duly authorized committee of that board.

         "Board Resolution" means a copy of a resolution certified by the
Secretary or an Assistant Secretary of the Company to have been duly adopted by
certification, and delivered to the Trustee.
         "Business Day" means a day other than a day on which banking
institutions in the City of New York are authorized or required by law to
close.

         "Commission" means the Securities and Exchange Commission, as from
time to time constituted, created under the Securities Exchange Act of 1934,
or, if at any time after the execution of this instrument such Commission is
not existing and performing the duties now assigned to it under the Trust
Indenture Act, then the body performing such duties at such time.

         "Company" means the Person named as the "Company" in the first
paragraph of this instrument until a successor Person shall have become such
pursuant to the applicable provisions of this Indenture, and thereafter
"Company" shall mean such successor Person.

         "Company Request" or "Company Order" means a written request or order
signed in the name of the Company by its Chairman, a Vice Chairman, its
President or a Vice President and delivered to the Trustee.

         "Consolidated Net Tangible Assets" means total assets less (a) total
current liabilities (excluding indebtedness due within 12 months) and (b)
goodwill, patents and trademarks, all as reflected in the Company's audited
consolidated balance sheet preceding the date of a determination under the last
paragraph of Section 1005.

         "Corporate Trust Office" means the principal office of the Trustee in
New York, New York, at which at any particular time its corporate trust
business shall be administered and which at the date of this Indenture is 450
West 33rd Street - 15th Floor, New York, New York 10001.

         "Defaulted Interest" has the meaning specified in Section 307.

         "Event of Default" has the meaning specified in Section 501.

         "Extension Period" has the meaning specified in Section 301.





                                       2
<PAGE>   9
         "Federal Bankruptcy Code" means the Bankruptcy Act of Title 11 of the
United States Code, as amended from time to time.

         "Funded Debt" as applied to any corporation means all indebtedness
incurred, created, assumed or guaranteed by such corporation, or upon which it
customarily pays interest charges, which matures, or is renewable by such
corporation to a date, more than one year after the date as of which Funded
Debt is being determined; provided, however, that the term "Funded Debt" shall
not include (i) indebtedness incurred in the ordinary course of business
representing borrowings, regardless of when payable, of such corporation from
time to time against, but not in excess of the face amount of, its installment
accounts receivable for the sale of appliances and equipment sold in the
regular course of business or (ii) advances for construction and security
deposits received by such corporation in the ordinary course of business

         "General Partner" means the Company, in its capacity as general
partner of the Partnership.  "Holder" means a Person in whose name a Security is
registered in the Security Register.

         "Indenture" means this instrument as originally executed or as it may
from time to time be supplemented or amended by one or more indentures
supplemental hereto entered into pursuant to the applicable provisions hereof,
including, for all purposes of this instrument and any such supplemental
indenture, the provisions of the Trust Indenture Act that are deemed to be a
part of and govern this instrument and any such supplemental indenture,
respectively.

         "Interest Payment Date," when used with respect to any installment of
interest on a Security, means the date specified in such Security as the fixed
date on which an installment of interest with respect to the Securities is due
and payable.

         "Limited Partnership Agreement" means the Amended and Restated
Agreement of Limited Partnership, dated as of November 21, 1996, of the
Partnership, as amended, modified or otherwise supplemented from time to time.

         "Maturity," when used with respect to any Security, means the date on
which the original of such Security becomes due and payable as therein or
herein provided, whether at the Stated Maturity or by declaration of
acceleration, call for redemption or otherwise.

         "Officers' Certificate" means a certificate signed by (i) the
Chairman, a Vice Chairman, the President, a Vice President, or the Treasurer of
the Company and (ii) the Secretary or an Assistant Secretary of the Company and
delivered to the Trustee; provided, however, that such certificate may be
signed by two of the officers or directors listed in clause (i) above in lieu
of being signed by one of such officers or directors listed in such clause (i)
and one of the officers listed in clause (ii) above. One of the officers
signing an Officer's Certificate given pursuant to Section 1004 shall be the
principal executive, financial or accounting officer of the Company.  Any
Officers' Certificate delivered with respect to compliance with a condition or
covenant provided for in this Indenture shall include:





                                       3
<PAGE>   10
         (a) a statement that each officer signing the Officers' Certificate
has read the covenant or condition and the definitions relating thereto;

         (b) a brief statement of the nature and scope of the examination or
investigation undertaken by each officer in rendering the Officers'
Certificate;

         (c) a statement that each such officer has made such examination or
investigation as, in such officer's opinion, is necessary to enable such
officer to express an informed opinion as to whether or not such covenant or
condition has been complied with;

         (d) a statement as to whether, in the opinion of each such officer,
such condition or covenant has been complied with; and

         (e) a statement that one of the officers signing such Officers'
Certificate is the principal executive, financial or accounting officer of the
Company.

         "Opinion of Counsel" means a written opinion of counsel, who may be
counsel for the Company.

         "Outstanding," when used with respect to Securities, means, as of the
date of determination, all Securities theretofore authenticated and delivered
under this Indenture, except: (i) Securities theretofore canceled by the
Trustee or delivered to the Trustee for cancellation; (ii) Securities for whose
payment or redemption money in the necessary amount has been theretofore
deposited with the Trustee or any Paying Agent (other than the Company) in
trust or set aside and segregated in trust by the Company (if the Company shall
act as its own Paying Agent) for the Holders of such Securities; provided that,
if such Securities are to be redeemed, notice of such redemption has been duly
given pursuant to this Indenture or provision therefor satisfactory to the
Trustee has been made; and (iii) Securities which have been paid pursuant to
Section 401, or in exchange for or in lieu of which other Securities have been
authenticated and delivered pursuant to this Indenture, other than any such
Securities in respect of which there shall have been presented to the Trustee
proof satisfactory to it that such Securities are held by a bona fide purchaser
in whose hands such Securities are valid obligations of the Company.

         "Partnership" means Enron Preferred Funding, L.P., a Delaware limited
partnership, and any successor thereto.

         "Partnership Investment Company Event" means that the General Partner
shall have requested and received an opinion of nationally recognized
independent legal counsel experienced in such matters to the effect that as a
result of the occurrence on or after the date hereof of a change in law or
regulation or a change in interpretation or application of law or regulation by
any legislative body, court, governmental agency or regulatory authority, the
Partnership is or will be considered an "investment company" which is required
to be registered under the Investment Company Act of 1940.

         "Partnership Preferred Securities" means the limited partner interests
issued pursuant to the Limited Partnership Agreement.





                                       4
<PAGE>   11
         "Partnership Special Event" means either a Partnership Investment
Company Event or a Partnership Tax Event.

         "Partnership Tax Event" means that the Company, as the general partner
of the Partnership, shall have requested and received an opinion of nationally
recognized independent tax counsel experienced in such matters to the effect
that there has been a Tax Action resulting in there being more than an
insubstantial risk that (i) the Partnership is, or will be subject to United
States federal income tax with respect to income accrued or received on the
Affiliate Investment Instruments or the Eligible Debt Securities (each as
defined in the Limited Partnership Agreement), (ii) the Partnership is, or will
be subject to more than a de minimis amount of other taxes, duties or other
governmental charges or (iii) interest payable by one or more of the obligors
with respect to the Affiliate Investment Instruments to the Partnership is not,
or will not be, deductible by the Company for United States federal income tax
purposes.

         "Paying Agent" means any Person authorized by the Company to pay the
principal of or interest on any Securities on behalf of the Company, which
shall initially be The Chase Manhattan Bank.

         "Person" means any individual, corporation, partnership, joint
venture, trust, limited liability company or corporation, unincorporated
organization or government or any agency or political subdivision thereof.

         "Predecessor Security" of any particular Security means every previous
Security evidencing all or a portion of the same debt as that evidenced by such
particular Security; and, for the purposes of this definition, any Security
authenticated and delivered under Section 306 in exchange for or in lieu of a
mutilated, destroyed, lost or stolen Security shall be deemed to evidence the
same debt as the mutilated, destroyed, lost or stolen Security.

         "Preferred Securities" means the Partnership Preferred Securities and
the Trust Preferred Securities.

         "Principal Property" means any oil or gas pipeline, gas processing
plant or chemical plant located in the United States, except any such property,
pipeline or plant that in the opinion of the Board of Directors is not of
material importance to the total business conducted by the Company and its
Subsidiaries. "Principal Property" shall not include any oil or gas property or
the production or any proceeds of production from an oil or gas producing
property or the production or any proceeds of production of gas processing
plants or oil or gas or petroleum products in any pipeline.

         "Redemption Date," when used with respect to any Security to be
redeemed, means the date fixed for such redemption by or pursuant to this
Indenture.

         "Redemption Price," when used with respect to any Security to be
redeemed, means the price at which it is to be redeemed pursuant to this
Indenture.





                                       5
<PAGE>   12
         "Regular Record Date" for the interest payable on any Interest Payment
Date means the Business Day next preceding such Interest Payment Date.

         "Representative" means an indenture trustee or other trustee, agent or
representative for an issue of Senior Indebtedness.

         "Responsible Officer," when used with respect to the Trustee, means
any officer within the Corporate Trust Office including any Vice President,
Assistant Vice President, Secretary, Assistant Secretary or any other officer
of the Trustee customarily performing functions similar to those performed by
any of the above designated officers and also, with respect to a particular
matter, any other officer to whom such matter is referred because of such
officer's knowledge and familiarity with the particular subject.

         "Securities" has the meaning specified in the Recitals to this
instrument.

         "Security Register" and "Security Registrar" have the respective
meanings specified in Section 305.

         "Senior Indebtedness" means the principal of, premium, if any,
interest on and any other payment due pursuant to any of the following, whether
outstanding at the date hereof or hereafter incurred, created or assumed: (i)
all indebtedness of the Company (other than any obligations to trade creditors)
evidenced by notes, debentures, bonds or other securities sold by the Company
for money borrowed and capitalized lease obligations; (ii) all indebtedness of
others of the kinds described in the preceding clause (i) assumed or guaranteed
in any manner by the Company or in effect guaranteed by the Company; and (iii)
all renewals, extensions or refundings of indebtedness of the kinds described
in either of the preceding clauses (i) or (ii), unless, in the case of any
particular indebtedness, capitalized lease obligation, guarantee, renewal,
extension or refunding, the instrument creating or evidencing the same or the
assumption or guarantee of the same expressly provides that such indebtedness,
renewal, extension or refunding is subordinated to or is pari passu with the
Securities.

         "Special Record Date" for the payment of any Defaulted Interest means
a date fixed by the Trustee pursuant to Section 307.

         "Stated Maturity," when used with respect to any Security or any
installment of interest thereon, means the date specified in such Security as
the fixed date on which the principal, together with any accrued and unpaid
interest (including Additional Interest), of such Security or such installment
of interest is due and payable.

         "Subsidiary" means any Person a majority of the equity ownership or
the Voting Stock of which is at the time owned, directly or indirectly, by the
Company or by one or more other Subsidiaries, or by the Company and one or more
other Subsidiaries.  For the purposes of this definition, "voting stock" means
stock which ordinarily has voting power for the election of directors, whether
at all times or only so long as no senior class of stock has such voting power
by reason of any contingency.





                                       6
<PAGE>   13
         "Tax Action" means that there has been (a) an amendment to, change in
or announced proposed change in the laws (or any regulations thereunder) of the
United States or any political subdivision or taxing authority thereof or
therein, (b) a judicial decision interpreting, applying, or clarifying such
laws or regulations, (c) an administrative pronouncement or action that
represents an official position (including a clarification of an official
position) of the governmental authority or regulatory body making such
administrative pronouncement or taking such action, or (d) a threatened
challenge asserted in connection with an audit of the Company or any of its
Subsidiaries, the Partnership, or the Trust, or a threatened challenge asserted
in writing in connection with any other taxpayer that has raised capital
through the issuance of securities that are substantially similar to the
Securities, the Partnership Preferred Securities, or the Trust Preferred
Securities, which amendment or change is adopted or which decision or
pronouncement is announced or which action, clarification or challenge occurs
on or after the date of this Indenture.

         "Trust" means Enron Capital Trust I, a Delaware business trust, and
any successor thereto.

         "Trust Agreement" means the Amended and Restated Declaration of Trust
of the Trust dated November 18, 1996 among Enron Corp., as Sponsor, and the
trustees named therein.

         "Trustee" means the Person named as the "Trustee" in the first
paragraph of this instrument until a successor Trustee shall have become such
pursuant to the applicable provisions of this Indenture, and thereafter
"Trustee" shall mean such successor Trustee.

         "Trust Indenture Act" means the Trust Indenture Act of 1939 as in
force at the date as of which this instrument was executed; provided, however,
that in the event the Trust Indenture Act of 1939 is amended after such date,
"Trust Indenture Act" means, to the extent required by any such amendment, the
Trust Indenture Act of 1939 as so amended.

         "Trust Preferred Securities" means the 8.30% Trust Originated
Preferred Securities, liquidation amount $25 per Trust Preferred Security,
issued pursuant to the Trust Agreement.

         "Vice President," when used with respect to the Company or the
Trustee, means any vice president, whether or not designated by a number or a
word or words added before or after the title "vice president".

SECTION 102.  Compliance Certificates and Opinions.

         Upon any application or request by the Company to the Trustee to take
any action under any provision of this Indenture, the Company shall furnish to
the Trustee an Officers' Certificate stating that all conditions precedent, if
any, provided for in this Indenture relating to the proposed action have been
complied with.

         Every certificate or opinion with respect to compliance with a
condition or covenant provided for in this Indenture shall include:





                                       7
<PAGE>   14
         (1)     a statement that each individual signing such certificate or
opinion has read such covenant or condition and the definitions herein relating
thereto;

         (2)     a brief statement as to the nature and scope of the
examination or investigation upon which the statements or opinions contained in
such certificate or opinion are based;

         (3)     a statement that, in the opinion of each such individual, he
has made such examination or investigation as is necessary to enable him to
express an informed opinion as to whether or not such covenant or condition has
been complied with; and

         (4)     a statement as to whether, in the opinion of each individual,
such condition or covenant has been complied with.

SECTION 103.  Form of Documents Delivered to Trustee.

         In any case where several matters are required to be certified by, or
covered by an opinion of, any specified Person, it is not necessary that all
such matters be certified by, or covered by the opinion of, only one such
Person, or that they be so certified or covered by only one document, but one
such Person may certify or give an opinion with respect to some matters and one
or more other such Persons as to other matters, and any such Person may certify
or give an opinion as to such matters in one or several documents.

