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                                                                   EXHIBIT 10.31

                              EMPLOYMENT AGREEMENT

     THIS EMPLOYMENT AGREEMENT (this "Agreement") is entered into as of February
l7, 2000 between PROTEIN POLYMER TECHNOLOGIES, INC., a Delaware corporation
(the "Company"), and JOHN FLOWERS (the "Employee").

                                     RECITAL

     The Company desires to continue to employ the Employee, and the Employee
desires to be so employed by the Company, on the terms and subject to the
conditions set forth in this Agreement. This Agreement supersedes that certain
employment agreement between the Company and the Employee dated November 1, 1996
(the "Prior Agreement").

                                    AGREEMENT

     NOW, THEREFORE, in consideration of the premises and the mutual promises
set forth in this Agreement, the Company and the Employee hereby agree as
follows:

     1.   Employment.

          (a) Subject to the terms and conditions contained herein, the Company
hereby agrees to employ the Employee, and the Employee accepts such employment,
from the date hereof until the earlier of (i) December 31, 2002 or (ii) the date
such employment is terminated pursuant to Section 4 of this Agreement. During
the Employee's employment under this Agreement, the Employee shall perform such
duties for the Company as may from time to time be assigned to the Employee by
Board of Directors of the Company (the "Board") or the President of the Company
(the "Designated Officer"). The Employee shall have the title of Vice President,
Planning and Operations and Director, Intellectual Property, or such other title
or titles, if any, as from time to time may be assigned to the Employee by the
Board.

          (b) The Employee will devote his entire business time, energy,
attention and skill to the services of the Company and its affiliates and to the
promotion of their interests. So long as the Employee is employed by the
Company, the Employee shall not, without the written consent of the Company:

                  (i) engage in any other activity for compensation, profit or
other pecuniary advantage, whether received during or after the term of this
Agreement;

                  (ii) render or perform services of a business, professional,
or commercial nature other than to or for the Company, either alone or as an
employee, consultant, director, officer, or partner of another business entity,
whether or not for compensation, and whether or not such activity, occupation or
endeavor is similar to, competitive with, or adverse to the business or welfare
of the Company; or
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                  (iii) invest in or become a shareholder of another corporation
or other entity; provided, that the Employee's investment solely as a
shareholder in another corporation shall not be prohibited hereby so long as
such investment is not in excess of one percent (1%) of any class of shares that
are traded on a national securities exchange.

          (c) Prior to or concurrently with the execution of this Agreement, the
Employee has executed an Employee Proprietary information, Trade Secret and
Confidentiality Agreement (the "Confidentiality Agreement").

     2. Location of Employment. The Employee's principal place of employment
shall be at the executive offices of the Company located at 10655 Sorrento
Valley Road, San Diego, California 92121 or, as may be requested by the Board,
at any other office of the Company or any of its affiliates currently or
hereinafter located in San Diego County; provided, that at the direction of the
Board or the Designated Officer, the Employee may from time to time be required
to travel to various domestic and foreign locations.

     3. Compensation.

          (a) In exchange for full performance of the Employee's obligations and
duties under this Agreement, the Company shall pay the Employee an annual base
salary (the "Base Salary") equal to $125,000, payable in monthly installments in
accordance with the Company's standard payroll practices. In any month in which
the Employee shall be employed for less than the entire number of days in such
month, the compensation payable under this Section 3(a) shall be prorated on the
basis of the number of days during which the Employee was actually employed
divided by the number of days in such month.

          (b) The Base Salary is a gross amount, and the Company shall be
required to withhold from such amount deductions with respect to Federal, state
and local taxes, FICA, unemployment compensation taxes and similar taxes,
assessments or withholding requirements.

          (c) During the Employee's employment under this Agreement, the
Employee shall also be reimbursed by the Company for reasonable business
expenses actually incurred or paid by the Employee, consistent with the policies
established by the Board, in rendering to the Company the services provided for
in this Agreement, upon presentation of expense statements or such other
supporting information as is consistent with the policies of the Company.

          (d) The Employee shall be entitled to 20 business days vacation for
each full year of employment under this Agreement, which vacation time will
accrue in accordance with the vacation policy of the Company.

          (e) The Employee shall be entitled to participate in all benefit plans
(including deferred compensation plans and any medical, dental or life insurance
plans) which shall

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be available from time to time to the domestic management employees of the
Company generally, except to the extent such participation in any plan would, in
the opinion of the Designated Officer, alter the intended tax treatment of such
plan; provided, however, that the Employee shall have no right under this
Agreement to participate in any stock option, stock purchase or other plan
relating to shares of capital stock of the Company or its affiliates. The
Employee acknowledges and agrees that the Board may in its discretion terminate
at any time or modify from time to time any such benefit plans.

