Exhibit 3.8

                             AMENDED AND RESTATED
                         CERTIFICATE OF INCORPORATION
                                      OF
                                 MAXYGEN, INC.

          Maxygen, Inc., a corporation organized and existing under the laws of
the State of Delaware, hereby certifies as follows:

          1.  The name of the corporation is Maxygen, Inc.  The corporation was
originally incorporated under the same name, and the original Certificate of
Incorporation of the corporation was filed with the Secretary of State of the
State of Delaware on May 7, 1996.

          2.  Pursuant to Sections 242 and 245 of the General Corporation Law of
the State of Delaware, this Amended and Restated Certificate of Incorporation
restates and amends the provisions of the Certificate of Incorporation of the
corporation.

          3.  The Certificate of Incorporation of the corporation is hereby
amended and restated to read in its entirety as set forth in the Amended and
Restated Certificate of Incorporation attached hereto as Exhibit A.

          IN WITNESS WHEREOF, Maxygen, Inc. has caused this Amended and Restated
Certificate of Incorporation to be duly executed by its Chief Executive Officer
and attested to by its Chief Financial Officer this ____ day of __________,
______.

                                       MAXYGEN, INC.


                                       By: _____________________________________
                                           Russell J. Howard, Ph.D.
                                           President and Chief Executive Officer

ATTEST:


__________________________________
Simba Gill, Ph.D., M.B.A.
Chief Financial Officer and
Senior Vice President of Business
Development


                                   Exhibit A
                                   ---------

                             AMENDED AND RESTATED

                         CERTIFICATE OF INCORPORATION

                                      OF

                                 MAXYGEN, INC.

     FIRST.   The name of the corporation is Maxygen, Inc.
     -----

     SECOND.  The address of the registered office of the corporation in the
     ------
State of Delaware is 9 East Loockerman Street, City of Dover, County of Kent.
The name of its registered agent at such address is National Corporate Research,
Ltd.

     THIRD.   The nature of the business or purposes to be conducted or promoted
     -----
is to engage in any lawful act or activity for which corporations may be
organized under the General Corporation Law of the State of Delaware.

     FOURTH.  The total number of shares of all classes of capital stock which
     ------
the corporation shall have authority to issue is Seventy-Five Million
(75,000,000) shares, comprised of Seventy Million (70,000,000) shares of Common
Stock with a par value of $0.0001 per share (the "Common Stock") and Five
Million (5,000,000) shares of Preferred Stock with a par value of $0.0001 per
share (the "Preferred Stock").

     A description of the respective classes of stock and a statement of the
designations, preferences, voting powers (or no voting powers), relative,
participating, optional or other special rights and privileges and the
qualifications, limitations and restrictions of the Preferred Stock and Common
Stock are as follows:

     A.  PREFERRED STOCK
         ---------------

         The Preferred Stock may be issued in one or more series at such time
or times and for such consideration or considerations as the board of directors
may determine.  Each series shall be so designated as to distinguish the shares
thereof from the shares of all other series and classes.  Except as may be
expressly provided in this Amended and Restated Certificate of Incorporation,
including any certificate of designations for a series of Preferred Stock,
different series of Preferred Stock shall not be construed to constitute
different classes of shares for the purpose of voting by classes.


          The board of directors is expressly authorized, subject to the
limitations prescribed by law and the provisions of this Amended and Restated
Certificate of Incorporation, to provide for the issuance of all or any shares
of the Preferred Stock, in one or more series, each with such designations,
preferences, voting powers (or no voting powers), relative, participating,
optional or other special rights and privileges and such qualifications,
limitations or restrictions thereof as shall be stated in the resolution or
resolutions adopted by the board of directors to create such series, and a
certificate of designations setting forth a copy of said resolution or
resolutions shall be filed in accordance with the General Corporation Law of the
State of Delaware.  The authority of the board of directors with respect to each
such series shall include without limitation of the foregoing the right to
specify the number of shares of each such series and to authorize an increase or
decrease in such number of shares and the right to provide that the shares of
each such series may be: (i) subject to redemption at such time or times and at
such price or prices; (ii) entitled to receive dividends (which may be
cumulative or non-cumulative) at such rates, on such conditions, and at such
times, and payable in preference to, or in such relation to, the dividends
payable on any other class or classes or any other series; (iii) entitled to
such rights upon the dissolution of, or upon any distribution of the assets of,
the corporation; (iv) convertible into, or exchangeable for, shares of any other
class or classes of stock, or of any other series of the same or any other class
or classes of stock of the corporation at such price or prices or at such rates
of exchange and with such adjustments, if any; (v) entitled to the benefit of
such limitations, if any, on the issuance of additional shares of such series or
shares of any other series of Preferred Stock; or (vi) entitled to such other
preferences, powers, qualifications, rights and privileges, all as the board of
directors may deem advisable and as are not inconsistent with law and the
provisions of this Amended and Restated Certificate of Incorporation.  The
number of authorized shares of Preferred Stock may be increased or decreased
(but not below the number of shares thereof then outstanding) by the affirmative
vote of the holders of a majority of the Common Stock, without a vote of the
holders of the Preferred Stock, or of any series thereof, unless a vote of such
holder is required pursuant to the terms of any Preferred Stock designation.