         Any certificate or opinion of an officer of the Company may be based,
insofar as it relates to legal matters, upon a certificate or opinion of, or
representations by, counsel, unless such officer knows, or in the exercise of
reasonable care should know, that the certificate or opinion or representations
with respect to the matters upon which his certificate or opinion is based are
erroneous.  Any such certificate or opinion of counsel may be based, insofar as
it relates to factual matters, upon a certificate or opinion of, or
representations by, an officer or officers of the Company stating that the
information with respect to such factual matters is in the possession of the
Company, unless such counsel knows, or in the exercise of reasonable care
should know, that the certificate or opinion or representations with respect to
such matters are erroneous.

         Where any Person is required to make, give or execute two or more
applications, requests, consents, certificates, statements, opinions or other
instruments under this Indenture, they may, but need not, be consolidated and
form any instrument.

SECTION 104.  Acts of Holders; Record Dates.

         (a) Any request, demand, authorization, direction, notice, consent,
waiver or other action provided by this Indenture to be given or taken by
Holders may be embodied in and evidenced by one or more instruments of
substantially similar tenor signed by such Holders in person or by agent duly
appointed in writing; and, except as herein otherwise expressly provided, such
action shall become effective when such instrument or instruments are delivered
to the Trustee and, where it is hereby expressly required, to the Company.
Such instrument or instruments (and the action embodied therein and evidenced
thereby) are herein sometimes referred to as the "Act" of the





                                       8
<PAGE>   15
Holders signing such instrument or instruments.  Proof of execution of any such
instrument or of a writing appointing any such agent shall be sufficient for
any purpose of this Indenture and (subject to Section 601) conclusive in favor
of the Trustee and the Company, if made in the manner provided in this Section.

         (b) The fact and date of the execution by any Person of any such
instrument or writing may be proved by the affidavit of a witness of such
execution or by a certificate of a notary public or other officer authorized by
law to take acknowledgments of deeds, certifying that the individual signing
such instrument or writing acknowledged to him the execution thereof.  Where
such execution is by a signer acting in a capacity other than his individual
capacity, such certificate or affidavit shall also constitute sufficient proof
of his authority.  The fact and date of the execution of any such instrument or
writing or the authority of the Person executing the same, may also be proved
in any other manner which the Trustee deems sufficient.

         (c) The Company may, in the circumstances permitted by the Trust
Indenture Act, fix any day as the record date for the purpose of determining
the Holders entitled to give or take any request, demand, authorization,
direction, notice, consent, waiver or other action, or to vote on any action,
authorized or permitted to be given or taken by Holders.  If not set by the
Company prior to the first solicitation of a Holder made by any Person in
respect of any such action, or, in the case of any such vote, prior to such
vote, the record date for any such action or vote shall be the 30th day (or, if
later, the date of the most recent list of Holders required to be provided
pursuant to Section 701) prior to such first solicitation or vote, as the case
may be.  With regard to any record date, only the Holders on such date (or
their duly designated proxies) shall be entitled to give or take, or vote on,
the relevant action.

         (d) The ownership of Securities shall be proved by the Security
Register.

         (e) Any request, demand, authorization, direction, notice, consent,
waiver or other Act of the Holder of any Security shall bind every future
Holder of the same Security and the Holder of every Security issued upon the
registration of transfer thereof or in exchange therefor or in lieu thereof in
respect of anything done, omitted or suffered to be done by the Trustee or the
Company in reliance thereon, whether or not notation of such action is made
upon such Security.

SECTION 105.  Notices, Etc., to Trustee and the Company.

         Any request, demand, authorization, direction, notice, consent, waiver
or Act of Holders or other document provided or permitted by this Indenture to
be made upon, given or furnished to, or filed with,

         (1) the Trustee by any Holder or by the Company shall be sufficient
for every purpose hereunder if made, given, furnished or filed in writing to or
with the Trustee at its Corporate Trust Office, Attention: Global Trust
Services, or

         (2) the Company by the Trustee or by any Holder shall be sufficient
for every purpose hereunder (unless otherwise herein expressly provided) if in
writing and mailed, first-class postage





                                       9
<PAGE>   16
prepaid, to the Company addressed to it at the address of its principal office
specified below or at any other address previously furnished in writing to the
Trustee by the Company.

         If to the Company to:

                 Enron Corp.
                 1400 Smith Street
                 Houston, Texas 77002
                 Attention: Treasurer

SECTION 106.  Notice to Holders; Waiver.

         Where this Indenture provides for notice to Holders of any event, such
notice shall be sufficiently given (unless otherwise herein expressly provided)
if in writing and mailed, first-class postage prepaid, to each Holder affected
by such event, at his address as it appears in the Security Register, not later
than the latest date (if any), and not earlier than the earliest date (if any),
prescribed for the giving of such notice.  In any case where notice to Holders
is given by mail, neither the failure to mail such notice, nor any defect in a
notice so mailed, to any particular Holder shall affect the sufficiency of such
notice with respect to other Holders.  Where this Indenture provides for notice
in any manner, such notice may be waived in writing by the Person entitled to
receive such notice, either before or after the event, and such waiver shall be
the equivalent of such notice.  Waivers of notice by Holders shall be filed
with the Trustee, but such filing shall not be a condition precedent to the
validity of any action taken in reliance upon such waiver.

         In case by reason of the suspension of regular mail service or by
reason of any other cause it shall be impracticable to give such notice by
mail, then such notification as shall be made with the approval of the Trustee
shall constitute a sufficient notification for every purpose hereunder.

SECTION 107.  Conflict with Trust Indenture Act.

         If any provision hereof limits, qualifies or conflicts with a
provision of the Trust Indenture Act that is required under such Act to be a
part of and govern this Indenture, the latter provision shall control.  If any
provision of this Indenture modifies or excludes any provision of the Trust
Indenture Act that may be so modified or excluded, the latter provision shall
be deemed to apply to this Indenture as so modified or to be excluded, as the
case may be.

SECTION 108.  Effect of Headings and Table of Contents.

         The Article and Section headings herein and the Table of Contents are
for convenience only and shall not affect the construction hereof.

SECTION 109.  Successors and Assigns.

         The Company will have the right at all times to assign any of its
rights or obligations under this Indenture to a direct or indirect wholly-owned
Subsidiary, provided that, in the event of any such





                                       10
<PAGE>   17
assignment, the Company will remain liable for all such obligations.  Subject
to the foregoing, this Indenture is binding upon and inures to the benefit of
the parties hereto and their respective successors and assigns. This Indenture
may not otherwise be assigned by the parties hereto.

SECTION 110.  Separability Clause.

         In case any provision in this Indenture or in the Securities shall be
invalid, illegal or unenforceable, the validity, legality and enforceability of
the remaining provisions shall not in any way be affected or impaired thereby.


SECTION 111.  Benefits of Indenture.

         Nothing in this Indenture or in the Securities, express or implied,
shall give to any Person, other than the parties hereto and their successors
hereunder, the holders of Senior Indebtedness, the holders of Preferred
Securities (to the extent provided herein) and the Holders of Securities, any
benefit or any legal or equitable right, remedy or claim under this Indenture.

SECTION 112.  Governing Law.

         THIS INDENTURE AND THE SECURITIES SHALL BE GOVERNED BY AND CONSTRUED
IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK.

SECTION 113.  Legal Holidays.

         In any case where any Interest Payment Date, Redemption Date or Stated
Maturity of any Security shall not be a Business Day, then (notwithstanding any
other provision of this Indenture or of the Securities) payment of interest or
principal of the Securities shall be made on the next succeeding day which is a
Business Day (and without any interest or other payment in respect of any such
delay) except that, if such Business Day is in the next succeeding calendar
year, such payment of interest or principal of the Securities, as the case may
be, shall be made on the immediately preceding Business Day (and without any
reduction in interest or principal in respect of such early payment).

                                  ARTICLE TWO

                                 Security Forms

SECTION 201.  Forms Generally.

         The Securities and the Trustee's certificates of authentication shall
be in substantially the forms set forth in this Article, with such appropriate
insertions, omissions, substitutions and other variations as are required or
permitted by this Indenture, and may have such letters, numbers or other marks
of identification and such legends or endorsements placed thereon as may be
required to comply with the rules of any securities exchange or as may,
consistently herewith, be determined by the officers executing such Securities,
as evidenced by their execution of the Securities.





                                       11
<PAGE>   18
         The definitive Securities shall be printed, lithographed or engraved
or produced by any combination of these or other methods, all as determined by
the officers executing such Securities, as evidenced by their execution of such
Securities.

SECTION 202.  Form of Face of Security.

                                  ENRON CORP.

                         7.75% Subordinated Debenture,
                                    Due 2016

No. _____________                                                      $________

         Enron Corp., a corporation duly organized and existing under the laws
of the State of Delaware (herein called the "Company," which term includes any
successor corporation under the Indenture hereinafter referred to), for value
received, hereby promises to pay to ________________, or registered assigns,
the principal sum of ________ DOLLARS ($________) on September 30, 2016 and to
pay interest on said principal sum from November 21, 1996 or from the most
recent interest payment date (each such date, an "Interest Payment Date") to
which interest has been paid or duly provided for, quarterly (subject to
deferral as set forth herein) in arrears on March 31, June 30, September 30 and
December 31 of each year, commencing December 31, 1996, at the rate of 7.75%
per annum plus Additional Interest, if any, until the principal hereof shall
have become due and payable, and on any overdue principal. The amount of
interest payable for any period will be computed on the basis of twelve 30-day
months and a 360-day year.  In the event that any date on which interest is
payable on this Security is not a Business Day, then a payment of the interest
payable on such date will be made on the next succeeding day which is a
Business Day (and without any interest or other payment in respect of any such
delay), except that, if such Business Day is in the next succeeding calendar
year, such payment shall be made on the immediately preceding Business Day, in
each case with the same force and effect as if made on the date the payment was
originally payable.  A "Business Day" shall mean any day other than a day on
which banking institutions in the City of New York are authorized or required
by law to remain closed.  The interest installment so payable, and punctually
paid or duly provided for, on any Interest Payment Date will, as provided in
the Indenture, be paid to the Person in whose name this Security (or one or
more Predecessor Securities, as defined in the Indenture) is registered at the
close of business on the Regular Record Date for such interest installment,
which shall be the close of business on the Business Day next preceding such
Interest Payment Date.  Any such interest installment not so punctually paid or
duly provided for shall forthwith cease to be payable to the Holder on such
Regular Record Date and may either be paid to the Person in whose name this
security (or one or more Predecessor Securities) is registered at the close of
business on a Special Record Date for the payment of such Defaulted Interest to
be fixed by the Trustee, notice of which shall be given to Holders of
Securities not less than 10 days prior to such Special Record Date, or be paid
at any time in any other lawful manner not inconsistent with the requirements
of any securities exchange on which the Securities may be listed, and upon such
notice as may be required by such exchange, all as more fully provided in said
Indenture.





                                       12
<PAGE>   19
         The Company shall have the right at any time during the term of this
Security, from time to time, to extend the interest payment period of such
Security for up to six consecutive quarters (an "Extension Period"), during
which periods interest will compound quarterly and the Company shall have the
right to make partial payments of interest on any Interest Payment Date, and at
the end of which Extension Period the Company shall pay all interest then
accrued and unpaid (together with Additional Interest thereon to the extent
that payment of such interest is permitted by applicable law).  Prior to the
termination of any such Extension Period, the Company may further extend the
interest payment period, provided that such Extension Period together with all
such previous and further extensions thereof shall not exceed six consecutive
quarters or extend beyond the Maturity of this Security.  Upon the termination
of any such Extension Period and upon the payment of all accrued and unpaid
interest and any Additional Interest then due, the Company may select a new
Extension Period, subject to the foregoing requirements.  No interest shall be
due and payable during an Extension Period except at the end thereof.  The
Company shall give the Holder of this Security and the Trustee written notice
of its selection of an Extension Period at least one Business Day prior to the
earlier of (i) the Interest Payment Date or (ii) the date Enron Capital Trust I
is required to give notice to the New York Stock Exchange or other applicable
self-regulatory organization or to holders of the Trust Preferred Securities of
the record date or the date such distributions are payable, but in any event
not less than one Business Day prior to such record date.

         Payment of the principal of and interest on this Security will be made
at the office or agency of the Company maintained for that purpose in New York,
New York, in such coin or currency of the United States of America as at the
time of payment is legal tender for payment of public and private debts;
provided, however, that at the option of the Company payment of interest may be
made (i) by check mailed to the address of the Person entitled thereto as such
address shall appear in the Security Register or (ii) by wire transfer in
immediately available funds at such place and to such account as may be
designated by the Person entitled thereto as specified in the Security
Register.

         The indebtedness evidenced by this Security is, to the extent provided
in the Indenture, subordinate and subject in right of payment to the prior
payment in full of all Senior Indebtedness, and this Security is issued subject
to the provisions of the Indenture with respect thereto.  Each Holder of this
Security, by accepting the same, (a) agrees to and shall be bound by such
provisions, (b) authorizes and directs the Trustee on his behalf to take such
action as may be necessary or appropriate to effectuate the subordination so
provided and (c) appoints the Trustee his attorney-in-fact for any and all such
purposes.  Each Holder hereof, by his acceptance hereof, waives all notice of
the acceptance of the subordination provisions contained herein and in the
Indenture of each holder of Senior Indebtedness, whether now outstanding or
hereafter incurred, and waives reliance by each such holder upon said
provisions.

         Reference is hereby made to the further provisions of the Indenture
summarized on the reverse hereof, which further provisions shall for all
purposes have the same effect as if set forth herein.

         Unless the certificate of authentication hereon has been executed by
the Trustee referred to on the reverse hereof by manual signature, this
Security shall not be entitled to any benefit under the Indenture or be valid
or obligatory for any purpose.





                                       13
<PAGE>   20
         IN WITNESS WHEREOF, Enron Corp. has caused this instrument to be duly
executed under its corporate seal.

Dated: ________, 1996

                                        ENRON CORP.
                                        
                                        
                                        By:
                                            -----------------------------------
                                            Name:
                                            Title:

SECTION 203.  Form of Reverse of Security.

         This Security is one of a duly authorized issue of Securities of the
Company, designated as its 7.75% Subordinated Debentures Due 2016 (herein
called the "Securities"), limited in aggregate principal amount to $181,926,000
issued under an Indenture, dated as of November 21,1996 (herein called the
"Indenture"), between the Company and The Chase Manhattan Bank, as Trustee
(herein called the "Trustee," which term includes any successor trustee under
the Indenture), to which Indenture and all indentures supplemental thereto
reference is hereby made for a statement of the respective rights, limitations
of rights, duties and immunities thereunder of the Trustee, the Company and the
Holders of the Securities, and of the terms upon which the Securities are, and
are to be, authenticated and delivered.

         All terms used in this Security which are defined in the Indenture
shall have the meanings assigned to them in the Indenture.