          (f) Other than as expressly set forth in this Section 3 or
Sections 4(f) and 4(g) below, the Employee shall not receive any other
compensation or benefits except to the extent provided by the Board.

     4. Termination.

          (a) The employment of the Employee under this Agreement may be
terminated by the Company immediately upon giving the Employee notice if (i) the
Board determines that the Employee is unable to discharge his essential job
duties by reason of illness or injury or (ii) the Employee has been unable to
discharge his essential job duties by reason of illness or injury for either (A)
a period of two consecutive months or (B) twelve weeks in any twelve-month
period.

          (b) The employment of the Employee under this Agreement shall
terminate on the date of the Employee's death.

          (c) The employment of the Employee under this Agreement may be
terminated by the Company upon written notice from the Board that, in the
opinion of the Board, the Employee has (i) refused or failed (after reasonable
notice that such refusal or failure would result in termination of the
Employee's employment) to perform, to the satisfaction of the Designated Officer
or the Board, any duties assigned to the Employee by the Designated Officer or
the Board, (ii) committed a breach of the terms of this Agreement or any other
legal obligation to the Company, (iii) failed to perform any of the Employee's
obligations under the Confidentiality Agreement, (iv) demonstrated negligence or
willful misconduct in the execution of the Employee's assigned duties, (v) been
convicted of or pleaded nolo contendere to a felony or other serious crime, (vi)
                        ---- ----------
repeatedly and intemperately used alcohol or drugs, (vii) engaged in business
practices which, in the opinion of the Board, are unethical or reflect adversely
on the Company, (viii) misappropriated assets of the Company or (ix) been
repeatedly absent from work during normal business hours for reasons other than
disability.

          (d) The employment of the Employee under this Agreement shall
terminate upon receipt by the Board of a written notice of resignation signed by
the Employee or, if no notice is given, on the date on which the Employee
voluntarily terminates his or her employment relationship with the Company.

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          (e) In addition to the circumstances described in subsections (a),
(b), (c) and (d) above, the Company may terminate the Employee's employment for
any reason or no reason and with or without cause or prior notice. The Employee
understands that, subject to subsections (f)(iii) and (g) below, he is an
at-will employee and may be terminated by the Company without cause or prior
notice pursuant to this subsection (e) notwithstanding any other provision
contained in this Agreement. This at-will relationship will remain in effect
during the term of this Agreement and so long thereafter provided that the
Employee remains employed by the Company, unless such at-will employment
relationship is modified by a specific, express written agreement signed by the
Company.

          (f) If the Employee's employment is terminated pursuant to this
Section 4 or for any other reason, the Employee shall not be entitled to any
compensation or benefits from the Company, under Section 3 of this Agreement or
otherwise, except for the following:

                  (i) Base Salary and vacation pay accrued, and reasonable
business expenses incurred, under Section 3 of this Agreement through the date
of such termination;

                  (ii) such benefits, if any, as may be required to be provided
by the Company under the Comprehensive Omnibus Budget Reconciliation Act
(COBRA);

                  and

                  (iii) if the Employee's employment is terminated pursuant to
subsection (e) above, the Company shall continue to pay to the Employee the Base
Salary then in effect at intervals in accordance with the Company's standard
payroll practice until the earlier of (A) six months following such termination
or (B) the termination date set forth in Section l(a)(i) of this Agreement.

          (g) Employee may terminate his employment hereunder for "Good Reason"
(as hereinafter defined).

                  (i) For purposes of this Agreement, "Good Reason" shall mean a
termination of Employee's employment by Employee within 90 days after the
occurrence of any of the following after a "Change in Control" (as hereinafter
defined): (i) a reduction in Employee's Base Salary then in effect; (ii) a
material reduction in Employee's positions, duties and responsibilities from
those described in Section l(a) of this Agreement; or (iii) the failure of the
Company to obtain the assumption of this Agreement by any successor to the
extent required pursuant to Section 10(a) of this Agreement.

