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                                                                   EXHIBIT 10.2





                                 August 30, 2000





David Carpi
53 Fremont St.
Somerset, NJ  08873

         Re:      Offer of Employment

Dear David:

         Enchira Biotechnology Corporation (the "Company") is pleased to offer
you the position of Vice President-Business Development on the terms provided
herein. You will report directly to and work closely with the President and
Chief Executive Officer of the Company. The purpose of this letter is to ensure
our mutual understanding and agreement on the details of your employment, which
are as follows:

EXECUTIVE POSITION & BASE SALARY

As Vice President-Business Development, you will be responsible for the
Company's strategic alliances, license agreements, collaborations, business
development and such other duties as may be assigned to you by me. You will be
entitled to an annual base salary of $170,000, paid in accordance with the
Company's normal payroll practices. The Compensation Committee of the Board of
Directors will review your base salary on an annual basis, and may authorize
merit increases in its sole discretion. You will be eligible for bonuses in the
discretion of the Board.

RELOCATION

         The Company will pay the reasonable, direct costs necessary to move
you, your family and your household goods from New Jersey to The Woodlands
area; however, we would ask that you coordinate such move with my office in
order to minimize such expenses. The Company will also pay the costs of
temporary housing and commuting expenses for you from New Jersey until 60 days
following the arbitrator's decision in the arbitration proceeding currently
pending between the Company and Maxygen (the "Targeted Relocation Date" or 60
days following the end of the New Jersey school year if necessary), provided
that all such arrangements are mutually agreeable, and will reimburse you for
usual costs incurred in selling your home in New Jersey. In addition, we will
pay for two house-hunting trips for you and your family to The Woodlands area.
All amounts paid in connection with your relocation will be grossed up for any
applicable taxes due thereon.


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EQUITY

         Upon joining the Company, you will receive an option to purchase
100,000 shares of the Company's Common Stock under the Company's Stock Option
Plan, subject to formal approval by the Board of Directors. This option will
entitle you to purchase the specified number of shares at a purchase price
which is equal to the fair market value of the Common Stock on the date your
employment commences and will contain vesting provisions as follows:

         -        25,000 shares vest as a bonus on closing of a mutually
                  agreeable strategic alliance with a biopharmaceutical company
                  within 12 months of employment; in the event that a strategic
                  alliance was not completed with a biopharmaceutical company in
                  the first 12 months of employment but is completed after 12
                  months of employment but prior to the expiration of 18 months,
                  then 25% of the 25,000 shares shall vest on completion of the
                  strategic alliance, and the remaining 75% thereof shall vest
                  on a monthly basis over a three year period of continued
                  employment thereafter.
         -        18,750 shares vest on the completion of 12 months of
                  employment with the Company, provided relocation has occurred
                  by this date.
         -        56,250 shares vest monthly over the following 36 months of
                  employment commencing on the completion of the first year of
                  employment provided relocation has occurred prior to the
                  Targeted Relocation Date.

         All shares vest in entirety upon a change of control.

EMPLOYEE BENEFITS AND VACATION

         You will be entitled to participate in all Company benefit programs in
effect from time to time on the same basis as other employees. Information
regarding such benefit programs will be sent to you under separate cover.
Please note that such policies and benefits may be changed by the Company from
time to time, subject to applicable laws.

SEVERANCE PAY

         In the event that your employment is terminated by the Company at any
time after the date hereof, except for "cause" as defined below, the Company
will continue to pay your then current salary and benefits for a period of nine
months following such termination. Such compensation will be contingent upon
your signing a waiver of rights releasing the Company from any and all further
liability or responsibility. The Company shall have no obligation to pay salary
or benefits in the event you terminate your employment or in the event the
Company terminates your employment for "Cause."

         "Cause" shall include your repeated failure, neglect or refusal, to
perform your duties and responsibilities, dishonesty affecting the Company,
excessive use of alcohol or use of illegal drugs, conviction of a felony or of
any crime involving moral turpitude, fraud or misrepresentation, or the
commission of any willful or intentional act which could reasonably be expected
to materially injure the reputation, business or business relationships of the
Company.



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SECRECY AGREEMENT

         Consistent with Company policy, you will be required to execute the
Company's standard Confidentiality and Non-Competition Agreement prior to
commencement of employment. Such non-compete agreement shall provide that you
may not, for a three year period after termination of your employment for any
reason, be employed by or otherwise associated with a direct competitor of the
Company which is engaged in directed evolution technologies for the development
of gene-based products, such as Maxygen, Diversa, or Applied Molecular
Evolution, to name a few. A copy of such agreement will be sent to you under
separate cover.

         This offer is subject to your accepting this offer by August 31, 2000,
and starting employment by September 18, 2000, to completion of our final
reference checks, and to satisfactory completion of a pre-employment physical
examination at the Company's cost. A list of physicians in your area is
included in the enclosed benefit information.

         David, it was clear during your visit that we share a great deal of
enthusiasm and high expectations for the Company's future. We believe that you
can make a significant contribution to the success of the Company and are eager
to have you join us. Please call if there is any other information or
assistance we can provide. We look forward to hearing from you and to seeing
you on September 18, 2000.

                                   Sincerely,



                                   Peter P. Policastro
                                   President and CEO

         Except as provided above, this letter does not create an employment
contract and each party is free to terminate this relationship at any time.
Please indicate your acceptance of this offer which will remain in effect until
August 31, 2000, by signing and returning the enclosed copy.


Date:
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                                   David Carpi











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