         At any time on or after December 31, 2001, the Company shall have the
right, subject to the terms and conditions of Article Twelve of the Indenture,
to redeem this Security at the option of the Company, without premium or
penalty, in whole or in part, at a Redemption Price equal to 100% of the
principal amount to be redeemed plus accrued but unpaid interest, including any
Additional Interest, if any, to the Redemption Date.  If a Partnership Special
Event shall occur and be continuing, the Company shall have the right, subject
to the terms and conditions of Article Twelve of the Indenture, to redeem this
Security, without premium or penalty, in whole but not in part, at a Redemption
Price equal to 100% of the principal amount thereof plus accrued but unpaid
interest, including any Additional Interest, if any, to the Redemption Date.
Any redemption pursuant to this paragraph will be made upon not less than 30
nor more than 60 days' notice, at the Redemption Price.  If the Securities are
only partially redeemed by the Company, the Securities will be redeemed pro
rata, by lot or in such other manner as the Trustee shall deem appropriate and
fair in its discretion and that may provide for the selection of a portion or
portions (equal to twenty-five U.S. dollars ($25) or any integral multiple
thereof) of the principal amount of any Security.

         In the event of redemption of this Security in part only, a new
Security or Securities for the unredeemed portion hereof will be issued in the
name of the Holder hereof upon the cancellation hereof.





                                       14
<PAGE>   21
         If an Event of Default with respect to the Securities shall occur and
be continuing, the principal of the Securities may be declared due and payable
in the manner, with the effect and subject to the conditions provided in the
Indenture.

         The Indenture contains provisions for satisfaction and discharge at
any time of the entire indebtedness of this Security upon compliance by the
Company with certain conditions set forth in the Indenture.

         The Indenture contains provisions permitting the Company and the
Trustee, with the consent of Holders of not less than a majority in principal
amount of the Outstanding Securities, to modify the Indenture in a manner
affecting the rights of the Holders of the Securities; provided that no such
modification may, without the consent of the Holder of each Outstanding
Security, (i) extend the fixed maturity of the Securities, or reduce the
principal amount thereof, or reduce the rate or extend the time of payment of
interest thereon, or reduce any premium payable upon the redemption thereof, or
(ii) reduce the percentage of principal amount of the Securities, the Holders
of which are required to consent to any such modification of the Indenture.
The Indenture also contains provisions permitting Holders of specified
percentages in principal amount of the Securities at the time Outstanding, on
behalf of the Holders of all Securities, to waive compliance by the Company
with certain provisions of the Indenture and certain past defaults under the
Indenture and their consequences.  Any such consent or waiver by the Holder of
this Security shall be conclusive and binding upon such Holder and upon all
future Holders of this Security and of any Security issued upon the
registration of transfer hereof or in exchange herefor or in lieu hereof,
whether or not notation of such consent or waiver is made upon this Security.

         No reference herein to the Indenture and no provision of this Security
or of the Indenture shall alter or impair the obligation of the Company, which
is absolute and unconditional, to pay the principal of and interest on this
Security at the times, place and rate, and in the coin or currency, herein
prescribed.

         As provided in the Indenture and subject to certain limitations
therein set forth, the transfer of this Security is registrable in the Security
Register, upon surrender of this Security for registration of transfer at the
office or agency of the Company in New York, New York, duly endorsed by, or
accompanied by a written instrument of transfer in form satisfactory to the
Company and the Security Registrar duly executed by, the Holder hereof or his
attorney duly authorized in writing, and thereupon one or more new Securities,
of authorized denominations and for the same aggregate principal amount, will
be issued to the designated transferee or transferees.  No service charge shall
be made for any such registration of transfer or exchange, but the Company may
require payment of a sum sufficient to cover any tax or other governmental
charge payable in connection therewith.

         Prior to due presentment of this security for registration of
transfer, the Company, the Trustee and any of their respective agents may treat
the Person in whose name this Security is registered as the owner hereof for
all purposes, whether or not this Security shall be overdue, and neither the
Company, the Trustee nor any such agent shall be affected by notice to the
contrary.





                                       15
<PAGE>   22
         The Securities are issuable only in registered form without coupons in
denominations of $25 and any integral multiple thereof.  As provided in the
Indenture and subject to certain limitations therein set forth, Securities are
exchangeable for a like aggregate principal amount of Securities of a different
authorized denomination, as requested by the Holder surrendering the same.

         THIS INDENTURE AND THE SECURITIES SHALL BE GOVERNED BY AND CONSTRUED
IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO
CONFLICTS OF LAWS PRINCIPLES THEREOF.

SECTION 204.  Form of Trustee's Certificate of Authentication.

         This is one of the Securities referred to in the within-mentioned
Indenture.

                                        [NAME OF TRUSTEE], as Trustee
                                        
                                        
                                        By:
                                            -----------------------------------
                                                    Authorized Signatory

                                 ARTICLE THREE

                                 The Securities

SECTION 301.  Title and Terms.

         The aggregate principal amount of Securities which may be
authenticated and delivered under this Indenture is limited to $181,926,000,
except for Securities authenticated and delivered upon registration of transfer
of, or in exchange for, or in lieu of, other securities pursuant to Section
303, 304, 305, 306 or 1208.

         The Securities shall be known and designated as the "7.75%
Subordinated Debentures Due 2016" of the Company.  Their Stated Maturity shall
be September 30, 2016, and they shall bear interest at the rate of 7.75% per
annum, from November 21, 1996 or from the most recent Interest Payment Date to
which interest has been paid or duly provided for, as the case may be, payable
quarterly (subject to deferral as set forth herein), in arrears, on March 31,
June 30, September 30 and December 31 of each year, commencing December 31,
1996 until the principal thereof is paid or made available for payment.
Interest will compound quarterly and will accrue at the rate of 7.75% per annum
on any interest installment in arrears for more than one quarter or during an
extension of an interest payment period as set forth below in this Section 301.
In the event that any date on which interest is payable on the Securities is
not a Business Day, then a payment of the interest payable on such date will be
made on the next succeeding day which is a Business Day (except that, if such
Business Day is in the next succeeding calendar year, such Interest Payment
Date shall be the immediately preceding Business Day) (and without any interest
or other payment in respect of any such delay).





                                       16
<PAGE>   23
         The Company shall have the right, at any time during the term of the
Securities, from time to time to extend the interest payment period for up to
six consecutive quarters (the "Extension Period") during which period interest
will compound quarterly and the Company shall have the right to make partial
payments of interest on any Interest Payment Date, and at the end of which
Extension Period the Company shall pay all interest then accrued and unpaid
thereon (together with Additional Interest at the rate specified for the
Securities to the extent permitted by applicable law).  Prior to the
termination of any such Extension Period, the Company may further extend the
interest payment period, provided that such Extension Period together with all
such previous and further extensions thereof shall not exceed six consecutive
quarters or extend beyond the Maturity of the Securities.  Upon the termination
of any Extension Period and upon the payment of all accrued and unpaid interest
and any Additional Interest then due, the Company may select a new Extension
Period, subject to the foregoing requirements.  No interest shall be due and
payable during an Extension Period, except at the end thereof.  The Company
shall give the Trust, the Partnership and the Trustee notice of its selection
of such Extension Period subject to the above requirements at least one
Business Day prior to the earlier of (i) the Interest Payment Date or (ii) the
date the Trust is required to give notice to the New York Stock Exchange or
other applicable self-regulatory organization or to holders of the Trust
Preferred Securities of the record date or the date such distributions are
payable, but in any event not less than one Business Day prior to such record
date.

         The principal of and interest on the Securities shall be payable at
the office or agency of the Company in the United States maintained for such
purpose and at any other office or agency maintained by the Company for such
purpose in such coin or currency of the United States of America as at the time
of payment is legal tender for payment of public and private debts; provided,
however, that at the option of the Company payment of interest may be made (i)
by check mailed to the address of the Person entitled thereto as such address
shall appear in the Security Register or (ii) by wire transfer in immediately
available funds at such place and to such account as may be designated by the
Person entitled thereto as specified in the Security Register.

         The Securities shall be subordinated in right of payment to Senior
Indebtedness as provided in Article Eleven.

         The Securities shall be redeemable as provided in Article Twelve.

SECTION 302.  Denominations.

         The Securities shall be issuable only in registered form, without
coupons, and only in denominations of $25 and any integral multiple thereof.

SECTION 303.  Execution, Authentication, Delivery and Dating.

         The Securities shall be executed on behalf of the Company by its
Chairman, one of its Vice Chairman, its President or one of its Vice
Presidents.  The signature of any of these officers on the securities may be
manual or facsimile.





                                       17
<PAGE>   24
         Securities bearing the manual or facsimile signatures of individuals
who were at any time the proper officers of the Company shall bind the Company,
notwithstanding that such individuals or any of them have ceased to hold such
offices prior to the authentication and delivery of such Securities or did not
hold such offices at the date of such Securities.

         At any time and from time to time after the execution and delivery of
this Indenture, the Company may deliver Securities executed by the Company to
the Trustee for authentication, together with a Company Order for the
authentication and delivery of such Securities; and the Trustee in accordance
with such Company Order shall authenticate and deliver such Securities as in
this Indenture provided and not otherwise.

         Each Security shall be dated the date of its authentication.

         No Security shall be entitled to any benefit under this Indenture or
be valid or obligatory for any purpose unless there appears on such Security a
certificate of authentication substantially in the form provided for herein
executed by the Trustee by manual signature and such certificate upon any
Security shall be conclusive evidence, and the only evidence, that such
Security has been duly authenticated and delivered hereunder.

SECTION 304.  Temporary Securities.

         Pending the preparation of definitive Securities, the Company may
execute, and upon Company Order the Trustee shall authenticate and deliver,
temporary Securities which are printed, lithographed, typewritten, mimeographed
or otherwise produced, in any authorized denomination, substantially of the
tenor of the definitive Securities in lieu of which they are issued and with
such appropriate insertions, omissions, substitutions and other variations as
the officers executing such Securities may determine, as evidenced by their
execution of such Securities.

         If temporary Securities are issued, the Company will cause definitive
Securities to be prepared without unreasonable delay.  After the preparation of
definitive Securities, the temporary Securities shall be exchangeable for
definitive Securities upon surrender of the temporary Securities at any office
or agency of the Company designated pursuant to Section 1002, without charge to
the Holder.  Upon surrender for cancellation of any one or more temporary
Securities the Company shall execute and the Trustee shall authenticate and
deliver in exchange therefor a like principal amount of definitive Securities
of authorized denominations.  Until so exchanged the temporary Securities shall
in all respects be entitled to the same benefits under this Indenture as
definitive Securities.

SECTION 305.  Registration, Registration of Transfer and Exchange.

         The Company shall cause to be kept at the Corporate Trust Office of
the Trustee a register (the register maintained in such office and in any other
office or agency designated pursuant Section 1002 being herein sometimes
collectively referred to as the "Security Register") in which, subject to such
reasonable regulations as it may prescribe, the Company shall provide for the
registration of Securities and of transfers of Securities.  The Trustee is
hereby appointed "Security Registrar" for the purpose of registering Securities
and transfers of Securities as herein provided.





                                       18
<PAGE>   25
         Upon surrender for registration of transfer of any Security at an
office or agency of the Company designated pursuant to Section 1002 for such
purpose, the Company shall execute, and the Trustee shall authenticate and
deliver, in the name of the designated transferee or transferees, one or more
new Securities of any authorized denominations and of a like aggregate
principal amount.

         At the option of the Holder, Securities may be exchanged for other
Securities of any authorized denominations and of a like aggregate principal
amount, upon surrender of the Securities to be exchanged at such office or
agency.  Whenever any Securities are so surrendered for exchange, the Company
shall execute, and the Trustee shall authenticate and deliver, the Securities
which the Holder making the exchange is entitled to receive.

         All Securities issued upon any registration of transfer or excess of
Securities shall be the valid obligations of the Company, evidencing the same
debt, and entitled to the same benefits under this Indenture, as the Securities
surrendered upon such registration of transfer or exchange.

         Every Security presented or surrendered for registration of transfer
or for exchange shall (if so required by the Company or the Trustee) be duly
endorsed, or be accompanied by a written instrument of transfer in form
satisfactory to the Company and the Security Registrar duly executed, by the
Holder thereof or his attorney duly authorized in writing.

         No service charge shall be made for any registration of transfer or
exchange of Securities, but the Company may require payment of a sum sufficient
to cover any tax or other governmental charge that may be imposed in connection
with any registration of transfer or exchange of Securities, other than
exchanges pursuant to Section 304 or 1208 not involving any transfer.

         If the Securities are to be redeemed in part, the Company will not be
required to issue, register the transfer of or exchange any Securities during a
period beginning at the opening of business 15 days before the day of mailing
of a notice of redemption of any such Securities that may be selected for
redemption and ending at the close of business on the day of such mailing,
except the unredeemed portion of any such Securities being redeemed in part.

SECTION 306.  Mutilated, Destroyed, Lost and Stolen Securities.

         If any mutilated Security is surrendered to the Trustee, the Company
shall execute and the Trustee shall authenticate and deliver in exchange
therefor a new Security of like tenor and principal amount and bearing a number
not contemporaneously outstanding.

         If there shall be delivered to the Company and the Trustee (i)
evidence to their satisfaction of the destruction, loss or theft of any
security and (ii) such security or indemnity as may be required by them to save
each of them and any of the officers, directors, employees or agents of either
of them harmless, then, in the absence of notice to the Company or the Trustee
that such Security has been acquired by a bona fide purchaser, the Company
shall execute and the Trustee shall authenticate and deliver, in lieu of any
such destroyed, lost or stolen Security, a new Security of like tenor and
principal amount and bearing a number not contemporaneously outstanding.





                                       19
<PAGE>   26
         In case any such mutilated, destroyed, lost or stolen Security has
become or is about to become due and payable, the Company in its discretion
may, instead of issuing a new Security, pay such Security.

         Upon the issuance of any new Security under this Section, the Company
may require the payment of a sum sufficient to cover any tax or other
governmental charge that may be imposed in relation thereto and any other
expenses (including the fees and expenses of the Trustee) connected therewith.

         Every new Security issued pursuant to this Section in lieu of any
destroyed, lost or stolen Security shall constitute an original additional
contractual obligation of the Company, whether or not the destroyed, lost or
stolen Security shall be at any time enforceable by anyone, and shall be
entitled to all the benefits of this Indenture equally and proportionately with
any and all other Securities duly issued hereunder.

         The provisions of this Section are exclusive and shall preclude (to
the extent lawful) all other rights and remedies with respect to the
replacement or payment of mutilated, destroyed, lost or stolen Securities.

SECTION 307.  Payment of Interest; Interest Rights Preserved.

         Interest on any Security which is payable, and is punctually paid or
duly provided for, on any Interest Payment Date shall be paid to the Person in
whose name that Security (or one or more Predecessor Securities) is registered
at the close of business on the Regular Record Date for such interest.