                  (ii) For purposes of this Agreement, the term "Change in
Control" shall mean the occurrence of any of the following events with respect
to the Company:

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                         (A) All or substantially all of the assets of the
Company are sold or transferred to another corporation or entity; or

                         (B) The Company is sold, transferred, merged,
consolidated, ventured or reorganized into or with another corporation or
entity, with the result that upon conclusion of the transaction less than a
majority of the outstanding securities entitled to vote generally in the
election of directors or other capital interests of the acquiring corporation or
entity are owned, directly or indirectly, by the shareholders of the Company
immediately prior to the sale, transfer, merger, consolidation, venture or
reorganization; or

                         (C) There is a report filed on Schedule 13D or Schedule
14D-1 (or any successor schedule, form or report), each as promulgated pursuant
to the Securities Exchange Act of 1934, as amended (the "Exchange Act"),
disclosing that any person (as the term "person" is used in Section 13(d)(3) or
Section 14(d)(2) of the Exchange Act) has become the beneficial owner (as the
term "beneficial owner" is defined under Rule 13d-3 or any successor rule or
regulation promulgated under the Exchange Act) of securities representing more
than 50% of the combined voting power of the then-outstanding voting securities
of the Company; or

                         (D) The Company shall file a report or proxy statement
with the Securities and Exchange Commission pursuant to the Exchange Act
disclosing in response to Item 1 of Form 8-K thereunder or Item 14 of Schedule
14A thereunder (or any successor schedule, form or report or item therein) that
a change in control of the Company has or may have occurred or will or may occur
in the future pursuant to any then-existing contract or transaction; or

                         (E) The individuals who, at the beginning of any period
of two consecutive calendar years, constituted members of the Board cease for
any reason to constitute at least a majority thereof unless the nomination for
election by the Company's stockholders of each new director of the Company was
approved by a vote of at least two-thirds of the directors of the Company still
in office who were Directors of the Company at the beginning of any such period.

                  (iii) Notwithstanding the foregoing, a termination shall not
be treated as a termination for Good Reason (i) if Employee shall have
specifically consented in writing to the occurrence of the event giving rise to
the claim of termination for Good Reason or (ii) unless Employee, within 30 days
after receiving written notice from the Company specifying in reasonable detail
the occurrence of one of such events, shall have delivered a written notice to
the Company stating that he intends to terminate his employment for Good Reason
and specifying the factual basis for such termination and such event, if capable
of being cured, shall not have been cured within 30 days of the receipt by the
Company of such notice.

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                  (iv) If Employee shall terminate his employment for Good
Reason, the Company shall pay Employee (or, in the event of his death, his
devisee, legatee or, if there is none, his estate) a lump-sum amount equal to
the highest level of Employee's annual Base Salary in effect on the date of the
Change in Control, multiplied by a factor of 2.0. Employee will also be entitled
to any vested benefits under any employee benefit plans.

     5. Employee's Representations.

          (a) The Employee represents that he has full authority to enter into
this Agreement and that he is free to enter into this Agreement and not under
any contractual restraint which would prohibit the Employee from satisfactorily
performing his duties to the Company under this Agreement.

          (b) The Employee hereby agrees to indemnify, and hold harmless the
Company, its officers, directors and stockholders from and against any losses,
liabilities, damages or costs (including reasonable attorney's fees) arising out
of a breach, or claimed breach, of any of the representations, warranties and
covenants of the Employee set forth in this Agreement.

          (c) The Employee acknowledges that he is free to seek advice from
independent counsel with respect to this Agreement. The Employee has either
obtained such advice or, after carefully reviewing this Agreement, has decided
to forego such advice. The Employee is not relying on any representation or
advice from the Company or any of its officers, directors, attorneys or other
representatives regarding this Agreement, its content or effect.

     6. Arbitration. Any controversy or claim arising out of or relating to this
Agreement or any breach hereof or the Employee's employment by the Company or
termination thereof, shall be settled by arbitration by one arbitrator in
accordance with the rules of the American Arbitration Association, and judgment
upon such award rendered by the arbitrator may be entered in any court having
jurisdiction thereof. The arbitration shall be held in the City of San Diego or
such other place as may be agreed upon at the time by the parties to the
arbitration.

     7. Equitable Relief. The Employee acknowledges that the Company is relying
for its protection upon the existence and validity of the provisions of this
Agreement, that the services to be rendered by the Employee are of a special,
unique and extraordinary character, and that irreparable injury will result to
the Company from any violation or continuing violation of the provisions of this
Agreement for which damages may not be an adequate remedy. Accordingly, the
Employee hereby agrees that in addition to the remedies available to the Company
by law or under this Agreement, the Company shall be entitled to obtain such
equitable relief as may be permitted by law in a court of competent jurisdiction
including, without limitation, injunctive relief from any violation or
continuing violation by the Employee of any term or provision of this Agreement.

