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                                                                    EXHIBIT 4.43

                                                                  EXECUTION COPY

                           TRANSTEXAS GAS CORPORATION

                                  $200,000,000

                        15% Senior Secured Notes Due 2005

                          REGISTRATION RIGHTS AGREEMENT

                                                           Dated: March 15, 2000


         TransTexas Gas Corporation, a Delaware corporation (the "Company"),
proposes, subject to the terms and conditions stated in the Second Amended,
Modified and Restated Plan of Reorganization dated January 25, 2000 and pursuant
to the Order dated February 7, 2000 of the United States Bankruptcy Court for
the Southern District of Texas (the "Plan"), to issue to the TEC Bondholders, as
defined in the Plan (the "Initial Holders"), $200,000,000 principal amount of
15% Senior Secured Notes Due 2005 (the "Notes"). The Notes will be issued
pursuant to an Indenture dated as of the date hereof (the "Indenture"), by and
between the Company, as issuer, and Firstar Bank, N.A., as Trustee. The Company
hereby agrees as follows:

         1. Shelf Registration. The Company shall take the following actions:

         (a) The Company will at its cost, within seventy-five (75) days after
     the effective date of the Plan (the "Effective Date"), file with the
     Securities and Exchange Commission (the "Commission") and have declared
     effective as soon as practicable thereafter, a registration statement (the
     "Shelf Registration Statement") on an appropriate form under the Securities
     Act of 1933, as amended (the "Securities Act"), relating to the offer and
     sale of Transfer Restricted Notes (as defined in Section 7 below) by the
     Holders thereof from time to time in accordance with Rule 415 under the
     Securities Act; provided, however, that no Holder (other than the Initial
     Holders) shall be entitled to have the Notes held by it covered by such
     Shelf Registration Statement unless such Holder agrees in writing to be
     bound by all the provisions of this Agreement applicable to such Holder.

         (b) The Company shall keep the Shelf Registration Statement
     continuously effective in order to permit the prospectus included therein
     to be lawfully delivered by the Holders of the relevant Notes until five
     years from the Issue Date (as defined in the Indenture) or for such shorter
     period that will terminate when all the Notes covered by the Shelf
     Registration Statement have been sold pursuant thereto.

         (c) Notwithstanding any other provisions of this Agreement to the
     contrary, the Company shall cause the Shelf Registration Statement, and the
     related prospectus and any amendment or supplement thereto, as of the
     effective date of the Shelf Registration Statement, or amendment or
     supplement thereto, (i) to comply in all material respects



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     with the applicable requirements of the Securities Act and the rules and
     regulations of the Commission and (ii) not to contain any untrue statement
     of a material fact or omit to state a material fact required to be stated
     therein or necessary in order to make the statements therein, in light of
     the circumstances under which they were made, not misleading.

         2. Registration Procedures. In connection with the registration
pursuant to Rule 415 under the Securities Act contemplated by Section 1 hereof
(the "Shelf Registration"), the following provisions shall apply:

         (a) At least three (3) days prior to the filing thereof with the
     Commission, the Company shall furnish to the Initial Holders a copy of the
     proposed form of the Shelf Registration Statement and each amendment
     thereto and each supplement, if any, to the prospectus included therein,
     and shall in its reasonable judgment reflect in each such document, when so
     filed with the Commission, such comments as such Initial Holders may
     reasonably propose.

         (b) The Company shall give written notice to the Holders (which notice
     pursuant to clauses (ii) - (v) hereof shall be accompanied by an
     instruction to suspend the use of the prospectus until the requisite
     changes have been made):

             (i) when the Shelf Registration Statement or any amendment thereto
         has been filed with the Commission and when the Shelf Registration
         Statement or any post-effective amendment thereto has become effective;

             (ii) of any request by the Commission for amendments or supplements
         to the Shelf Registration Statement or the prospectus included therein
         or for additional information;

             (iii) of the issuance by the Commission of any stop order
         suspending the effectiveness of the Shelf Registration Statement or the
         initiation of any proceedings for that purpose;

             (iv) of the receipt by the Company or its legal counsel of any
         notification with respect to the suspension of the qualification of the
         Notes for sale in any jurisdiction or the initiation or threatening of
         any proceeding for such purpose; and

             (v) of the happening of any event that requires the Company to make
         changes in the Shelf Registration Statement or the prospectus in order
         that the Shelf Registration Statement or the prospectus does not
         contain an untrue statement of a material fact nor omit to state a
         material fact required to be stated therein or necessary to make the
         statements therein not misleading.

