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                                                                    EXHIBIT 4.35


                                                     I.D. Control #_______
                                                     License #___________

                                    DEBENTURE
                                *****************
$3,000,000.00 (the "Original Principal Amount")
9/1/2010 (the "Maturity Date")
PMC Investment Corporation (the "Company")
18111 Preston Road Suite 600, Dallas, Texas 75252
     (Street)                 (City) (State) (Zip)

Part I  --  PERIOD SPECIFIC TERMS

         A.       Applicable for the Scheduled Interim Period (and New Interim
                  Periods, as applicable)

Interest rate per annum for the Scheduled Interim Period: 7.19800%

Annual Charge applicable to the Scheduled Interim Period: 1% per annum

Date of Issuance: 7/11/2000

Scheduled Pooling Date: September 27, 2000

Scheduled Interim Period: from and including the Date of Issuance to but
excluding the Scheduled Pooling date.

THE FOLLOWING ITALICIZED TERMS WILL APPLY IF THE INTERIM PERIOD IS EXTENDED BY
SBA:

<TABLE>
<S>                                         <C>      <C>      <C>        <C>  <C>        <C>
New Interest rate(s) per annum              (a)        %      (b)         %   (c)         %
New Annual Charge per annum                 (a)       1 %     (b)        1 %  (c)        1 %
New Pooling Date                            (a)               (b)             (c)
New Interim Period(s): from and including:  (a)               (b)             (c)
                         To but excluding:  (a)               (b)             (c)
</TABLE>

The Company, for value received, promises to pay to the Chase Manhattan Bank, as
Custodian (the "Custodian") for the U.S. Small Business Administration ("SBA")
and SBIC Funding Corporation (the "Funding Corporation"), pursuant to the
Custody and Administration Agreement (the "Custody Agreement") dated as of April
27, 1998 among the SBA, the Funding Corporation, the Federal Home Loan Bank of
Chicago, as Interim Funding Provider (the "Interim Funding Provider"), and the
Custodian: (i) interest on the Original Principal Amount listed above at the
applicable rate per annum listed above, and (ii) an Annual Charge on the
Original Principal Amount listed above at the applicable rate per annum listed
above, each at such location as SBA, as guarantor of this





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Debenture, may direct and each at the related rate per annum identified for the
Scheduled Interim Period (and each New Interim Period, if any). This Debenture
will bear interest for, and the Annual Charge will apply to, the Scheduled
Interim Period (and each New Interim Period, if any) at the rate(s) and for the
applicable period(s) indicated above, to be paid in arrears by 1:00 p.m. (New
York City time) on the Business Day prior to the Scheduled Pooling Date (and
each New Pooling Date, if any) listed above. As used throughout this Debenture,
"Business Day" means any date other than: (i) a Saturday or Sunday; (ii) a legal
holiday in Washington, D.C.; and (iii) a day on which banking institutions in
New York City are authorized or obligated by law or executive order to be
closed. Interest on this Debenture and the Annual Charge for the Scheduled
Interim Period (and each New Interim Period, if any) will each be computed on
the basis of the actual number of days in the applicable Interest Period divided
by 360. The Company may not prepay this Debenture, in whole or in part, during
the Scheduled Interim Period or any New Interim Period.

         B.       THIS SECTION B. IS EFFECTIVE ONLY AFTER (I) THE SCHEDULED
                  INTERIM PERIOD AND ANY NEW INTERIM PERIOD(S) EXPIRE AND (II)
                  THE CUSTODIAN RECEIVES THIS DEBENTURE FOR POOLING

The Company, for value received, promises to pay to the order of The Chase
Manhattan Bank, acting as Trustee (the "Trustee") under that certain Amended and
Restated Trust Agreement dated as of February 1, 1997, as the same may be
amended from time to time, by and among the Trustee, the SBA and SBIC Funding
Corporation, and as the Holder hereof, interest semiannually on March 1st and
September 1st (the "Payment Dates") of each year, at such location as SBA, as
guarantor of this Debenture, may direct at the rate of 7.452% per annum (the
"Stated Interest Rate"), and to pay a 1% per annum fee to SBA on each Payment
Date, each calculated on the basis of a year of 365 days, for the actual number
of days elapsed (including the first day but excluding the last day), on the
principal sum from the last day of the Interim Period until payment of such
principal sum has been made or duly provided for. The Company shall deposit all
payments with respect to this Debenture not later than 12:00 noon (New York City
time) on the applicable Payment Date or the next Business Day if the Payment
Date is not a Business Day, all as directed by SBA.