         Any interest on any Security which is payable, but is not punctually
paid or duly provided for, on any Interest Payment Date (herein called
"Defaulted Interest") shall forthwith cease to be payable to the Holder on the
relevant Regular Record Date by virtue of having been such Holder, and such
Defaulted Interest may be paid by the Company, at its election in each case, as
provided in Clause (1) or (2) below:

         (1) the Company may elect to make payment of any Defaulted Interest to
the Persons in whose names the Securities (or their respective Predecessor
Securities) are registered at the close of business on a Special Record Date
for the payment of such Defaulted Interest, which shall be fixed in the
following manner.  The Company shall notify the Trustee in writing of the
amount of Defaulted Interest proposed to be paid on each Security and the date
of the proposed payment, and at the same time the Company shall deposit with
the Trustee an amount of money equal to the aggregate amount proposed to be
paid in respect of such Defaulted Interest or shall make arrangements
satisfactory to the Trustee for such deposit prior to the date of the proposed
payment, such money when deposited to be held in trust for the benefit of the
Persons entitled to such Defaulted Interest as in this Clause provided.
Thereupon the Trustee shall fix a Special Record Date for the payment of such
Defaulted Interest which shall be not more than 15 days and not less than 10
days prior to the date of the proposed payment and not less than 10 days after
the receipt by the Trustee of the notice of the proposed payment.  The Trustee
shall promptly notify the Company of





                                       20
<PAGE>   27
such Special Record Date and, in the name and at the expense of the Company,
shall cause notice of the proposed payment of such Defaulted Interest and the
Special Record Date therefor to be mailed, first-class postage prepaid, to each
Holder at his address as it appears in the Security Register, not less than 10
days prior to such Special Record Date.  Notice of the proposed payment of such
Defaulted Interest and the Special Record Date therefor having been so mailed,
such Defaulted Interest shall be paid to the Persons in whose names the
Securities (or their respective Predecessor Securities) are registered at the
close of business on such Special Record Date and shall no longer be payable
pursuant to the following clause (2).

         (2) The Company may make payment of any Defaulted Interest in any
other lawful manner not inconsistent with the requirements of any securities
exchange on which the Securities may be listed, and, if so listed, upon such
notice as may be required by such exchange, if, after notice given by the
Company to the Trustee of the proposed payment pursuant to this clause, such
manner of payment shall be deemed practicable by the Trustee.

         Subject to the foregoing provisions of this Section, each Security
delivered under this Indenture upon registration of transfer of or in exchange
for or in lieu of any other Security shall carry the rights to interest accrued
and unpaid, and to accrue (including in each such case Additional Interest),
which were carried by such other Security.

SECTION 308.  Persons Deemed Owners.

         Prior to due presentment of a Security for registration of transfer,
the Company, the Trustee and any agent of any of them shall treat the Person in
whose name such Security is registered as the owner of such Security for the
purpose of receiving payment of principal of and (subject to Section 307)
interest (including Additional Interest) on such Security and for all other
purposes whatsoever, whether or not such Security be overdue, and neither the
Company, the Trustee nor any agent of them shall be affected by notice to the
contrary.

SECTION 309.  Cancellation.

         All Securities surrendered for payment, redemption, registration of
transfer or exchange shall, if surrendered to any Person other than the
Trustee, be delivered to the Trustee and shall be promptly cancelled by it.
The Company may at any time deliver to the Trustee for cancellation any
Securities previously authenticated and delivered hereunder which the Company
may have acquired in any manner whatsoever, and all Securities so delivered
shall be promptly cancelled by the Trustee.  No Securities shall be
authenticated in lieu of or in exchange for any Securities cancelled as
provided in this Section, except as expressly permitted by this Indenture.  All
cancelled Securities held by the Trustee shall be disposed of as directed by a
Company Order.

SECTION 310.  Computation of Interest.

         Interest on the Securities shall be computed on the basis of a 360-day
year of twelve 30-day months.





                                       21
<PAGE>   28
                                  ARTICLE FOUR

                           Satisfaction and Discharge

SECTION 401.  Satisfaction and Discharge of Indenture.

         This Indenture shall cease to be of further effect (except as to any
surviving rights of registration of transfer or exchange of Securities herein
expressly provided for and any amounts owed to the Trustee hereunder), and the
Trustee, on demand of and at the expense of the Company, shall execute proper
instruments acknowledging satisfaction and discharge of this Indenture, when

         (1)  either

                 (A) all Securities theretofore authenticated and delivered
         (other than (i) Securities which have been destroyed, lost or stolen
         and which have been replaced or paid as provided in Section 306 and
         (ii) Securities for whose payment money has theretofore been deposited
         in trust or segregated and held in trust by the Company and thereafter
         repaid to the Company or discharged from such trust, as provided in
         Section 1003) have been delivered to the Trustee for cancellation; or

                 (B)  all such Securities not theretofore delivered to the
         Trustee for cancellation

                          (i) have become due and payable,

                          (ii) will become due and payable at their Stated
                 Maturity within one year, or

                          (iii) are to be called for redemption within one year
                 under arrangements satisfactory to the Trustee for the giving
                 of notice of redemption by the Trustee in the name, and at the
                 expense, of the Company

         and the Company, in the case of (i), (ii) or (iii) above, has
         deposited or caused to be deposited with the Trustee as trust funds in
         trust for the purpose and amount sufficient to pay and discharge the
         entire indebtedness on such Securities not theretofore delivered to
         the Trustee for cancellation, for principal and interest (including
         Additional Interest) to the date of such deposit (in the case of
         Securities which have become due and payable) or to the Stated
         Maturity or Redemption Date, as the case may be;

         (2)  the Company has paid or caused to be paid all other sums payable
hereunder by the Company; and

         (3) the Company has delivered to the Trustee an Officers' Certificate
and an Opinion of Counsel, each stating that all conditions precedent herein
provided for relating to the satisfaction and discharge of this Indenture have
been complied with.  Notwithstanding the satisfaction and discharge of this
Indenture, the obligations of the Company to the Trustee under Section 607 and,
if money shall have been deposited with the Trustee pursuant to subclause (B)
of Clause (1) of this Section,





                                       22
<PAGE>   29
the obligations of the Trustee under Section 402 and the last paragraph of
Section 1003 shall survive.  SECTION 402.  Application of Trust Money.

         Subject to the provisions of the last paragraph of Section 1003, all
money deposited with the Trustee pursuant to Section 401 shall be held in trust
and applied by it, in accordance with the provisions of the Securities and this
Indenture, to the payment, either directly or through any Paying Agent
(including the Company acting as its own Paying Agent) as the Trustee may
determine, to the Persons entitled thereto, of the principal and interest for
whose payment such money has been deposited with the Trustee.  The Trustee
shall not invest money deposited with it pending distribution of such amounts.

                                  ARTICLE FIVE

                                    Remedies

SECTION 501.  Events of Default.

         "Event of Default," wherever used herein, means any one of the
following events that has occurred and is continuing (whatever the reason for
such Event of Default and whether it shall be voluntary or involuntary or be
effected by operation of law or pursuant to any judgment, decree or order of
any court or any order, rule or regulation of any administrative or
governmental body):

         (1) failure for 90 days to pay any interest on the Securities,
including any Additional Interest in respect thereof, when due (subject to the
deferral of any due date in the case of an Extension Period); or

         (2) failure to pay any principal on the Securities when due whether at
Stated Maturity, upon redemption or otherwise; or

         (3) failure to observe or perform in any material respect any other
covenant herein for 90 days after written notice of such failure (specified as
a "Notice of Default"), requiring the Company to remedy the same shall have
been given to the Company by the Trustee or the holders of at least 25% in
principal amount of the Outstanding Securities; or


         (4) a court or governmental agency having jurisdiction shall enter a
decree or order for relief in respect of the Company in an involuntary case
under any applicable federal or state bankruptcy, insolvency or other similar
law now or hereafter in effect, or appointing a receiver, liquidator, assignee,
custodian, trustee, sequestrator (or similar official) of the Company or for
all or substantially all of its property or ordering the winding up or
liquidation of its affairs, and such decree or order shall remain unstayed and
in effect for a period of 90 consecutive days; or

         (5) the Company shall commence a voluntary case under any applicable
bankruptcy, insolvency or other similar law now or hereafter in effect, or
consent to the entry of an order for relief in an involuntary case under any
such law, or consent to the appointment or taking possession





                                       23
<PAGE>   30
by a receiver, liquidator, assignee, custodian, trustee, sequestrator (or
similar official) of the Company or for all or substantially all of its
property or make any general assignment for the benefit of creditors; or the
Company shall admit in writing its inability to pay its debts generally as they
become due.

SECTION 502.  Acceleration of Maturity; Rescission and Annulment.

         If an Event of Default occurs and is continuing, then and in every
such case the Trustee or the Holders of not less than 25% in aggregate
principal amount of the Outstanding Securities shall have the right to declare
the principal of and the interest on all the Securities (including any
Additional Interest) and any other amounts payable hereunder to be due and
payable immediately, by a notice in writing to the Company (and to the Trustee
if given by Holders) and to enforce any and all other rights of Holders of
Securities as creditors with respect to the Securities.  Upon any such
declaration such principal and all accrued interest shall become immediately
due and payable.

         At any time after such a declaration of acceleration has been made and
before a judgment or decree for payment of the money due has been obtained by
the Trustee as hereinafter provided in this Article, the Holders of a majority
in principal amount of the Outstanding Securities, by written notice to the
Company and the Trustee, may rescind and annul such declaration and its
consequences if:

         (1) the Company has paid or deposited with the Trustee a sum
sufficient to pay,

                 (A) all overdue interest (including any Additional Interest)
         on all Securities,

                 (B) the principal of any Securities which have became due
         otherwise than by such declaration of acceleration and interest
         thereon at the rate borne by the Securities, and

                 (C) all sums paid or advanced by the Trustee hereunder and the
         reasonable compensation, expenses, disbursements and advances of the
         Trustee, its agents and counsel;  and

         (2) all Events of Default, other than the non-payment of the principal
of Securities which have become due solely by such declaration of acceleration,
have been cured or waived as provided in Section 513.

         No such rescission shall affect any subsequent default or impair any
right consequent thereon.

SECTION 503.  Collection of Indebtedness and Suits for Enforcement by Trustee.

         The Company covenants that if

         (1) default is made in the payment of any interest (including any
Additional Interest) on any Security when such interest becomes due and payable
and such default continues for a period of 90 days (subject to the deferral of
any due and payable interest in the case of an Extension Period), or





                                       24
<PAGE>   31
         (2) default is made in the payment of the principal of any Security at
the Maturity thereof, the Company will, upon demand of the Trustee, pay to it,
for the benefit of the Holders of such Securities, the whole amount then due
and payable on such Securities for principal and interest (including any
Additional Interest), at the rate borne by the Securities, and, in addition
thereto, such further amount as shall be sufficient to cover the costs and
expenses of collection, including the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel.

         If an Event of Default occurs and is continuing, the Trustee may in
its discretion proceed to protect and enforce its rights and the rights of the
Holders by such appropriate judicial proceedings as the Trustee shall deem most
effective to protect and enforce any such rights, whether for the specific
enforcement of any covenant or agreement in this Indenture or in aid of the
exercise of any power granted herein, or to enforce any other proper remedy.

SECTION 504.  Trustee May File Proofs of Claim.

         In case of any judicial proceeding relative to the Company, its
property or its creditors, the Trustee shall be entitled and empowered, by
intervention in such proceeding or otherwise, to take any and all actions
authorized under the Trust Indenture Act in order to have claims of the Holders
and the Trustee allowed in any such proceeding.  In particular, the Trustee
shall be authorized to collect and receive any moneys or other property payable
or deliverable on any such claims and to distribute the same; and any
custodian, receiver, assignee, trustee, liquidator, sequestrator or other
similar official in any such judicial proceeding is hereby authorized by each
Holder to make such payments to the Trustee and, in the event that the Trustee
shall consent to the making of such payments directly to the holders, to pay to
the Trustee any amount due it for the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel, and any
other amounts due the Trustee under Section 607.

         No provision of this Indenture shall be deemed to authorize the
Trustee to authorize or consent to or accept or adopt on behalf of any Holder
any plan of reorganization, arrangement, adjustment or composition affecting
the Securities or the rights of any Holder thereof or to authorize the Trustee
to vote in respect of the claim of any Holder in any such proceeding.

SECTION 505.  Trustee May Enforce Claims Without Possession of Securities.

         All rights of action and claims under this Indenture or the Securities
may be prosecuted and enforced by the Trustee without the possession of any of
the Securities or the production thereof in any proceeding relating thereto,
and any such proceeding instituted by the Trustee shall be brought in its own
name as trustee of an express trust, and any recovery of judgment shall, after
provision for the payment of the reasonable compensation, expenses,
disbursements and advances of the Trustee, its agents and counsel, be for the
ratable benefit of the Holders of the Securities in respect of which such
judgment has been recovered.





                                       25
<PAGE>   32
SECTION 506.  Application of Money Collected.

         Subject to Article Eleven, any money collected by the Trustee pursuant
to this Article shall be applied in the following order, at the date or dates
fixed by the Trustee and, in case of the distribution of such money on account
of principal or interest (including any Additional Interest), upon presentation
of the Securities and the notation thereon of the payment if only partially
paid and upon surrender thereof if fully paid:

         FIRST: To the payment of all amounts due the Trustee under Section
607;

         SECOND: To the payment of the amounts then due and unpaid for
principal of and interest (including any Additional Interest) on the Securities
in respect of which or for the benefit of which such money has been collected,
ratably, without preference or priority of any kind, according to the amounts
due and payable on such Securities for principal and interest (including any
Additional Interest), respectively; and

         THIRD: The balance, if any, to the Company.

SECTION 507.  Limitation on Suits.

         No Holder of any Security shall have any right to institute any
proceeding, judicial or otherwise, with respect to this Indenture, or for the
appointment of a receiver or trustee, or for any other remedy hereunder, unless

         (1) such Holder has previously given written notice to the Trustee of
a continuing Event of Default;

         (2) the Holders of not less than 25% in principal amount of the
Outstanding Securities shall have made written request to the Trustee to
institute proceedings in respect of such Event of Default in its own name as
Trustee hereunder;

         (3) such Holder or Holders have offered to the Trustee such indemnity
as is satisfactory to it against the costs, expenses and liabilities to be
incurred in compliance with such request;

         (4) the Trustee for 60 days after its receipt of such notice, request
and offer of indemnity has failed to institute any such proceeding; and

         (5) no direction inconsistent with such written request has been given
to the Trustee during such 60-day period by the Holders of a majority in
principal amount of the Outstanding Securities; it being understood and
intended that no one or more Holders shall have any right in any manner
whatever by virtue of, or by availing of, any provision of this Indenture to
affect, disturb or prejudice the rights of any other Holders, or to obtain or
to seek to obtain priority or preference over any other Holders or to enforce
any right under this Indenture, except in the manner herein provided and for
the equal and ratable benefit of all the Holders.