         (c) The Company shall make every reasonable effort to obtain the
     withdrawal at the earliest possible time of any order suspending the
     effectiveness of the Shelf Registration Statement.



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         (d) The Company shall furnish to each Holder included within the
     coverage of the Shelf Registration, without charge, at least one copy of
     the Shelf Registration Statement and any post-effective amendment thereto,
     including financial statements and schedules, and, if the Holder so
     requests in writing, all exhibits thereto (including those, if any,
     incorporated by reference).

         (e) The Company shall deliver to each Holder included within the
     coverage of the Shelf Registration, without charge, as many copies of the
     prospectus (including each preliminary prospectus) included in the Shelf
     Registration Statement and any amendment or supplement thereto as such
     person may reasonably request. The Company consents, subject to the
     provisions of this Agreement, to the use of the prospectus or any amendment
     or supplement thereto included in the Shelf Registration Statement by each
     of the selling Holders in connection with the offering and sale of the
     Notes covered by such prospectus or any such amendment or supplement.

         (f) Prior to any public offering of the Notes pursuant to the Shelf
     Registration, the Company shall register or qualify or cooperate with the
     Holders of Notes included therein and their respective counsel in
     connection with the registration or qualification of the Notes for offer
     and sale under the securities or "blue sky" laws of such states of the
     United States as any Holder reasonably requests in writing and do any and
     all other acts or things necessary or advisable to enable the offer and
     sale in such jurisdictions of the Notes covered by the Shelf Registration
     Statement; provided, however, that the Company shall not be required to (i)
     qualify generally to do business in any jurisdiction where it is not then
     so qualified or (ii) take any action which would subject it to general
     service of process or to taxation in any jurisdiction where it is not then
     so subject.

         (g) The Company shall cooperate with the Holders to facilitate the
     timely preparation and delivery of certificates representing the Notes to
     be sold pursuant to the Shelf Registration Statement free of any
     restrictive legends and in such denominations and registered in such names
     as such Holders may request a reasonable period of time prior to sales of
     the Notes pursuant to the Shelf Registration Statement.

         (h) Upon the occurrence of any event contemplated by paragraphs (ii)
     through (v) of Section 2(b) above during the period for which the Company
     is required to maintain an effective Shelf Registration Statement, the
     Company shall promptly prepare and file a post-effective amendment to the
     Shelf Registration Statement or a supplement to the related prospectus and
     any other required document so that, as thereafter delivered to Holders,
     the prospectus will not contain an untrue statement of a material fact or
     omit to state any material fact required to be stated therein or necessary
     to make the statements therein, in light of the circumstances under which
     they were made, not misleading. If the Company notifies the Holders in
     accordance with paragraphs (ii) through (v) of Section 2(b) above to
     suspend the use of the prospectus until the requisite changes to the
     prospectus have been made, then the Holders shall suspend use of such
     prospectus, and the period of effectiveness of the Shelf Registration
     Statement provided for in Section 1(b) above shall be extended by the
     number of days from and including the date of the



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     giving of such notice to and including the date when the Holders shall have
     received such amended or supplemented prospectus pursuant to this Section
     2(h).