     B.   COMMON STOCK
          ------------

          1.  Relative Rights of Preferred Stock and Common Stock.  All
              ---------------------------------------------------
preferences, voting powers, relative, participating, optional or other special
rights and privileges, and qualifications, limitations, or restrictions of the
Common Stock are expressly made subject and subordinate to those that may be
fixed with respect to any shares of the Preferred Stock.

          2.  Voting Rights.  Except as otherwise required by law or this
              -------------
Amended and Restated Certificate of Incorporation, each holder of Common Stock
shall have one vote in respect of each share of stock held by such holder of
record on the books

                                       2


of the corporation for the election of directors and on all matters submitted to
a vote of stockholders of the corporation; provided, however, that, except as
                                           --------  -------
otherwise required by law, holders of Common Stock shall not be entitled to vote
on any amendment to this Amended and Restated Certificate of Incorporation
(including any certificate of designations relating to any series of Preferred
Stock) that relates solely to the terms of one or more outstanding series of
Preferred Stock if the holders of such affected series are entitled, either
separately or together as a class with the holders of one or more other such
series, to vote thereon pursuant to this Amended and Restated Certificate of
Incorporation (including any certificate of designations relating to any series
of Preferred Stock).

          3.  Cumulative Voting.  Holders of stock of any class or series of the
              -----------------
corporation shall not be entitled to cumulate their votes for the election of
directors or any other matter submitted to a vote of the stockholders, unless
such cumulative voting is required pursuant to Sections 2115 or 301.5 of the
California General Corporation Law, in which event each such holder shall be
entitled to as many votes as shall equal the number of votes which (except for
this provision as to cumulative voting) such holder would be entitled to cast
for the election of directors with respect to such holder's shares of stock
multiplied by the number of directors to be elected by such holder, and the
holder may cast all of such votes for a single director or may distribute them
among the number of directors to be voted for, or for any two or more of them as
such holder may see fit, so long as the name of the candidate for director shall
have been placed in nomination prior to the voting and the stockholder, or any
other holder of the same class or series of stock, has given notice at the
meeting prior to the voting of the intention to cumulate votes.

          4.  Dividends.  Subject to the preferential rights of the Preferred
              ---------
Stock, the holders of shares of Common Stock shall be entitled to receive, when
and if declared by the board of directors, out of the assets of the corporation
which are by law available therefor, dividends payable either in cash, in
property or in shares of capital stock.

          5.  Dissolution, Liquidation or Winding Up.  In the event of any
              --------------------------------------
dissolution, liquidation or winding up of the affairs of the corporation, after
distribution in full of the preferential amounts, if any, to be distributed to
the holders of shares of Preferred Stock, holders of Common Stock shall be
entitled, unless otherwise provided by law or this Amended and Restated
Certificate of Incorporation, including any certificate of designations for a
series of Preferred Stock, to receive all of the remaining assets of the
corporation of whatever kind available for distribution to stockholders ratably
in proportion to the number of shares of Common Stock held by them respectively.

     FIFTH.  The corporation is to have perpetual existence.
     -----

     SIXTH.  In furtherance and not in limitation of the powers conferred by the
     -----
laws of the State of Delaware:

                                       3


     A.   The board of directors of the corporation is expressly authorized:

          (i)   To make, alter or repeal the By-Laws of the corporation.

          (ii)  To authorize and cause to be executed mortgages and liens upon
the real and personal property of the corporation.

          (iii) To set apart out of any of the funds of the corporation
available for dividends a reserve or reserves for any proper purpose and to
abolish any such reserve in the manner in which it was created.