                                       26
<PAGE>   33
SECTION 508.  Unconditional Right of Holders to Receive Principal and Interest.

         Notwithstanding any other provision in this Indenture, the Holder of
any Security shall have the right, which is absolute and unconditional, to
receive payment of the principal of and (subject to Section 307) interest
(including any Additional Interest) on such Security on the respective Stated
Maturities (subject to the deferral of any due date in the case of an Extension
Period) expressed in such Security (or, in the case of redemption, on the
Redemption Date) and to institute suit for the enforcement of any such payment,
and such rights shall not be impaired without the consent of such Holder.

SECTION 509.  Restoration of Rights and Remedies.

         If the Trustee or any Holder has instituted any proceeding to enforce
any right or remedy under this Indenture and such proceeding has been
discontinued or abandoned for any reason, or has been determined adversely to
the Trustee or to such Holder, then and in every such case, subject to any
determination in such proceeding, the Company, the Trustee and the Holders
shall be restored severally and respectively to their former positions
hereunder and thereafter all rights and remedies of the Trustee and the Holders
shall continue as though no such proceeding had been instituted.

SECTION 510.  Rights and Remedies Cumulative.

         Except as otherwise provided with respect to the replacement or
payment of mutilated, destroyed, lost or stolen Securities in the last
paragraph of Section 306, no right or remedy herein conferred upon or reserved
to the Trustee or to the Holders is intended to be exclusive of any other right
or remedy, and every right and remedy shall, to the extent permitted by law, be
cumulative and in addition to every other right and remedy given hereunder or
now or hereafter existing at law or in equity or otherwise.  The assertion or
employment of any right or remedy hereunder, or otherwise, shall not prevent
the concurrent assertion or employment of any other appropriate right or
remedy.

SECTION 511.  Delay or Omission Not Waiver.

         No delay or omission of the Trustee or of any Holder of any Security
to exercise any right or remedy accruing upon any Event of Default shall impair
any such right or remedy or constitute a waiver of any such Event of Default or
an acquiescence therein.  Every right and remedy given by this Article or by
law to the Trustee or to the Holders may be exercised from time to time, and as
often as may be deemed expedient, by the Trustee or by the Holders, as the case
may be.

SECTION 512.  Control by Holders.

         The Holders of a majority in principal amount of the Outstanding
Securities shall have the right to direct the time, method and place of
conducting any proceeding for any remedy available to the Trustee or exercising
any trust or power conferred on the Trustee, provided that

         (1) such direction shall not be in conflict with any rule of law or
with this Indenture; and





                                       27
<PAGE>   34
         (2) the Trustee may take any other action deemed proper by the Trustee
which is not inconsistent with such direction.

SECTION 513.  Waiver of Past Defaults.

         Subject to Section 902, the Holders of not less than a majority in
principal amount of the Outstanding Securities may on behalf of the Holders of
all the Securities waive any past default hereunder and its consequences,
except a default

         (1) in the payment of the principal of or interest (including any
Additional Interest) on any Security (unless such default has been cured and a
sum sufficient to pay all matured installments of interest and principal due
otherwise than by acceleration have been deposited with the Trustee); or

         (2) in respect of a covenant or provision hereof which under Article
Nine cannot be modified or amended without the consent of the Holder of each
Outstanding Security affected.

         Upon any such waiver, such default shall cease to exist, and any Event
of Default arising therefrom shall be deemed to have been cured, for every
purpose of this Indenture; but no such waiver shall extend to any subsequent or
other default or impair any right consequent thereon.

SECTION 514.  Undertaking for Costs.

         In any suit for the enforcement of any right or remedy under this
Indenture, or in any suit against the Trustee for any action taken, suffered or
omitted by it as Trustee, a court may require any party litigant in such court
to file an undertaking to pay the costs of such suit, and may assess costs
against any such party litigant, in the manner and to the extent provided in
the Trust Indenture Act; provided, that neither this Section nor the Trust
Indenture Act shall be deemed to authorize any court to require such an
undertaking or to make such an assessment in any suit instituted by the Company
or the Trustee or in any suit for the enforcement of the right to receive the
principal of and interest (including any Additional Interest) on any Security.

SECTION 515.  Acknowledgment.

         The Company acknowledges that so long as the Partnership is a Holder,
a holder of record of Preferred Securities may to the fullest extent permitted
by law on behalf of the Partnership, when and as provided in the Limited
Partnership Agreement, directly institute a legal proceeding against the
Company under this Indenture, without first instituting any legal proceeding
against the Property Trustee  (as such term is defined in the Limited
Partnership Agreement) or any other party.





                                       28
<PAGE>   35
                                  ARTICLE SIX

                                  The Trustee

SECTION 601.  Certain Duties and Responsibilities.

         The duties and responsibilities of the Trustee shall be as provided by
the Trust Indenture Act.  Notwithstanding the foregoing, no provision of this
Indenture shall require the Trustee to expend or risk its own funds or
otherwise incur any financial liability in the performance of any of its duties
hereunder, or in the exercise of any of its rights or powers, if it shall have
reasonable grounds for believing that repayment of such funds or adequate
indemnity against such risk or liability is not reasonably assured to it.
Whether or not therein expressly so provided, every provision of this Indenture
relating to the conduct or affecting the liability of or affording protection
to the Trustee shall be subject to the provisions of this Section.

SECTION 602.  Notice of Defaults.

         The Trustee shall give the Holders notice of any default  hereunder
actually known to a Responsible Officer of the Trustee as and to the extent
provided by the Trust Indenture Act; provided, however, that in the case of any
default of the character specified in Section 501(3), no such notice to Holders
shall be given until at least 30 days after the occurrence thereof.  For the
purpose of this Section, the term "default" means any event which is, or after
notice or lapse of time or both would become, an Event of Default.

SECTION 603.  Certain Rights of Trustee.

         Subject to the provisions of Section 601:

         (a) the Trustee may conclusively rely and shall be fully protected in
acting or refraining from acting upon any resolution, certificate, statement,
instrument, opinion, report, notice, request, direction, consent, order, bond,
debenture, note, other evidence of indebtedness or other paper or document
believed by it to be genuine and to have been signed or presented by the proper
party or parties;

         (b) any request or direction of the Company mentioned herein shall be
sufficiently evidenced by a Company Request or Company Order and any resolution
of the Board of Directors may be sufficiently evidenced by a Board Resolution;

         (c) whenever in the administration of this Indenture the Trustee shall
deem it desirable that a matter be proved or established prior to taking,
suffering or omitting any action hereunder, the Trustee (unless other evidence
be herein specifically prescribed) may, in the absence of bad faith on its
part, conclusively rely upon an Officers' Certificate;

         (d) the Trustee may, at the Company's expense, consult with counsel of
its choice, and the advice of such counsel or any Opinion of Counsel shall be
full and complete authorization and





                                       29
<PAGE>   36
protection in respect of any action taken, suffered or omitted by it hereunder
in good faith and in reliance thereon;

         (e) the Trustee shall be under no obligation to exercise any of the
rights or powers vested in it by this Indenture at the request or direction of
any of the Holders pursuant to this Indenture, unless such Holders shall have
offered to the Trustee security or indemnity satisfactory to it against the
costs, expenses and liabilities which might be incurred by it in compliance
with such request or direction;

         (f) the Trustee shall not be bound to make any investigation into the
facts or matters stated in any resolution, certificate, statement, instrument,
opinion, report, notice, request, direction, consent, order, bond, debenture,
note, other evidence of indebtedness or other paper or document, but the
Trustee, in its discretion, may make such further inquiry or investigation into
such facts or matters as it may see fit, and, if the Trustee shall determine to
make such further inquiry or investigation, it shall be entitled to examine the
books, records and premises of the Company, personally or by agent or attorney;

         (g) the Trustee may execute any of the trusts or powers hereunder or
perform any duties hereunder either directly or by or through agents or
attorneys and the Trustee shall not be responsible for any misconduct or
negligence on the part of any agent or attorney appointed with due care by it
hereunder;

         (h) the Trustee shall not be liable for any action taken, suffered, or
omitted to be taken by it in good faith and reasonably believed by it to be
authorized or within the discretion or rights or powers conferred upon it by
this Indenture;

         (i)  no provision of this Indenture shall require the Trustee to
expend or risk its own funds or otherwise incur financial liability in the
performance of any of its duties hereunder or in the exercise of any of its
rights or powers, if it shall have reasonable grounds to believe that
repayments of such funds or indemnity satisfactory to it against any loss,
liability or expense is not reasonably assured to it;

         (j)  the Trustee shall have no duty to monitor the performance of the
Company or its compliance with the covenants contained herein, nor shall it
have any liability in connection with the malfeasance or nonfeasance by the
Company; and

         (k)   any Paying Agent, Authenticating Agent or Security Registrar
appointed hereunder shall be entitled to all the rights, protections,
immunities and indemnities afforded to the Trustee hereunder.

SECTION 604.  Not Responsible for Recitals or Issuance of Securities.

         The recitals contained herein and in the Securities, except the
Trustee's certificates of authentication, shall be taken as the statements of
the Company, and the Trustee assumes no responsibility for their correctness.
The Trustee makes no representations as to the validity or





                                       30
<PAGE>   37
sufficiency of this Indenture or of the Securities.  The Trustee shall not be
accountable for the use or application by the Company of Securities or the
proceeds thereof.

SECTION 605.  May Hold Securities.

         The Trustee, any Paying Agent, any Security Registrar, or any other
agent of the Company, in its individual or any other capacity, may become the
owner or pledgee of Securities and, subject to Sections 608 and 613, may
otherwise deal with the Company with the same rights it would have if it were
not Trustee, Paying Agent, Security Registrar, or such other agent.  Money held
by the Trustee in trust hereunder shall not be invested by the Trustee pending
distribution thereof to the holders of the Securities.

SECTION 606.  Money Held in Trust.

         Money held by the Trustee in trust hereunder need not be segregated
from other funds except to the extent required by law.  The Trustee shall be
under no liability for interest on any money received by it hereunder except as
otherwise agreed in writing with the Company.

SECTION 607.  Compensation and Reimbursement.

         The Company agrees

         (1) to pay to the Trustee from time to time such reasonable
compensation as the Company and the Trustee shall from time to time agree in
writing for all services rendered by it hereunder (which compensation shall not
be limited by any provision of law in regard to the compensation of a trustee
of an express trust);

         (2) except as otherwise expressly provided herein, to reimburse the
Trustee upon its request for all reasonable fees, charges, expenses,
disbursements and advances incurred or made by the Trustee in accordance with
any provision of this Indenture or arising out of or in connection with the
acceptance or administration of this Trust  (including the reasonable
compensation and the expenses and disbursements of its agents and counsel),
except any such expense, disbursement or advance as may be attributable to its
negligence or bad faith; and

         (3) to indemnify the Trustee and its officers, directors, employees
and agents for, and to hold them harmless against, any and all loss, damage,
claim, liability or expense, including taxes (other than taxes based on the
income of the Trustee) incurred without negligence or bad faith on their part,
arising out of or in connection with the acceptance or administration of this
trust, including the costs and expenses of defending themselves against any
claim or liability in connection with the exercise or performance of any of its
powers or duties hereunder.

         The provisions of this Section shall survive the termination of this
Indenture or the resignation or removal of the Trustee.





                                       31
<PAGE>   38
SECTION 608.  Disqualification; Conflicting Interests.

         If the Trustee has or shall acquire a conflicting interest within the
meaning of the Trust Indenture Act, the Trustee shall either eliminate such
interest or resign, to the extent and in the manner provided by and subject to
the provisions of, the Trust Indenture Act and this Indenture.

SECTION 609.  Corporate Trustee Required; Eligibility.

         There shall at all times be a Trustee hereunder which shall be a
Person that is eligible pursuant to the Trust Indenture Act to act as such and
has a combined capital and surplus of at least $50,000,000 and has its
Corporate Trust Office in New York, New York, if such Person publishes reports
of condition at least annually, pursuant to law or to the requirements of said
supervising or examining authority, then for the purposes of this Section, the
combined capital and surplus of such Person shall be deemed to be its combined
capital and surplus as set forth in its most recent report of condition so
published.  If at any time the Trustee shall cease to be eligible in accordance
with the provisions of this Section, it shall resign immediately in the manner
and with the effect hereinafter specified in this Article.

SECTION 610.  Resignation and Removal; Appointment of Successor.

         (a) No resignation or removal of the Trustee and no appointment of a
successor Trustee pursuant to this Article shall become effective until the
acceptance of appointment by the successor Trustee under Section 611.

         (b) The Trustee may resign at any time by giving written notice
thereof to the Company.  If an instrument of acceptance by a successor Trustee
shall not have been delivered to the Trustee within 30 days after the giving of
such notice of resignation, the resigning Trustee may petition any court of
competent jurisdiction for the appointment of a successor Trustee.

         (c) The Trustee may be removed at any time by Act of the Holders of a
majority in principal amount of the Outstanding Securities, delivered to the
Trustee and to the Company.

         (d)  If at any time:

         (1) the Trustee shall fail to comply with Section 608 after written
request therefor by the Company or by any Holder who has been a bona fide
Holder of a Security for at least six months, or

         (2) the Trustee shall cease to be eligible under Section 609 and shall
fail to resign after written request therefor by the Company or by any such
Holder, or

         (3) the Trustee shall become incapable of acting or shall be adjudged
a bankrupt or insolvent or a receiver of the Trustee or of its property shall
be appointed or any public officer shall take charge or control of the Trustee
or of its property or affairs for the purpose of rehabilitation, conservation
or liquidation,





                                       32
<PAGE>   39
then, in any such case, (i) the Company by a Board Resolution may remove the
Trustee, or (ii) subject to Section 514, any Holder who has been a bona fide
Holder of a Security for at least six months may, on behalf of himself and all
others similarly situated, petition any court of competent jurisdiction for the
removal of the Trustee and the appointment of a successor Trustee.

         (e) If the Trustee shall resign, be removed or become incapable of
acting, or if a vacancy shall occur in the office of Trustee for any cause, the
Company, by a Board Resolution, shall promptly appoint a successor Trustee.
If, within one year after such resignation, removal or incapability, or the
occurrence of such vacancy, a successor Trustee shall be appointed by Act of
the Holders of a majority in principal amount of the Outstanding Securities
delivered to the Company and the retiring Trustee, the successor Trustee so
appointed shall, forthwith upon its acceptance of such appointment, become the
successor Trustee and supersede the successor Trustee appointed by the Company.
If no successor Trustee shall have been so appointed by the Company or the
Holders and accepted appointment in the manner hereinafter provided, any Holder
who has been a bona fide Holder of a Security for at least six months may, on
behalf of himself and all others similarly situated, petition any court of
competent jurisdiction for the appointment of a successor Trustee.