         (i) The Company will comply with all rules and regulations of the
     Commission to the extent and so long as they are applicable to the Shelf
     Registration and will make generally available to its security holders (or
     otherwise provide in accordance with Section 11(a) of the Securities Act)
     an earnings statement satisfying the provisions of Section 11(a) of the
     Securities Act, no later than 45 days after the end of a 12-month period
     (or 90 days, if such period is a fiscal year) beginning with the first
     month of the Company's first fiscal quarter commencing after the effective
     date of the Shelf Registration Statement, which statement shall cover such
     12-month period.

         (j) The Company may require each Holder of Notes to be sold pursuant to
     the Shelf Registration Statement to furnish to the Company such information
     regarding such Holder and the distribution of the Notes as the Company may
     from time to time reasonably require for inclusion in the Shelf
     Registration Statement, and the Company may exclude from such Shelf
     Registration Statement the Notes of any Holder that unreasonably fails to
     furnish such information within a reasonable time after receiving such
     request.

         (k) The Company shall enter into such customary agreements (including,
     if requested, an underwriting agreement in customary form) and take all
     such other action, if any, as any Holder shall reasonably request in order
     to facilitate the disposition of the Notes pursuant to the Shelf
     Registration in an underwritten offering or otherwise.

         (l) The Company shall: (i) make reasonably available for inspection by
     the Holders, any underwriter participating in any disposition pursuant to
     the Shelf Registration Statement and any attorney, accountant or other
     agent retained by the Holders or any such underwriter, all relevant
     financial and other records, pertinent corporate documents and properties
     of the Company and (ii) cause the Company's officers, directors, employees,
     accountants and auditors to supply all relevant information reasonably
     requested by the Holders or any such underwriter, attorney, accountant or
     agent in connection with the Shelf Registration Statement, in each case as
     shall be reasonably necessary, in the judgment of such Holder or any such
     underwriter, attorney, accountant or agent referred to in this paragraph,
     to conduct a reasonable investigation within the meaning of Section 11 of
     the Securities Act; provided, however, that the foregoing inspection and
     information gathering shall be coordinated by the Initial Holders and on
     behalf of the other parties by counsel designated by and on behalf of such
     other parties as described in Section 3 hereof.

         Until the Shelf Registration Statement is filed with the Commission,
     the Company may require each Holder to agree to keep confidential any
     non-public information, relating to the Company, received by such Holder in
     accordance with this Section 2(l) and not disclose such information (other
     than to an affiliate or prospective purchaser who agrees to respect the
     confidentiality provisions of this Section 2(l)); provided that each Holder
     shall be released from its confidentiality obligations hereunder to the
     extent necessary to permit such Holder to trade its Notes in compliance
     with the securities laws



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     if the Company breaches its obligations to timely file the Shelf
     Registration Statement and each Holder shall be relieved of its
     confidentiality obligations hereunder if the release of such information is
     required by law or necessary to respond to inquiries of regulatory
     authorities; provided, however, that no Holder shall be relieved of its
     confidentiality obligation with respect to any such information otherwise
     permitted to be released pursuant to this Section 2 (l) that is not
     material to the Company. The foregoing requirement shall exclude
     information which (i) is or becomes generally available to the public other
     than as a result of disclosure by the Holder or the Holder's
     Representatives, or (ii) becomes available to the Holder or any of the
     Holder's Representatives on a non-confidential basis from a source other
     than the Company or its affiliates or Representatives, provided that
     neither the Holder or any of the Holder's Representatives is aware that
     such source is under an obligation (whether contractual, legal or
     fiduciary) to the Company or its affiliates or Representatives to keep such
     information confidential. For purposes hereof, the "Representatives" of any
     entity means such entity's directors, officers, employees, legal and
     financial advisors, accounts and other agents and representatives.