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     8. Governing Law. This Agreement shall be governed by and construed and
enforced in accordance with the internal substantive laws (and not the laws of
conflicts) of the State of California.

     9. Entire Agreement. This Agreement constitutes the whole agreement of the
parties hereto in reference to any employment of the Employee by the Company and
in reference to any of the matters or things herein provided for or hereinabove
discussed or mentioned in reference to such employment; all prior agreements,
promises, representations and understandings relative thereto (including,
without limitation, the Prior Agreement) being herein merged.

     10. Assignability.

          (a) In the event the Company shall merge or consolidate with any
other corporation, partnership or business entity, or all or substantially all
of the Company's business or assets shall be transferred in any manner to any
other corporation, partnership or business entity, then such successor to the
Company shall thereupon succeed to, and be subject to, all rights, interests,
duties and obligations of, and shall thereafter be deemed for all purposes
hereof to be, the "Company" under this Agreement. This Agreement shall inure to
the benefit of and be enforceable by Employee's personal or legal
representatives, executors, administrators, successors, heirs, distributees,
devisees and legatees. If Employee should die, any amounts payable to him
hereunder shall be paid in accordance with the terms of this Agreement to
Employee's devisee, legatee, or other designee or, if there be no such designee,
to his estate.

          (b) This Agreement is personal in nature and the Employee shall not,
except as set forth in subsection (a) hereof, without the written consent of the
Company, assign or transfer this Agreement or any rights or obligations
hereunder

          (c) Except as set forth in subsection (a) above, nothing expressed or
implied in this Agreement is intended or shall be construed to confer upon or
give to any person, other than the parties to this Agreement, any right, remedy
or claim under or by reason of this Agreement or of any term, covenant or
condition of this Agreement.

     11. Amendments; Waivers. This Agreement may be amended, modified,
superseded, canceled, renewed or extended and the terms or covenants of this
Agreement may be waived only by a written instrument executed by the parties to
this Agreement or, in the case of a waiver, by the party waiving compliance. Any
such written instrument must be approved by the Board to be effective as against
the Company. The failure of any party at any time or times to require
performance of any provision of this Agreement shall in no manner affect the
right at a later time to enforce the same. No waiver by any party of the breach
of any term or provision contained in this Agreement, whether by conduct or
otherwise, in any one or more instances, shall be deemed to be, or construed as,
a further or continuing waiver of any such breach, or a waiver of the breach of
any other term or covenant contained in this Agreement.

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     12. Notice. Ail notices, requests or consents required or permitted under
this Agreement shall be made in writing ad shall be given to the other parties
by personal delivery, overnight air courier (with receipt signature) or
facsimile transmission (with "answerback" confirmation of transmission), sent to
such parties' addresses or telecopy numbers as are set forth below such parties'
signatures to this Agreement, or such other addresses or telecopy numbers of
which the parties have given notice pursuant to this Section 12. Each such
notice, request or consent shall be deemed effective upon the date of actual
receipt, receipt signature or confirmation of transmission, as applicable.

     13. Severability. Any provision of this Agreement that is prohibited or
unenforceable in any jurisdiction shall, as to such jurisdiction, be ineffective
to the extent of such prohibition or unenforceability without invalidating the
remaining provisions hereof, and any such prohibition or unenforceability in any
jurisdiction shall not invalidate or render unenforceable such provision in any
other jurisdiction

     14. Survival. The representations and agreements of the Employee set forth
in Sections 5, 6 and 7 of this Agreement shall survive the expiration or
termination of this Agreement (irrespective of the reason for such expiration of
termination).

     15. Attorney's Fees. If any party to this Agreement seeks to enforce his or
its rights under this Agreement, the prevailing party or parties shall be
entitled to recover reasonable fees, costs and expenses incurred in connection
therewith including, without limitation, the fees, costs and expenses of
attorneys, accountants and experts, whether or not litigation is instituted, and
including such fees, costs and expenses of appeals.

                            [Signature page follows]

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     IN WITNESS WHEREOF, the parties to this Agreement have executed this
Employment Agreement as of the date first above written.



                              PROTEIN POLYMER TECHNOLOGIES, INC.

                              By    /s/ J. THOMAS PARMETER
                                 ----------------------------------
                                    Its  President

                              Address for Notices:

                              10655 Sorrento Valley Road
                              First Floor
                              San Diego, California 92121
                              Attention: J. Thomas Parmeter
                              Telecopy: (619) 558-6477


                              /s/ JOHN FLOWERS
                              -------------------------------------
                              John Flowers

                              Address for notices:


                              1005 Santa Queta
                              Solana Beach, CA 92075

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