         (f) The Company shall give notice of each resignation and each removal
of the Trustee and each appointment of a successor Trustee to all Holders in
the manner provided in Section 106.  Each notice shall include the name of the
successor Trustee and the address of its Corporate Trust Office.

         (g) No retiring Trustee hereunder shall be liable for the acts or
omissions of any successor Trustee.

SECTION 611.  Acceptance of Appointment by Successor.

         Every successor Trustee appointed hereunder shall execute, acknowledge
and deliver to the Company and to the retiring Trustee an instrument accepting
such appointment, and thereupon the resignation or removal of the retiring
Trustee shall become effective and such successor Trustee, without any further
act, deed or conveyance, shall become vested with all the rights, powers,
trusts and duties of the retiring Trustee; provided that, on request of the
Company or the successor Trustee, such retiring Trustee shall, upon payment of
its fees, charges and expenses, execute and deliver an instrument transferring
to such successor Trustee all the rights, powers and trusts of the retiring
Trustee and shall duly assign, transfer and deliver to such successor Trustee
all property and money held by such retiring Trustee hereunder.  Upon request
of any such successor Trustee, the Company shall execute any and all
instruments for more fully and certainly vesting in and confirming to such
successor Trustee all such rights, powers and trusts.

         No successor Trustee shall accept its appointment unless at the time
of such acceptance such successor Trustee shall be qualified and eligible under
this Article.

SECTION 612.  Merger, Conversion, Consolidation or Succession to Business.

         Any corporation into which the Trustee may be merged or converted or
with which it may be consolidated, or any corporation resulting from any
merger, conversion or consolidation to which





                                       33
<PAGE>   40
the Trustee shall be a party, or any corporation succeeding to all or
substantially all the corporate trust business of the Trustee, shall be the
successor of the Trustee hereunder, provided such corporation shall be
otherwise qualified and eligible under this Article, without the execution or
filing of any paper or any further act on the part of any of the parties
hereto.  In case any Securities shall have been authenticated, but not
delivered, by the Trustee then in office, any successor by merger, conversion
or consolidation to such authenticating Trustee may adopt such authentication
and deliver the Securities so authenticated with the same effect as if such
successor Trustee had itself authenticated such Securities.

SECTION 613.  Preferential Collection of Claims Against Company.

         If and when the Trustee shall be or become a creditor of the Company,
the Trustee shall be subject to the provisions of the Trust Indenture Act
regarding the collection of claims against the Company (or any such other
obligor).

SECTION 614.  Character of Expenses.

         When the Trustee incurs expenses or renders services in connection
with an Event of Default, or any bankruptcy or insolvency in respect of the
Company, such expenses (including the fees and expenses of its counsel) and the
compensation for such services are intended to constitute expenses of
administration under any bankruptcy law or law relating to creditors' rights
generally.

                                 ARTICLE SEVEN

                     Holders' Lists and Reports by Trustee

SECTION 701.  Company to Furnish Trustee Names and Addresses of Holders.

         The Company will furnish or cause to be furnished to the Trustee

         (a) semiannually, not later than the last day of June and December in
each year, a list, in such form as the Trustee may reasonably require, of the
names and addresses of all Holders as of a date not more than 15 days prior to
the delivery thereof who were not Holders at the date of the Company had
previously provided such list (or, in the case of the initial provision of such
list, at the date of issuance of the Securities), and

         (b) at such other times as the Trustee may request in writing, within
30 days after the receipt by the Company of any such request, a list of similar
form and content as of a date not more than 15 days prior to the time such list
is furnished, excluding from any such list names and addresses received by the
Trustee in its capacity as Security Registrar.

SECTION 702.  Preservation of Information; Communications to Holders.

         (a) The Trustee shall preserve, in as current a form as is reasonably
practicable, the names and addresses of Holders contained in the most recent
list furnished to the Trustee as provided in





                                       34
<PAGE>   41
Section 701 and the names and addresses of Holders received by the Trustee in
its capacity as Security Registrar.  The Trustee may destroy any list furnished
to it as provided in Section 701 upon receipt of a new list so furnished.

         (b) The rights of Holders to communicate with other Holders with
respect to their rights under this Indenture or under the Securities, and the
corresponding rights and duties of the Trustee, shall be as provided by the
Trust Indenture Act.

         (c) Every Holder of Securities, by receiving and holding the same,
agrees with the Company and the Trustee that neither the Company nor the
Trustee nor any agent of any of them shall be held accountable by reason of any
disclosure of information as to names and addresses of Holders made pursuant to
the Trust Indenture Act.

SECTION 703.  Reports by Trustee.

         (a) The Trustee shall transmit to Holders such reports concerning the
Trustee and its actions under this Indenture as may be required pursuant to the
Trust Indenture Act at the times and in the manner provided pursuant thereto.

         (b) A copy of each such report shall, at the time of such transmission
to Holders, be filed by the Trustee with each stock exchange upon which the
Securities are listed, and with the Company.  The Company will notify the
Trustee when the Securities are listed on any stock exchange.

                                 ARTICLE EIGHT

              Consolidation, Merger, Conveyance, Transfer or Lease

SECTION 801.  Company May Consolidate, Etc., Only on Certain Terms.

         The Company covenants that it will not merge or consolidate with any
other corporation or other entity or sell or convey all or substantially all of
its assets to any person (other than such a sale or conveyance to a Subsidiary
or any successor thereto (such a sale or conveyance being called an "Asset
Drop-Down")), unless (i) either the Company shall be the continuing corporation
or the successor corporation or other entity or the person which acquires by
sale or conveyance substantially all the assets of the Company shall expressly
assume the due and punctual payment of the principal of, premium, if any, and
interest, if any, on all the Securities, according to their tenor, and the due
and punctual performance and observance of all of the covenants and conditions
of this Indenture to be performed or observed by the Company, by supplemental
indenture in form satisfactory to the Trustee, executed and delivered to the
Trustee by such corporation or other entity, and (ii) the Company or such
successor corporation or other entity, as the case may be, shall not,
immediately after such merger or consolidation, or such sale or conveyance, be
in default in the performance of any such covenant or condition.  In the event
of any Asset Drop-Down after the date of this Indenture, any subsequent sale or
conveyance of assets by a Subsidiary to which assets were transferred in such
Asset Drop-Down (a "Drop-Down Subsidiary") will be deemed to be a sale or
conveyance of assets by the Company for purposes of this Section 801.





                                       35
<PAGE>   42
SECTION 802.  Successor Substituted.

         In case of any such consolidation, merger, sale or conveyance, and
following such an assumption by the successor corporation, such successor
corporation shall succeed to and be substituted for the Company, with the same
effect as if it had been named herein.  Such successor corporation may cause to
be signed, and may issue either in its own name or in the name of the Company
prior to such succession any or all of the Securities issuable hereunder which
theretofore shall not have been signed by the Company and delivered to the
Trustee; and, upon the order of such successor corporation instead of the
Company and subject to all the terms, conditions and limitations in this
Indenture prescribed, the Trustee shall authenticate and shall deliver any
Securities which previously shall have been signed and delivered by the
officers of the Company to the Trustee for authentication, and any Securities
which such successor corporation thereafter shall cause to be signed and
delivered to the Trustee for that purpose.  All of the Securities so issued
shall in all respects have the same legal rank and benefit under this Indenture
as the Securities theretofore or thereafter issued in accordance with the terms
of this Indenture as though all of such Securities had been issued at the date
of the execution hereof.

         In case of any such consolidation, merger, sale, lease or conveyance
such changes in phraseology and form (but not in substance) may be made in the
Securities thereafter to be issued as may be appropriate.

         In the event of any such sale or conveyance (other than a conveyance
by way of lease) the Company or any successor corporation which shall
theretofore have become such in the manner described in this Article shall be
released and discharged from all obligations and covenants under this
Indenture.

                                  ARTICLE NINE

                            Supplemental Indentures

SECTION 901.  Supplemental Indentures Without Consent of Holders.

         Without the consent of any Holders, the Company, when authorized by a
Board Resolution, and the Trustee, at any time and from time to time, may enter
into one or more indentures supplemental hereto, in form satisfactory to the
Trustee, for any of the following purposes:

         (1) to evidence the succession of another Person to the Company and
the assumption by any such successor of the covenants of the Company herein and
in the Securities;

         (2) to add to the covenants of the Company for the benefit of the
Holders, or to surrender any right or power herein or in the Securities
conferred upon the Company;

         (3) to cure any ambiguity or to correct any provision herein which may
be defective or inconsistent with any other provision herein;





                                       36
<PAGE>   43
         (4) to comply with the requirements of the Commission in order to
effect or maintain the qualification of this Indenture under the Trust
Indenture Act, as contemplated by Section 905 or otherwise;

         (5) to evidence and provide the acceptance of the appointment of a
successor Trustee hereunder; or

         (6) to make any other change that does not adversely affect the rights
of any Holder.

SECTION 902.  Supplemental Indentures with Consent of Holders.

         With the consent of the Holders of not less than a majority in
principal amount of the Outstanding Securities, by Act of said Holders
delivered to the Company and the Trustee, the Company, when authorized by a
Board Resolution, and the Trustee may enter into an indenture or indentures
supplemental hereto for the purpose of adding any provisions to or changing in
any manner or eliminating any of the provisions of this Indenture or of
modifying in any manner the rights of the Holders under this Indenture;
provided, however, that no such supplemental indenture shall, without the
consent of the Holder of each Outstanding Security affected thereby,

         (1) change the Stated Maturity of the principal of, or any installment
of interest (including any Additional Interest) on, any Security, or reduce the
principal amount thereof or the rate of interest thereon, or change the place
of payment where, or the coin or currency in which, any Security or interest
thereon is payable, or impair the right to institute suit for the enforcement
of any such payment on or after the Stated Maturity thereof (or, in the case of
redemption, on or after the Redemption Date), or modify the provisions of this
Indenture with respect to the subordination of the Securities in a manner
adverse to the Holders,

         (2) reduce the percentage in principal amount of the Outstanding
Securities, the consent of whose Holders is required for any such supplemental
indenture, or the consent of whose Holders in required for any waiver (of
compliance with certain provisions of this Indenture or certain defaults
hereunder and their consequences) provided for in this Indenture, or

         (3) modify any of the provisions of this Section or Section 513,
except to increase any such percentage or to provide that certain other
provisions of this Indenture cannot be modified or waived without the consent
of the Holder of each Outstanding Security affected thereby.

         It shall not be necessary for any Act of Holders under this Section to
approve the particular form of any proposed supplemental indenture, but it
shall be sufficient if such Act shall approve the substance thereof.

SECTION 903.  Execution of Supplemental Indentures.

         In executing, or accepting the additional trusts created by, any
supplemental indenture permitted by this Article or the modifications thereby
of the trusts created by this Indenture, the Trustee shall be entitled to
receive, and (subject to Section 601) shall be fully protected in relying





                                       37
<PAGE>   44
upon an Officer's Certificate stating that all conditions precedent to the
execution of such supplemental indenture have been fulfilled and an Opinion of
Counsel stating that the execution of such supplemental indenture is authorized
or permitted by this Indenture.  The Trustee may, but shall not be obligated
to, enter into any such supplemental indenture which affects the Trustee's own
rights, duties or immunities under this Indenture or otherwise.

SECTION 904.  Effect of Supplemental Indentures.

         Upon the execution of any supplemental indenture under this Article,
this Indenture shall be modified in accordance therewith, and such supplemental
indenture shall form a part of this Indenture for all purposes; and every
Holder of Securities theretofore or thereafter authenticated and delivered
hereunder shall be bound thereby.

SECTION 905.  Conformity with Trust Indenture Act.

         Every supplemental indenture executed pursuant to this Article shall
conform to the requirements of the Trust Indenture Act.

                                  ARTICLE TEN

                   Covenants; Representations and Warranties

SECTION 1001.  Payment of Principal and Interest.

         The Company will duly and punctually pay the principal of and interest
on the Securities in accordance with the terms of the Securities and this
Indenture.

SECTION 1002.  Maintenance of Office or Agency.

         The Company will maintain in New York, New York, an office or agency
where Securities may be presented or surrendered for payment, where Securities
may be surrendered for registration of transfer or exchange and where notices
and demands to or upon the Company in respect of the Securities and this
Indenture may be served.  The Company will give prompt written notice to the
Trustee of the location, and any change in the location, of such office or
agency.  If at any time the Company shall fail to maintain any such required
office or agency or shall fail to furnish the Trustee with the address thereof,
such presentations, surrenders, notices and demands may be made or served at
the Corporate Trust Office of the Trustee, and the Company hereby appoints the
Trustee as its agent to receive all such presentations, surrenders, notices and
demands.

         The Company may also from time to time designate one or more other
offices or agencies in the United States where the Securities may be presented
or surrendered for any or all such purposes and may from time to time rescind
such designations; provided, however, that no such designation or rescission
shall in any manner relieve the Company of its obligation to maintain an office
or agency in New York, New York for such purposes.  The Company will give
prompt written





                                       38
<PAGE>   45
notice to the Trustee of any such designation or rescission and of any change
in the location of any such other office or agency.

SECTION 1003.  Money for Security Payments to Be Held in Trust.

         If the Company shall at any time act as its own Paying Agent, it will,
on or at the option of the Company before each due date of the principal of or
interest on any of the Securities, segregate and hold in trust for the benefit
of the Persons entitled thereto a sum sufficient to pay the principal or
interest so becoming due until such sums shall be paid to such Persons or
otherwise disposed of as herein provided and will promptly notify the Trustee
of its action or failure so to act.

         Whenever the Company shall have one or more Paying Agents, it will, on
or prior to each due date of the principal of or interest on any Securities,
deposit with a Paying Agent a sum sufficient to pay such amount, such sum to be
held as provided by the Trust Indenture Act, and (unless such Paying Agent is
the Trustee) the Company will promptly notify the Trustee of its action or
failure so to act.

         Any money deposited with the Trustee or any Paying Agent, or then held
by the Company, in trust for the payment of the principal of or interest on any
Security and remaining unclaimed for two years after such principal or interest
has become due and payable shall be paid to the Company on a Company Request,
or (if then held by the Company) shall be discharged from such trust; and the
Holder of such Security shall thereafter, as an unsecured general creditor,
look only to the Company for payment thereof, and all liability of the Trustee
or such Paying Agent with respect to such trust money, and all liability of the
Company as trustee thereof, shall thereupon cease.

SECTION 1004.  Reports by the Company.

         The Company shall file with the Trustee and the Commission, and
transmit to Holders, such information, documents and other reports, and such
summaries thereof, as may be required pursuant to the Trust Indenture Act at
the times and in the manner provided pursuant to such Act; provided that any
such information, documents or reports required to be filed with the Commission
pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 shall be
filed with the Trustee within 15 days after the same is so required to be filed
with the Commission.  Delivery of such reports, information and documents to
the Trustee is for informational purposes only and the Trustee's receipt of
such shall not constitute constructive notice of any information contained
therein or determinable from information contained therein, including the
Company's compliance with any of its covenants hereunder (as to which the
Trustee is entitled to rely exclusively on Officers' Certificates).