         (m) The Company, if requested by any Holder of the Notes covered
     thereby, shall cause (i) its counsel to deliver an opinion and updates
     thereof relating to the Notes in customary form addressed to the selling
     Holders of the applicable Notes or the managing underwriters, if any,
     thereof and dated, in the case of the initial opinion, the effective date
     of such Shelf Registration Statement, it being agreed that the matters to
     be covered by such opinion shall include, without limitation, the due
     incorporation and good standing of the Company and its subsidiaries; the
     due authorization, execution and delivery of the relevant agreement of the
     type referred to in Section 3(k) hereof; the due authorization, execution,
     authentication and issuance, and the validity and enforceability, of the
     Notes; the absence of material legal or governmental proceedings involving
     the Company; the absence of governmental approvals required to be obtained
     in connection with the Shelf Registration Statement, the offering and sale
     of the Notes or any agreement of the type referred to in Section 3(k)
     hereof; the compliance as to form of such Shelf Registration Statement and
     any documents incorporated by reference therein and of the Indenture with
     the requirements of the Securities Act and the Trust Indenture Act,
     respectively; and, as of the date of the opinion and as of the effective
     date of the Shelf Registration Statement or most recent post effective
     amendment thereto, as the case may be, the absence from such Shelf
     Registration Statement and the prospectus included therein, as then amended
     or supplemented, and from any documents incorporated by reference therein,
     of an untrue statement of a material fact or the omission to state therein
     a material fact required to be stated therein or necessary to make the
     statements therein not misleading (in the case of any such documents, in
     the light of the circumstances existing at the time that such documents
     were filed with the Commission under the Securities Exchange Act of 1934,
     as amended (the "Exchange Act"), all subject to customary assumptions and
     qualifications and otherwise in form and content customary for similar
     opinions; (ii) its officers to execute and deliver all customary documents
     and certificates and updates thereof requested by the selling Holders of
     the applicable Notes or any underwriters of the applicable Notes; and (iii)
     its independent public accountants to provide to the selling Holders of the
     applicable Notes and any underwriter therefor a comfort letter in customary
     form and covering matters of the type customarily covered in



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     comfort letters in connection with primary underwritten offerings, subject
     to receipt of appropriate documentation as contemplated, and only if
     permitted, by Statement of Auditing Standards No. 72.

         (n) The Company shall use commercially reasonable efforts to cause the
     Notes covered by the Shelf Registration Statement to be rated (or to have
     any existing rating confirmed) with the appropriate rating agencies, if so
     requested by the managing underwriters or by the Holders of a majority in
     aggregate principal amount of the Notes covered by the Shelf Registration
     Statement.

         (o) The Company and the Subsidiary Guarantors shall use their best
     efforts to take all other steps necessary to effect the registration of the
     Notes covered by the Shelf Registration Statement contemplated hereby.

         3. Registration Expenses. The Company shall bear all fees and expenses
incurred in connection with the performance of its obligations under Sections 1
and 2 hereof, whether or not the Shelf Registration is filed or becomes
effective, and, shall bear or reimburse the Holders of the Notes covered
thereby, for the reasonable fees and disbursements of one firm of counsel
designated by the Holders of a majority in principal amount of the Notes covered
thereby to act as counsel for the Holders in connection therewith.

         4. Indemnification.

         (a) The Company shall indemnify and hold harmless each Holder and each
     person, if any, who controls such Holder within the meaning of the Exchange
     Act (each such Holder and each such controlling person being referred to
     collectively as the "Indemnified Parties") from and against any losses,
     claims, damages or liabilities, joint or several, or any actions in respect
     thereof (including, but not limited to, any losses, claims, damages,
     liabilities or actions relating to purchases and sales of the Notes) to
     which each Indemnified Party may become subject under the Securities Act,
     the Exchange Act or otherwise, insofar as such losses, claims, damages,
     liabilities or actions arise out of or are based upon any untrue statement
     or alleged untrue statement of a material fact contained in the Shelf
     Registration Statement or any prospectus included therein or in any
     amendment or supplement thereto, or arise out of, or are based upon, the
     omission or alleged omission to state therein a material fact required to
     be stated therein or necessary to make the statements therein not
     misleading. The Company shall reimburse, as incurred, each Indemnified
     Party for any legal or other expenses reasonably incurred by it in
     connection with investigating or defending any such loss, claim, damage,
     liability or action in respect thereof. The Company shall not, however, be
     liable in any such case to the extent that such loss, claim, damage,
     liability or action arises out of or is based upon any untrue statement or
     alleged untrue statement or omission or alleged omission made in the Shelf
     Registration Statement or any prospectus included therein or in any
     amendment or supplement thereto or in any preliminary prospectus relating
     to the Shelf Registration in reliance upon and in conformity with written
     information pertaining to such Holder and furnished to the Company by or on
     behalf of such Holder specifically for inclusion therein. The Company shall
     also indemnify underwriters, selling brokers, dealer managers and similar
     securities industry professionals participating in the distribution (in