          (iv)  By a majority of the whole board, to designate one or more
committees, each committee to consist of one or more of the directors of the
corporation. The board may designate one or more directors as alternate members
of any committee, who may replace any absent or disqualified member of any
committee. The By-Laws may provide that in the absence or disqualification of a
member of a committee, the member or members thereof present at any meeting and
not disqualified from voting, whether or not such member or members constitute a
quorum, may unanimously appoint another member of the board of directors to act
at the meeting in the place of any such absent or disqualified member. Any such
committee, to the extent provided in the resolution of the board of directors,
or in the By-Laws of the corporation, shall have and may exercise all the powers
and authority of the board of directors in the management of the business and
affairs of the corporation, and may authorize the seal of the corporation to be
affixed to all papers which may require it; but no such committee shall have the
power or authority in reference to amending the Amended and Restated Certificate
of Incorporation (except that a committee may, to the extent authorized in the
resolution or resolutions providing for the issuance of shares of stock adopted
by the board of directors as provided in Section 151(a) of the General
Corporation Law of the State of Delaware, fix any of the preferences or rights
of such shares relating to dividends, redemption, dissolution, any distribution
of assets of the corporation or the conversion into, or the exchange of such
shares for, shares of any other class or classes or any other series of the same
or any other class or classes of stock of the corporation), adopting an
agreement of merger or consolidation under Sections 251 or 252 of the General
Corporation Law of the State of Delaware, recommending to the stockholders the
sale, lease or exchange, of all or substantially all of the corporation's
property and assets, recommending to the stockholders a dissolution of the
corporation or a revocation of a dissolution, or amending the By-Laws of the
corporation; and, unless the resolution or By-Laws expressly so provided, no
such committee shall have the power or authority to declare a dividend, to
authorize the issuance of stock, or to adopt a certificate of ownership and
merger pursuant to Section 253 of the General Corporation Law of the State of
Delaware.

                                       4


          (v)   When and as authorized by the stockholders in accordance with
statute, to sell, lease or exchange all or substantially all of the property and
assets of the corporation, including its good will and its corporate franchises,
upon such terms and conditions and for such consideration, which may consist in
whole or in part of money or property, including shares of stock in, and/or
other securities of, any other corporation or corporations, as its board of
directors shall deem expedient and for the best interests of the corporation.

     B.   Elections of directors need not be by written ballot unless the By-
Laws of the corporation shall so provide.

     C.   The books of the corporation may be kept at such place within or
without the State of Delaware as the By-Laws of the corporation may provide or
as may be designated from time to time by the board of directors of the
corporation.

     D.   Special meetings of stockholders of the corporation may be called only
by the board of directors acting pursuant to a resolution adopted by a majority
of the Whole Board. For purposes of this Amended and Restated Certificate of
Incorporation, the term "Whole Board" shall mean the total number of authorized
directors whether or not there exist any vacancies in previously authorized
directorships.

     SEVENTH.  Whenever a compromise or arrangement is proposed between this
     -------
corporation and its creditors or any class of them and/or between this
corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this corporation or of any creditor or stockholder thereof or on the
application of any receiver or receivers appointed for this corporation under
the provisions of Section 291 of Title 8 of the Delaware Code or on the
application of trustees in dissolution or of any receiver or receivers appointed
for this corporation under the provisions of Section 279 of Title 8 of the
Delaware Code, order a meeting of the creditors or classes of creditors, and/or
of the stockholders or classes of stockholders of this corporation, as the case
may be, to be summoned in such manner as the said court directs.  If a majority
in number representing three-fourths in value of the creditors or class of
creditors, and/or of the stockholders or class of stockholders of this
corporation, as the case may be, agree to any compromise or arrangement and to
any reorganization of this corporation as a consequence of such compromise or
arrangement, the said compromise or arrangement and the said reorganization
shall, if sanctioned by the court to which the said application has been made,
be binding on all the creditors or class of creditors, and/or on all the
stockholders or class of stockholders, of this corporation, as the case may be,
and also on this corporation.

     EIGHTH.  A director of this corporation shall not be personally liable to
     ------
the corporation or its stockholders for monetary damages for breach of fiduciary
duty as a

                                       5


director, except for liability (i) for any breach of the director's duty of
loyalty to the corporation or its stockholders, (ii) for acts or omissions not
in good faith or which involve intentional misconduct or a knowing violation of
law, (iii) under Section 174 of the Delaware General Corporation Law, or (iv)
for any transaction from which the director derived any improper personal
benefit. If the Delaware General Corporation Law is amended hereafter to
authorize corporate action further eliminating or limiting the personal
liability of directors, then the liability of a director of the corporation
shall be eliminated or limited to the fullest extent permitted by the Delaware
General Corporation Law, as so amended.

          Any repeal or modification of the foregoing paragraph by the
stockholders of the corporation shall not adversely affect any right or
protection of a director of the corporation existing at the time of repeal or
modification.