SECTION 1005.  Negative Pledge and Exceptions Thereto.

         So long as any of the Securities are outstanding, the Company will not
pledge, mortgage or hypothecate, or permit to exist, and will not cause, suffer
or permit any Subsidiary to pledge, mortgage or hypothecate, or permit to
exist, except in favor of the Company or any Subsidiary, any mortgage, pledge
or other lien upon, any Principal Property at any time owned by it, to secure





                                       39
<PAGE>   46
any indebtedness, without making effective provisions whereby the Securities
shall be equally and ratably secured with any and all such indebtedness and
with any other indebtedness similarly entitled to be equally and ratably
secured; provided, however, that this restriction shall not apply to or prevent
the creation or existence of:

                 (a)      undetermined or inchoate liens and charges incidental
         to construction, maintenance, development or operation;

                 (b)      the lien of taxes and assessments for the then
         current year;

                 (c)      the lien of taxes and assessments not at the time
         delinquent;

                 (d)      the lien of specified taxes and assessments which are
         delinquent but the validity of which is being contested at the time by
         the Company or such Subsidiary in good faith;

                 (e)      the lien reserved in leases for rent and for
         compliance with the terms of the lease in the case of leasehold
         estates;

                 (f)      any obligations or duties, affecting the property of
         the Company or such Subsidiary, to any municipality or public
         authority with respect to any franchise, grant, license, permit or
         similar arrangement;

                 (g)      the liens of any judgments or attachments in an
         aggregate amount not in excess of $10,000,000, or the lien of any
         judgment or attachment the execution or enforcement of which has been
         stayed or which has been appealed and secured, if necessary, by the
         filing of an appeal bond;

                 (h)      any mortgage, pledge, lien or encumbrance on any
         property held or used by the Company or a Subsidiary in connection
         with the exploration for, development of or production of oil, gas,
         natural gas (including liquified gas or storage gas), other
         hydrocarbons, helium, coal, metals, minerals, steam, timber,
         geothermal or other natural resources or synthetic fuels, such
         properties to include, but not be limited to, the Company's or a
         Subsidiary's interest in any mineral fee interests, oil, gas or other
         mineral leases, royalty, overriding royalty or net profits interests,
         production payments and other similar interests, wellhead production
         equipment, tanks, field gathering lines, leasehold or field separation
         and processing facilities, compression facilities and other similar
         personal property and fixtures;

                 (i)      any mortgage, pledge, lien or encumbrance on oil,
         gas, natural gas (including liquified gas and storage gas), and other
         hydrocarbons, helium, coal, metals, minerals, steam, timber,
         geothermal or other natural resources or synthetic fuels produced or
         recovered from any property, an interest in which is owned or leased
         by the Company or a Subsidiary;





                                       40
<PAGE>   47
                 (j)      mortgages, pledges, liens or encumbrances upon any
         property heretofore or hereafter acquired, created at the time of
         acquisition or within one year thereafter to secure all or a portion
         of the purchase price thereof, or existing thereon at the date of
         acquisition, whether or not assumed by the Company or a Subsidiary,
         provided that every such mortgage, pledge, lien or encumbrance shall
         apply only to the property so acquired and fixed improvements thereon;

                 (k)      any extension, renewal or refunding, in whole or in
         part, of any mortgage, pledge, lien or encumbrance permitted by
         subparagraph (j) above, if limited to the same property or any portion
         thereof subject to, and securing not more than the amount secured by,
         the mortgage, pledge, lien or encumbrance extended, renewed or
         refunded;

                 (l)      mortgages, pledges, liens or encumbrances upon any
         property heretofore or hereafter acquired by any corporation that is
         or becomes a Subsidiary after the date hereof ("Acquired Entity"),
         provided that every such mortgage, pledge, lien or encumbrance (1)
         shall either (A) exist prior to the time the Acquired Entity becomes a
         Subsidiary or (B) be created at the time the Acquired Entity becomes a
         Subsidiary or within one year thereafter to secure all or a portion of
         the acquisition price thereof and (2) shall only apply to those
         properties owned by the Acquired Entity at the time it becomes a
         Subsidiary or thereafter acquired by it from sources other than the
         Company or any other Subsidiary;

                 (m)      the pledge of current assets, in the ordinary course
         of business, to secure current liabilities;

                 (n)      mechanics' or materialmen's liens, any liens or
         charges arising by reason of pledges or deposits to secure payment of
         workmen's compensation or other insurance, good faith deposits in
         connection with tenders, leases of real estate, bids or contracts
         (other than contracts for the payment of money), deposits to secure
         duties or public or statutory obligations, deposits to secure, or in
         lieu of, surety, stay or appeal bonds, and deposits as security for
         the payment of taxes or assessments or similar charges;

                 (o)      any lien arising by reason of deposits with, or the
         giving of any form of security to, any governmental agency or any body
         created or approved by law or governmental regulation for any purpose
         at any time in connection with the financing of the acquisition or
         construction of property to be used in the business of the Company or
         a Subsidiary or as required by law or governmental regulation as a
         condition to the transaction of any business or the exercise of any
         privilege or license, or to enable the Company or a Subsidiary to
         maintain self-insurance or to participate in any funds established to
         cover any insurance risks or in connection with workmen's
         compensation, unemployment insurance, old age pensions or other social
         security, or to share in the privileges or benefits required for
         companies participating in such arrangements;

                 (p)      any lien to secure indebtedness other than Funded
         Debt;





                                       41
<PAGE>   48
                 (q)      any mortgage, pledge, lien or encumbrance of or upon
         any office equipment, data processing equipment (including, without
         limitation, computer and computer peripheral equipment), or
         transportation equipment (including, without limitation, motor
         vehicles, tractors, trailers, marine vessels, barges, towboats,
         rolling stock and aircraft);

                 (r)      any mortgage, pledge, lien or encumbrance created or
         assumed by the Company or a Subsidiary in connection with the issuance
         of debt securities the interest on which is excludable from gross
         income of the holder of such security pursuant to the Internal Revenue
         Code of 1954, as amended, for the purpose of financing, in whole or in
         part, the acquisition or construction of property to be used by the
         Company or a Subsidiary; or

                 (s)      the pledge or assignment of accounts receivable, or
         the pledge or assignment of conditional sales contracts or chattel
         mortgages and evidences of indebtedness secured thereby, received in
         connection with the sale by the Company or such Subsidiary or others
         of goods or merchandise to customers of the Company or such
         Subsidiary.

         In case the Company or any Subsidiary shall propose to pledge,
mortgage or hypothecate any Principal Property at any time owned by it to
secure any indebtedness, other than as permitted by subdivisions (a) to (s),
inclusive, of this Section 1005, the Company will prior thereto give written
notice thereof to the Trustee, and the Company will, or will cause such
Subsidiary to, prior to or simultaneously with such pledge, mortgage or
hypothecation, enter into a supplemental with the Trustee (or to the extent
legally necessary to another trustee or additional or separate trustee) that
secures all the Securities equally and ratably with such indebtedness.

         Notwithstanding the foregoing provisions of this Section 1005, the
Company or a Subsidiary may issue, assume or guarantee indebtedness secured by
mortgage which would otherwise be subject to the foregoing restrictions in an
aggregate amount which, together with all other indebtedness of the Company or
a Subsidiary secured by a mortgage which (if originally issued, assumed or
guaranteed at such time) would otherwise be subject to the foregoing
restrictions (not including indebtedness permitted to be secured under clauses
(a) through (s) above), does not at the time exceed 10% of the Consolidated Net
Tangible Assets of the Company, as shown on the audited consolidated financial
statements of the Company as of the end of the fiscal year preceding the date
of determination.

SECTION 1006.  Statement as to Compliance; Notice of Certain Events of Default.

         The Company will, within 120 days after the close of each fiscal year,
commencing with the first fiscal year following the issuance of Securities
under this Indenture, file with the Trustee a certificate of the principal
executive officer, the principal financial officer or the principal accounting
officer of the Company covering the period from the date of issuance of such
Securities to the end of the fiscal year in which such Securities were issued,
in the case of the first such certificate, andcovering the preceding fiscal
year in the case of each subsequent certificate, and stating whether or





                                       42
<PAGE>   49
not, to the knowledge of the signer, the Company has complied with all
conditions and covenants on its part contained in this Indenture, and, if the
signer has obtained knowledge of any default by the Company in the performance,
observance or fulfillment of any such condition or covenant, specifying each
such default and the nature thereof.  For the purpose of this Section 1007,
compliance shall be determined without regard to any grace period or
requirement of notice provided pursuant to the terms of this Indenture.

                                 ARTICLE ELEVEN

                          Subordination of Securities

SECTION 1101.  Securities Subordinate to Senior Indebtedness.

         The Company covenants and agrees, and each Holder of a Security, by
his acceptance thereof, likewise covenants and agrees, that, notwithstanding
anything to the contrary contained herein, to the extent and in the manner
hereinafter set forth in this Article, the indebtedness represented by the
Securities and the payment of the principal of and premium, if any, and
interest on each and all of the Securities are hereby expressly made
subordinate and subject in right of payment to the prior payment in full in
cash or cash equivalents of all Senior Indebtedness (including any interest
accruing after the occurrence of an Event of Default under Section 501(4) or
(5)).

SECTION 1102.  Payment Over of Proceeds upon Dissolution, etc.

         In the event of (a) any insolvency or bankruptcy case or proceeding,
or any receivership, liquidation, reorganization or other similar case or
proceeding in connection therewith, relative to the Company or to its
creditors, as such, or to its assets, or (b) any liquidation, dissolution or
other winding up of the Company, whether voluntary or involuntary and whether
or not involving insolvency or bankruptcy, or (c) any assignment for the
benefit of creditors or any other marshalling of assets and liabilities of the
Company, then and in any such event:

         (1) the holders of Senior Indebtedness shall be entitled to receive
payment in full in cash or cash equivalents of all amounts due or to become due
on or in respect of all Senior Indebtedness, or provision shall be made for
such payment in cash or cash equivalents, before the Holders of the Securities
are entitled to receive any payment on account of principal of (or premium, if
any) or interest on the Securities; and

         (2) any payment or distribution of assets of the Company of any kind
or character, whether in cash, property or securities, by set-off or otherwise,
to which the Holders or the Trustee would be entitled but for the provisions of
this Article Eleven, including any such payment or distribution which may be
payable or deliverable by reason of the payment of any other indebtedness of
the Company being subordinated to the payment of the Securities (except for any
such payment or distribution of securities which (i) are unsecured, (ii) have
an average life and final maturity no shorter than the average life and final
maturity of the Securities and (iii) are subordinated, to at least the same
extent as the Securities, to the payment of all Senior Indebtedness then
outstanding), shall be paid by the liquidating trustee or agent or other person
making such payment or distribution,





                                       43
<PAGE>   50
whether a trustee in bankruptcy, a receiver or liquidating trustee or
otherwise, directly to the holders of Senior Indebtedness or their
Representative or Representatives or to the trustee or trustees under any
indenture under which any instruments evidencing any of such Senior
Indebtedness may have been issued, ratably according to the aggregate amounts
remaining unpaid on account of the principal of, and premium, if any, and
interest on, and other amounts due on or in connection with, the Senior
Indebtedness to the extent necessary to make payment in full in cash or cash
equivalents of all Senior Indebtedness remaining unpaid, after giving effect to
any concurrent payment or distribution to the holders of such Senior
Indebtedness; and

         (3) in the event that, notwithstanding the foregoing provisions of
this Section, the Trustee or the Holder of any Security shall have received any
such payment or distribution of assets of the Company of any kind or character,
whether in cash, property or securities, including any such payment or
distribution which may be payable or deliverable by reason of the payment of
any other indebtedness of the Company being subordinated to the payment of the
Securities, before all Senior Indebtedness is paid in full or payment thereof
provided for, then and in such event such payment or distribution shall be paid
over or delivered forthwith to the trustee in bankruptcy, receiver, liquidating
trustee, custodian, assignee, agent or other Person making payment or
distribution of assets of the Company for application to the payment of all
Senior Indebtedness remaining unpaid to the extent necessary to pay all Senior
Indebtedness in full in cash or cash equivalents, after giving effect to any
concurrent payment or distribution to or for the holders of Senior
Indebtedness.

         The consolidation of the Company with, or the merger of the Company
into, another corporation or the liquidation or dissolution of the Company
following the conveyance, transfer or lease of its properties and assets
substantially as an entirety to another corporation upon the terms and
conditions set forth in Article Eight shall not be deemed a dissolution,
winding up, liquidation, reorganization, assignment for the benefit of
creditors or marshalling of assets and liabilities of the Company for the
purposes of this Section if the corporation formed by such consolidation or
into which the Company is merged or the corporation which acquires by
conveyance, transfer or lease such properties and assets substantially as an
entirety, as the case may be, shall, as a part of such consolidation, merger,
conveyance, transfer or lease, comply with the conditions set forth in Article
Eight.

SECTION 1103.  No Payment When Senior Indebtedness in Default.

         No payment of principal (including redemption payments), premium, if
any, or interest on the Securities may be made (i) if any Senior Indebtedness
is not paid when due, (ii) if any applicable grace period with respect to such
payment default on Senior Indebtedness has ended and such default has not been
cured or waived or ceased to exist, or (iii) if the maturity of any Senior
Indebtedness of the Company has been accelerated because of a default.

         In the event that, notwithstanding the foregoing, the Company shall
make any payment to the Trustee or the Holder of any Security prohibited by the
foregoing provisions of this Section, then and in such event such payment shall
be received and held in trust for the holders of Senior Indebtedness and shall
be paid over or delivered to the Representative of Senior Indebtedness then
outstanding to the extent necessary to pay in full in cash or cash equivalents
all Senior Indebtedness.





                                       44
<PAGE>   51
         The provisions of this Section shall not apply to any payment with
respect to which Section 1102 would be applicable.

SECTION 1104.  Payment Permitted If No Default.

         Nothing contained in this Article or elsewhere in this Indenture or in
any of the Securities shall prevent the Company, at any time except during the
pendency of any case, proceeding, dissolution, liquidation or other winding up,
assignment for the benefit of creditors or other marshalling of assets and
liabilities of the Company referred to in Section 1102 or under the conditions
described in Section 1103, from making payments at any time of principal of
(and premium, if any) or interest on the Securities.

SECTION 1105.  Subrogation to Rights of Holders of Senior Indebtedness.