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     each case as described in the Shelf Registration Statement), their officers
     and directors and each person who controls such persons within the meaning
     of the Securities Act or the Exchange Act to the same extent as provided
     above with respect to the indemnification of the Holders if requested by
     such Holders.

         (b) Each Holder, severally and not jointly, will indemnify and hold
     harmless the Company and each person, if any, who controls the Company
     within the meaning of the Securities Act or the Exchange Act from and
     against any losses, claims, damages, liabilities or actions in respect
     thereof to which the Company or any such controlling person may become
     subject under the Securities Act, the Exchange Act or otherwise, insofar as
     such losses, claims, damages, liabilities or actions arise out of or are
     based upon any untrue statement or alleged untrue statement of a material
     fact contained in the Shelf Registration Statement or any prospectus
     included therein or in any amendment or supplement thereto or in any
     preliminary prospectus relating to the Shelf Registration, or arise out of
     or are based upon the omission or alleged omission to state therein a
     material fact necessary to make the statements therein not misleading, but
     in each case only to the extent that the untrue statement or alleged untrue
     statement or omission or alleged omission was made in reliance upon and in
     conformity with written information pertaining to such Holder and furnished
     to the Company by or on behalf of such Holder specifically for inclusion
     therein; and, subject to the limitation set forth immediately preceding
     this clause, shall reimburse, as incurred, the Company for any legal or
     other expenses reasonably incurred by the Company or any controlling person
     in connection with investigating or defending any loss, claim, damage,
     liability or action in respect thereof. This indemnity agreement will be in
     addition to any liability which such Holder may otherwise have to the
     Company and any of their controlling persons.

         (c) Promptly after receipt by an Indemnified Party under this Section 4
     of notice of the commencement of any action or proceeding (including a
     governmental investigation), such Indemnified Party will, if a claim in
     respect thereof is to be made against any person (the "Indemnifying Party")
     under this Section 4, notify the Indemnifying Party of the commencement
     thereof; but the omission so to notify the Indemnifying Party will not, in
     any event, relieve the Indemnifying Party from any obligations to any
     Indemnified Party including the indemnification obligation provided in
     paragraph (a) or (b) above. In case any such action is brought against any
     Indemnified Party, and it notifies the Indemnifying Party of the
     commencement thereof, the Indemnifying Party will be entitled to
     participate therein and, to the extent that it may wish, jointly with any
     other Indemnifying Party similarly notified, to assume the defense thereof,
     with counsel reasonably satisfactory to such Indemnified Party (who shall
     not, except with the consent of the Indemnified Party, be counsel to the
     Indemnifying Party), and after notice from the Indemnifying Party to such
     Indemnified Party of its election to assume the defense thereof, the
     Indemnifying Party will not be liable to such Indemnified Party under this
     Section 4 for any legal or other expenses, other than reasonable costs of
     investigation, subsequently incurred by such Indemnified Party in
     connection with the defense thereof. No Indemnifying Party shall, without
     the prior written consent of the Indemnified Party, effect any settlement
     of any pending or threatened action in respect of which any Indemnified
     Party is or could have been a party and indemnity could have been sought
     hereunder by such Indemnified Party unless such settlement includes an



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     unconditional release of such Indemnified Party from all liability on any
     claims that are the subject matter of such action.