The Company may elect to prepay this Debenture, in whole and not in part, on any
Payment Date, in the manner and at the price as next described. The prepayment
price (the "Prepayment Price") must be an amount equal to the outstanding
principal balance of this Debenture, plus interest accrued and unpaid thereon to
the Payment Date selected for prepayment, plus a prepayment premium (the
"Prepayment Premium"). The Prepayment Premium amount is calculated as a
declining percentage (the "Applicable Percentage") multiplied by the Original
Principal Amount of this Debenture in accordance with the following table:

<TABLE>
<CAPTION>
                  Consecutive Payment Dates          Applicable Percentages
<S>                                                  <C>
                  1st or 2nd                                         5%
                  3rd or 4th                                         4%
                  5th  or 6th                                        3%
                  7th  or 8th                                        2%
                  9th or (10th - If not also Maturity Date)          1%
</TABLE>



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No Prepayment Premium is required to repay this Debenture on its Maturity Date.
No Prepayment Premium is required when the prepayment occurs on a Payment Date
that is on or after the 11th consecutive Payment Date of this Debenture, if this
Debenture has a 20 consecutive Payment Date term.

The amount of the Prepayment Price must be sent to SBA or such agent as SBA may
direct, by wire payment in immediately available funds, not less than three
Business Days prior to the regular Payment Date. Until the Company is notified
otherwise in writing by SBA, any Prepayment Price must be paid to the account
maintained by the Trustee, entitled the SBA Prepayment Subaccount and must
include an identification of the Company by name and SBA-assigned license
number, the loan number appearing on the face of this Debenture, and such other
information as SBA or its agent may specify.

II. - GENERAL TERMS

For value received, the Company promises to pay to the order of the Trustee the
Original Principal Amount on the Maturity Date at such location as SBA, as
guarantor of this Debenture, may direct.

This Debenture is issued by the Company and guaranteed by SBA, pursuant and
subject to Section 303 of the Small Business Investment act of 1958, as amended
(the "Act") (15 U.S.C. Section 683). This Debenture is subject to all of the
regulations promulgated under the Act, as amended from time to time, provided,
however, that 13 C.F.R. Sections 107.1810 and 107.1830 through 107.1850 as in
effect on the date of this Debenture are incorporated in this Debenture as if
fully set forth. If this Debenture is accelerated, then the Company promises to
pay an amount equal to the outstanding principal balance of this Debenture, plus
interest accrued and unpaid on such balance to but excluding the next Payment
Date following such acceleration.

This Debenture is deemed issued in the District of Columbia as of the day,
month, and year first stated above. The terms and conditions of this Debenture
must be construed in accordance with, and its validity and enforcement governed
by, federal law.

The warranties, representations, or certification made to SBA on any SBA Form
1022 or any application letter of the Company for an SBA commitment related to
this Debenture, and any document submitted in connection with the issuance of
this Debenture, are incorporated in this Debenture as if fully set forth.

Should any provision of this Debenture or any of the documents incorporated by
reference in this Debenture be declared illegal or unenforceable by a court of
competent jurisdiction, the remaining provisions will remain in full force and
effect and this Debenture must be construed as if such provisions were not
contained in this Debenture.

All notices to the Company which are required or may be given under this
Debenture shall be sufficient in all respects if sent to the above-noted address
of the Company. For




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the purposes of this Debenture, the Company may change this address only upon
written approval of SBA.

COMPANY ORGANIZED AS CORPORATON

IN WITNESS WHEREOF, the Company has caused this debenture to be signed by its
duly authorized officer and its corporate seal to be hereunto affixed and
attested by its Secretary or Assistant Secretary as of the date of issuance
stated above.

CORPORATE SEAL

                                         PMC Investment Corporation
                                         By: /s/ Andrew S. Rosemore
                                            ---------------------------------
                                         Andrew S. Rosemore, President
                                         ------------------------------------
                                         (Typed Name and Title)
ATTEST:
       /s/ Lance B. Rosemore
------------------------------
Secretary