     NINTH.
     -----

     A.  RIGHT TO INDEMNIFICATION
         ------------------------

         Each person who was or is made a party or is threatened to be made a
party to or is involved in any action, suit or proceeding, whether civil,
criminal, administrative or investigative ("proceeding"), by reason of the fact
that he or she or a person of whom he or she is the legal representative, is or
was a director or officer, employee or agent of the corporation or is or was
serving at the request of the corporation as a director or officer, employee or
agent of another corporation, or of a partnership, joint venture, trust or other
enterprise, including service with respect to employee benefit plans, whether
the basis of such proceeding is alleged action in an official capacity as a
director, officer, employee or agent or in any other capacity while serving as a
director, officer, employee or agent, shall be indemnified and held harmless by
the corporation to the fullest extent authorized by the Delaware General
Corporation Law, as the same exists or may hereafter be amended, (but, in the
case of such amendment, only to the extent that such amendment permits the
corporation to provide broader indemnification rights than said Law permitted
the corporation to provide prior to such amendment) against all expenses,
liability and loss (including attorneys' fees, judgments, fines, ERISA excise
taxes or penalties and amounts paid or to be paid in settlement) reasonably
incurred or suffered by such person in connection therewith and such
indemnification shall continue as to a person who has ceased to be a director,
officer, employee or agent and shall insure to the benefit of his or her heirs,
executors and administrators; provided, however,  that the corporation shall
                              --------  -------
indemnify any such person seeking indemnity in connection with an action, suit
or proceeding (or part thereof) initiated by such person only if such action,
suit or proceeding (or part thereof) was authorized by the board of directors of
the corporation.  Such right shall be a contract right and shall include the
right to be paid by the corporation expenses incurred in defending any such
proceeding in advance of its final

                                       6


disposition; provided, however, that the payment of such expenses incurred by a
             --------  -------
director or officer of the corporation in his or her capacity as a director or
officer and not in any other capacity in which service was or is rendered by
such person while a director or officer including (without limitation, service
to an employee benefit plan) in advance of the final disposition of such
proceeding, shall be made only upon delivery to the corporation of an
undertaking, by or on behalf of such director or officer, to repay all amounts
so advanced if it should be determined ultimately that such director or officer
is not entitled to be indemnified under this Section or otherwise.

     B.  RIGHT OF CLAIMANT TO BRING SUIT
         -------------------------------

         If a claim under Paragraph A of Article NINTH is not paid in full by
the corporation within ninety (90) days after a written claim has been received
by the corporation, the claimant may at any time thereafter bring suit against
the corporation to recover the unpaid amount of the claim and, if successful in
whole or in part, the claimant shall be entitled to be paid also the expense of
prosecuting such claim. It shall be a defense to any such action (other than an
action brought to enforce a claim for expenses incurred in defending any
proceeding in advance of its final disposition where the required undertaking,
if any, has been tendered to this corporation) that the claimant has not met the
standards of conduct which make it permissible under the Delaware General
Corporation Law for the corporation to indemnify the claimant for the amount
claimed, but the burden of proving such a defense shall be on the corporation.
Neither the failure of the corporation (including its board of directors,
independent legal counsel, or its stockholders) to have made a determination
prior to the commencement of such action that indemnification of the claimant is
proper in the circumstances because he or she has met the applicable standard of
conduct set forth in the Delaware General Corporation Law, nor an actual
determination by the corporation (including its board of directors, independent
legal counsel, or its stockholders) that the claimant has not met such
applicable standard of conduct, shall be a defense to the action or create a
presumption that claimant has not met the applicable standard of conduct.

     C.  NON-EXCLUSIVITY OF RIGHTS
         -------------------------

         The rights conferred on any person by Paragraphs A and B of Article
NINTH shall not be exclusive of any other right which such persons may have or
hereafter acquire under any statute, provision of the Amended and Restated
Certificate of Incorporation, By-Law, agreement, vote of stockholders or
disinterested directors or otherwise.

     D.  INSURANCE
         ---------

         The corporation may maintain insurance, at its expense, to protect
itself and any director, officer, employee or agent of the corporation or
another corporation,

                                       7


partnership, joint venture, trust or other enterprise against, any expense,
liability or loss reasonably incurred or suffered by such person in connection
with his or her service as a director, officer, employee or agent of such
entity, whether or not the corporation would have the power to indemnify such
person against such expense, liability or loss under the Delaware General
Corporation Law.

     TENTH.  The corporation reserves the right to amend or repeal any provision
     -----
contained in this Amended and Restated Certificate of Incorporation, in the
manner now or hereafter prescribed by statute, and all rights conferred upon a
stockholder herein are granted subject to this reservation.

                                       8