         (d) If the indemnification provided for in this Section 4 is
     unavailable or insufficient to hold harmless an Indemnified Party, then
     each Indemnified Party shall contribute to the amount paid or payable to
     such Indemnifying Party as a result of the losses, claims, damages or
     liabilities referred to in this Section 4 an amount or additional amount,
     as the case may be, in such proportion as is appropriate to reflect the
     relative fault of the Indemnifying Party or parties on the one hand and the
     Indemnified Party on the other in connection with the statements or
     omission which resulted in such loses, claims, demands or liabilities as
     well as any other relevant equitable considerations. The relative fault
     shall be determined by reference to, among other things, whether the untrue
     or alleged untrue statement of a material fact or the omission or alleged
     omission to state a material fact relates to information supplied by the
     Indemnifying Party or parties on the one hand or the Indemnified Party on
     the other and the parties' relative intent, knowledge, access to
     information and opportunity to correct or prevent such untrue statement or
     omission. The amount paid to an Indemnified Party as a result of the
     losses, claims, damages or liabilities referred to in the first sentence of
     this Section 4 shall be deemed to include any legal or other expenses
     reasonably incurred by such Indemnified Party in connection with
     investigating or defending any action or claim which is the subject of this
     Section 4. No person guilty of fraudulent misrepresentation within the
     meaning of Section 11(f) of the Securities Act shall be entitled to
     contribution from any person who was not guilty of such fraudulent
     misrepresentation.

         (e) The agreements contained in this Section 4 shall survive the sale
     of the Notes pursuant to the Shelf Registration Statement and shall remain
     in full force and effect, regardless of any termination or cancellation of
     this Agreement or any investigation made by or on behalf of any indemnified
     party.

         5. Rules 144 and 144A. The Company shall use commercially reasonable
efforts to file the reports required to be filed by it under the Securities Act
and the Exchange Act in a timely manner and, if at any time the Company is not
required to file such reports, it will, upon the request of any Holder of
Transfer Restricted Notes (as defined below), make publicly available other
information so long as necessary to permit sales of their Notes pursuant to
Rules 144 and 144A. The Company covenants that it will take such further action
as any Holder of Transfer Restricted Notes may reasonably request, all to the
extent required from time to time to enable such Holder to sell Transfer
Restricted Notes without registration under the Securities Act within the
limitation of the exemptions provided by Rules 144 and 144A (including the
requirements of Rule 144A (d) (4)). The Company will provide a copy of this
Agreement to prospective purchasers of Transfer Restricted Notes identified to
the Company upon request. Upon the request of any Holder of Transfer Restricted
Notes, the Company shall deliver to such Holder a written statement as to
whether the Company has complied with such requirements.

         6. Underwritten Registrations. If any of the Transfer Restricted Notes
covered by the Shelf Registration are to be sold in an underwritten offering,
the managing underwriters will be selected by the Holders of a majority in
aggregate principal amount of such Transfer Restricted Notes to be included in
such offering.



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         No person may participate in any underwritten registration hereunder
unless such person (i) agrees to sell such person's Transfer Restricted Notes on
the basis reasonably provided in any underwriting arrangements approved by the
persons entitled hereunder to approve such arrangements and (ii) completes and
executes all questionnaires, powers of attorney, indemnities, underwriting
agreements and other documents reasonably required under the terms of such
underwriting arrangements.

         7. Definitions:

         "Holder" means the Initial Holders and any person or entity to whom
Transfer Restricted Notes are validly transferred by an Initial Holder or a
Holder pursuant to an exemption from the registration requirements of the
Securities Act other than Rule 144 promulgated under the Securities Act.

         "Transfer Restricted Notes" means each Note until (i) the date on which
such Note has been effectively registered under the Securities Act and disposed
of in accordance with the Shelf Registration Statement or (ii) the date on which
such Note is distributed to the public pursuant to Rule 144 under the Securities
Act.