         Subject to the payment in full of all Senior Indebtedness, the Holders
of the Securities shall be subrogated (equally and ratably with the holders of
all indebtedness of the Company which by its express terms is subordinated to
Senior Indebtedness of the Company to the same extent as the Securities are
subordinated and which is entitled to like rights of subrogation) to the rights
of the holders of such Senior Indebtedness to receive payments and
distributions of cash, property and securities applicable to the Senior
Indebtedness until the principal of (and premium, if any) and interest on the
Securities shall be paid in full.  For purposes of such subrogation, no
payments or distributions to the holders of Senior Indebtedness of any cash,
property or securities to which the Holders of the Securities or the Trustee
would be entitled except for the provisions of this Article, and no payments
over pursuant to the provisions of this Article to the holders of Senior
Indebtedness by Holders of the Securities or the Trustee, shall, as among the
Company, its creditors other than holders of Senior Indebtedness, and the
Holders of the Securities, be deemed to be a payment or distribution by the
Company to or on account of the Senior Indebtedness.

SECTION 1106.  Provisions Solely to Define Relative Rights.

         The provisions of this Article are and are intended solely for the
purpose of defining the relative rights of the Holders of the Securities on the
one hand and the holders of Senior Indebtedness on the other hand.  Nothing
contained in this Article or elsewhere in this Indenture or in the Securities
is intended to or shall (a) impair, as among the Company, its creditors other
than holders of Senior Indebtedness and the Holders of the Securities, the
obligation of the Company, which is absolute and unconditional, to pay to the
Holders of the Securities the principal of (and premium, if any) and interest
on the Securities as and when the same shall become due and payable in
accordance with their terms; or (b) affect the relative rights against the
Company of the Holders of the Securities and creditors of the Company other
than the holders of Senior Indebtedness; or (c) prevent the Trustee or the
Holder of any Security from exercising all remedies otherwise permitted by
applicable law upon default under this Indenture, subject to the express
limitations set forth in Article Five and to the rights, if any, under this
Article of the holders of Senior Indebtedness (1) in any case, proceeding,
dissolution, liquidation or other winding up, assignment for the benefit of
creditors or other marshalling of assets and liabilities of the Company
referred to in Section 1102, to receive, pursuant to and in accordance with
such Section, cash, property and securities otherwise





                                       45
<PAGE>   52
payable or deliverable to the Trustee or such Holder, or (2) under the
conditions specified in Section 1103, to prevent any payment prohibited by such
Section.

SECTION 1107.  Trustee to Effectuate Subordination.

         Each Holder of a Security by his acceptance thereof authorizes and
directs the Trustee on his behalf to take such action as may be necessary or
appropriate to effectuate the subordination provided in this Article and
appoints the Trustee his attorney-in-fact for any and all such purposes.
SECTION 1108.  No Waiver of Subordination Provisions.

         No right of any present or future holder of any Senior Indebtedness to
enforce subordination as herein provided shall at any time in any way be
prejudiced or impaired by any act or failure to act on the part of the Company
or by any act or failure to act, in good faith, by any such holder, or by any
non-compliance by the Company with the terms, provisions and covenants of this
Indenture, regardless of any knowledge thereof any such holder may have or be
otherwise charged with.

         Without in any way limiting the generality of the foregoing paragraph,
the holders of Senior Indebtedness may, at any time and from time to time,
without the consent of or notice to the Trustee or the Holders of the
Securities, without incurring responsibility to the Holders of the Securities
and without impairing or releasing the subordination provided in this Article
or the obligations hereunder of the Holders of the Securities to the holders of
Senior Indebtedness, do any one or more of the following: (a) change the
manner, place or terms of payment or extend the time of payment of, or renew or
alter, Senior Indebtedness or any instrument evidencing the same or any
agreement under which Senior Indebtedness is outstanding; (b) sell, exchange,
release or otherwise deal with any property pledged, mortgaged or otherwise
securing Senior Indebtedness; (c) release any Person liable in any manner for
the collection of Senior Indebtedness; and (d) exercise or refrain from
exercising any rights against the Company and any other Person.

SECTION 1109.  Notice to Trustee.

         The Company shall give prompt written notice to the Trustee of any
fact known to the Company which would prohibit the making of any payment to or
by the Trustee in respect of the Securities.  Notwithstanding the provisions of
this Article or any other provision of this Indenture, the Trustee shall not be
charged with knowledge of the existence of any facts which would prohibit the
making of any payments to or by the Trustee in respect of the Securities,
unless and until the Trustee shall have received written notice thereof at the
Corporate Trust Office of the Trustee from the Company or a holder of Senior
Indebtedness or from any trustee, fiduciary or agent therefor; and, prior to
the receipt of any such written notice, the Trustee, subject to the provisions
of Section 603, shall be entitled in all respects to assume that no such facts
exist; provided, however, that if the Trustee shall not have received the
notice provided for in this Section 1109 at least three Business Days prior to
the date upon which by the terms hereof any money may become payable for any
purpose (including, without limitation, the payment of the principal of (and
premium, if any) or interest on any Security), then, anything herein contained
to the contrary notwithstanding, the Trustee shall have full power and
authority to receive such money and to apply the same to the purpose for





                                       46
<PAGE>   53
which such money was received and shall not be affected by any notice to the
contrary which may be received by it within three Business Days prior to such
date.  Nothing in this Section 1109 shall limit the right of the holders of
Senior Indebtedness to recover payments as contemplated by Section 1102 and
1103.

         Subject to the provisions of Section 603, the Trustee shall be
entitled to rely on the delivery to it of a written notice by a Person
representing himself to be a holder of Senior Indebtedness (or a trustee,
fiduciary or agent therefor) to establish that such notice has been given by a
holder of Senior Indebtedness (or a trustee, fiduciary or agent therefor).  In
the event that the Trustee determines in good faith that further evidence is
required with respect to the right of any Person as a holder of Senior
Indebtedness to participate in any payment or distribution pursuant to this
Article, the Trustee may request such Person to furnish evidence to the
reasonable satisfaction of the Trustee as to the amount of Senior Indebtedness
held by such Person, the extent to which such Person is entitled to participate
in such payment or distribution and any other facts pertinent to the rights of
such Person under this Article, and if such evidence is not furnished, the
Trustee may defer any payment to such Person pending judicial determination as
to the right of such Person to receive such payment.

SECTION 1110.  Reliance on Judicial Order or Certificate of Liquidating Agent.

         Upon any payment or distribution of assets of the Company referred to
in this Article, the Trustee, subject to the provisions of Section 603, and the
Holders of the Securities shall be entitled to rely upon any order or decree
entered by any court of competent jurisdiction in which such insolvency,
bankruptcy, receivership, liquidation, reorganization, dissolution, winding up
or similar case or proceeding is pending, or a certificate of the trustee in
bankruptcy, receiver, liquidating trustee, custodian, assignee for the benefit
of creditors, agent or other Person making such payment or distribution,
delivered to the Trustee or to the Holders of Securities, for the purpose of
ascertaining the Persons entitled to participate in such payment or
distribution, the holders of Senior Indebtedness and other indebtedness of the
Company, the amount thereof or payable thereon, the amount or amounts paid or
distributed thereon and all other facts pertinent thereto or to this Article.
SECTION 1111.  Rights of Trustee as a Holder of Senior Indebtedness;
Preservation of Trustee's Rights.

         The Trustee in its individual capacity shall be entitled to all the
rights set forth in this Article with respect to any Senior Indebtedness which
may at any time be held by it, to the same extent as any other holder of Senior
Indebtedness, and nothing in this Indenture shall deprive the Trustee of any of
its rights as such holder.

         Nothing in this Article shall apply to claims of, or payments to, the
Trustee under or pursuant to Section 607.





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<PAGE>   54
SECTION 1112.  Article Applicable to Paying Agents.

         In case at any time any Paying Agent other than the Trustee shall have
been appointed by the Company and be then acting hereunder, the term "Trustee"
as used in this Article shall in such case (unless the context otherwise
requires) be construed as extending to and including such Paying Agent within
its meaning as fully for all intents and purposes as if such Paying Agent were
named in this Article in addition to or in place of the Trustee; provided,
however, that (i) Section 1111 shall not apply to the Company or any Affiliate
of the Company if it or such Affiliate acts as Paying Agent and (ii) any notice
required by this Article Eleven to be given by the holders of, or a
Representative for, Senior Indebtedness need only be given to the Trustee and
not to any Paying Agent.

                                 ARTICLE TWELVE

                            Redemption of Securities

SECTION 1201.  Optional Redemption.

         (a) At any time on or after December 31, 2001, the Company shall have
the right to redeem the Securities, in whole or in part, from time to time, at
a Redemption Price equal to 100% of the principal amount of Securities to be
redeemed plus accrued but unpaid interest, including any Additional Interest,
if any, to the Redemption Date.

         (b) If, at any time, a Partnership Tax Event or a Partnership
Investment Company Event (each a "Partnership Special Event") shall occur and
be continuing, the Company may, within 90 days following the occurrence of such
Partnership Special Event, elect to redeem the Securities in whole (but not in
part), upon not less than 30 or more than 60 days' notice at the Redemption
Price, provided that, if at the time there is available to the Company or the
Partnership the opportunity to eliminate, within such 90-day period, the
Partnership Special Event by taking some ministerial action, such as filing a
form or making an election, or pursuing some other similar reasonable such
measure that in the sole judgment of the Company has or will cause no adverse
effect on the Partnership, the Trust or the Company, the Company will pursue
such measure in lieu of redemption.  SECTION 1202.  Applicability of Article.

         Redemption of Securities, at the election of the Company as permitted
by Section 1201, shall be made in accordance with such provision and this
Article.

SECTION 1203.  Authorization for Redemption; Notice to Trustee.

         The election of the Company to redeem Securities pursuant to Section
1201 shall be evidenced by a Board Resolution.  In case of any redemption, the
Company shall, at least 30 days and no more than 60 days prior to the
Redemption Date fixed by the Company, notify the Trustee of such Redemption
Date and of the principal amount of Securities to be redeemed and provide a
copy of the notice of redemption given to Holders of Securities to be redeemed
pursuant to Section 1204.





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<PAGE>   55
SECTION 1204.  Selection by Trustee of Securities to Be Redeemed.

         If less than all the Securities are to be redeemed (unless such
redemption affects only a single Security), the particular Securities to be
redeemed shall be selected not more than 60 days prior to the Redemption Date
by the Trustee, from the Outstanding Securities not previously called for
redemption, by such method (including pro rata or by lot) as the Trustee shall
deem fair and appropriate and which may provide for the selection for
redemption of portions (equal to $25 or any integral multiple thereof) of the
principal amount of the Securities.

         The Trustee shall promptly notify the Company in writing of the
Securities selected for redemption as aforesaid and, in case of any Securities
selected for partial redemption as aforesaid, the principal amount thereof to
be redeemed.

         The provisions of the two preceding paragraphs shall not apply with
respect to any redemption affecting only a single Security, whether such
Security is to be redeemed in whole or in part.  In the case of any such
redemption in part, the unredeemed portion of the principal amount of the
Security shall be in an authorized denomination (which shall not be less than
the minimum authorized denomination) for such Security.

         For all purposes of this Indenture, unless the context otherwise
requires, all provisions relating to the redemption of Securities shall relate,
in the case of any Securities redeemed or to be redeemed only in part, to the
portion of the principal amount of such Securities which has been or is to be
redeemed.

SECTION 1205.  Notice of Redemption.

         Notice of redemption shall be given by first-class mail, postage
prepaid, mailed not less than 30 nor more than 60 days prior to the Redemption
Date, to each Holder of Securities to be redeemed, at his address appearing in
the Security Register.

         All notices of redemption shall identify the Securities to be redeemed
and shall state:

         (1) the Redemption Date,

         (2) the Redemption Price,

         (3) that on the Redemption Date the Redemption Price will become due
and payable upon each such security to be redeemed and that interest thereon
will cease to accrue on and after said date, and

         (4) the place or places where such securities are to be surrendered
for payment of the Redemption Price.





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<PAGE>   56
         Notice of redemption of Securities to be redeemed at the election of
the Company shall be given by the Company or, at the Company's request, by the
Trustee in the name and at the expense of the Company.

SECTION 1206.  Deposit of Redemption Price.

         Prior to any Redemption Date, the Company shall deposit with the
Trustee or with a Paying Agent (or, if the Company is acting as its own Paying
Agent, segregate and hold in trust as provided in Section 1003) an amount of
money sufficient to pay the Redemption Price of, and (except if the Redemption
Date shall be an Interest Payment Date) accrued interest on, all the Securities
which are to be redeemed on that date.

SECTION 1207.  Securities Payable on Redemption Date.

         Notice of redemption having been given as aforesaid, the Securities so
to be redeemed shall, on the Redemption Date, become due and payable at the
Redemption Price therein specified, and from and after such date (unless the
Company shall default in the payment of the Redemption Price and accrued
interest) such Securities shall cease to bear interest.  Upon surrender of any
such Security for redemption in accordance with said notice, such Security
shall be paid by the Company at the Redemption Price, together with accrued
interest to the Redemption Date; provided, however, that installments of
interest whose Stated Maturity is on or prior to the Redemption Date shall be
payable to the Holders of such Securities, or one or more Predecessor
Securities, registered as such at the close of business on the relevant Record
Dates according to their terms and the provisions of Section 307.

         If any Security called for redemption shall not be so paid upon
surrender thereof for redemption, the principal shall, until paid, bear
interest from the Redemption Date at the rate borne by the Security.

SECTION 1208.  Securities Redeemed in Part.

         Any Security which is to be redeemed only in part shall be surrendered
at a place of payment therefor (with, if the Company or the Trustee so
requires, due endorsement by, or a written instrument of transfer in form
satisfactory to the Company and the Trustee duly executed by, the Holder
thereof or his attorney duly authorized in writing), and the Company shall
execute, and the Trustee shall authenticate and deliver to the Holder of such
Security without service charge, a new Security or Securities, of any
authorized denomination as requested by such Holder, in aggregate principal
amount equal to and in exchange for the unredeemed portion of the principal of
the Security so surrendered.  The Company may not redeem fewer than all the
Outstanding Securities unless all accrued and unpaid interest (including
Additional Interest) has been paid on such Securities.

         This instrument may be executed in any number of counterparts, each of
which so executed shall be deemed to be an original, but all such counterparts
shall together constitute but one and the same instrument.





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<PAGE>   57
         IN WITNESS WHEREOF, the parties hereto have caused this Indenture to
be duly executed, all as of the day and year first above written.

                                        ENRON CORP., as Issuer
                                        
                                        
                                        By: /s/ William D. Gathmann
                                           ------------------------
                                            William D. Gathmann
                                            Vice President and Treasurer
                                        
                                        THE CHASE MANHATTAN BANK, as Trustee
                                        
                                        
                                        By: /s/ Ronald Halleran
                                           ---------------------
                                            Ronald Halleran
                                            Second Vice President
                                        
                                        



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