         8. Miscellaneous.

         (a) Amendments and Waivers. The provisions of this Agreement may not be
     amended, modified or supplemented, and waivers or consents to departures
     from the provisions hereof may not be given, except by the Company and with
     the written consent of the Holders of 75% in aggregate principal amount of
     then outstanding Notes affected by such amendment, modification,
     supplement, waiver or consent.

         (b) Notices. All notices and other communications provided for or
     permitted hereunder shall be made in writing by hand delivery, first-class
     mail, facsimile transmission, or air courier which guarantees overnight
     delivery:

         (1) if to a Holder, at the most current address given by such Holder to
     the Company in accordance with the provisions of this Section 8(b), which
     address initially is, with respect to each Holder, the address of such
     Holder to which confirmation of the sale of such Notes to such Holder was
     first sent by the Company with copies in like manner to you as follows:

                          Cadwalader, Wickersham & Taft
                          100 Maiden Lane
                          New York, New York 10038
                          Fax No.:(212) 504-6666
                          Attention: Brian Hoffmann



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         (2) if to the Company at the Company's address as follows:

                          TransTexas Gas Corporation
                          1300 North Sam Houston Parkway East
                          Houston, Texas 77032-2949
                          Fax No.: (281) 986-8877
                          Attention: Secretary

             with a copy to:

                          Gardere & Wynne, L.L.P.
                          3000 Thanksgiving Tower
                          1601 Elm Street, Suite 3000
                          Dallas, TX  75201
                          Fax No.: (214) 999-3534
                          Attention: C. Robert Butterfield

         All such notices and communications shall be deemed to have been duly
     given: at the time delivered by hand, if personally delivered; three
     business days after being deposited in the mail, postage prepaid, if
     mailed; when receipt is acknowledged by recipient's facsimile machine
     operator, if sent by facsimile transmission; and on the day delivered, if
     sent by overnight air courier guaranteeing next day delivery.

         (c) No Inconsistent Agreements. The Company has not, as of the date
     hereof, entered into, nor shall it, on or after the date hereof, enter
     into, any agreement with respect to its Notes that is inconsistent with the
     rights granted to the Holders herein or otherwise conflicts with the
     provisions hereof.

         (d) Successors and Assigns. This Agreement shall be binding upon the
     Company and its respective successors and assigns; provided however, that
     no successor or assign may exercise any rights under this Agreement unless
     such successor or assign agrees in writing to be bound by the provisions
     hereof.

         (e) Headings. The headings in this Agreement are for convenience of
     reference only and shall not limit or otherwise affect the meaning hereof.

         (f) Governing Law. THIS AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED
     IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK WITHOUT REGARD TO
     PRINCIPLES OF CONFLICTS OF LAWS.

         (g) Severability. If any one or more of the provisions contained
     herein, or the application thereof in any circumstance, is held invalid,
     illegal or unenforceable, the validity, legality and enforceability of any
     such provision in every other respect and of the remaining provisions
     contained herein shall not be affected or impaired thereby.



<PAGE>   11


         If the foregoing is in accordance with your understanding of our
agreement, please sign and return to TransTexas a counterpart hereof, whereupon
this Agreement will become a binding agreement among the Company and the Initial
Holders in accordance with its terms.



                                       Very truly yours,



                                       TRANSTEXAS GAS CORPORATION



                                       By:
                                          --------------------------------------
                                          Name:
                                          Title:



<PAGE>   12


                                       The foregoing Registration Rights
                                       Agreement is hereby confirmed and
                                       accepted as of the date first above
                                       written.

                                       Initial Holders


                                       CREDIT SUISSE FIRST BOSTON CORPORATION



                                       By:
                                          --------------------------------------
                                          Name:
                                          Title


                                       OAKTREE CAPITAL MANAGEMENT, LLC as
                                       general partner and investment manager of
                                       certain funds and accounts it manages



                                       By:
                                          --------------------------------------
                                          Name:
                                          Title


                                       By:
                                          --------------------------------------
                                          Name:
                                          Title


                                       ANGELO GORDON & CO., L.P.



                                       By:
                                          --------------------------------------
                                          Name:
                                          Title