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                                                                    EXHIBIT 3.2

                              AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION

         CERUS CORPORATION, a corporation organized and existing under and by
virtue of the General Corporation Law of the State of Delaware, hereby certifies
as follows:

         1. The name of the corporation is Cerus Corporation.

         2. The corporation's original Certificate of Incorporation was filed
with the Secretary of State on July 31, 1996.

         3. The Amended and Restated Certificate of Incorporation of this
corporation, in the form attached hereto as Exhibit A, has been duly adopted in
accordance with the provisions of Sections 242 and 245 of the General
Corporation Law of the State of Delaware by the Board of Directors and by the
stockholders of the corporation, and prompt written notice was duly given
pursuant to Section 228 of the General Corporation Law of the State of Delaware
to those stockholders who did not approve the Amended and Restated Certificate
of Incorporation by written consent.

         4. The Amended and Restated Certificate of Incorporation so adopted
reads in full as set forth in Exhibit A attached hereto and hereby incorporated
by reference.

         IN WITNESS WHEREOF, Cerus Corporation has caused this Amended and
Restated Certificate of Incorporation to be signed by its President and Chief
Executive Officer and attested to by its Secretary this _____ day of
____________, 1996.

                                           _____________________________________
                                           STEPHEN T. ISAACS
                                           President and Chief Executive Officer

ATTEST:


_____________________________
LORI ROLL
Secretary



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                                    EXHIBIT A

                              AMENDED AND RESTATED
                          CERTIFICATE OF INCORPORATION

                                       OF

                                CERUS CORPORATION

                                       I.

         The name of this corporation is Cerus Corporation.

                                       II.

         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, and the
name of the registered agent of the corporation in the State of Delaware at such
address is the National Registered Agents, Inc.

                                      III.

         The purpose of this corporation is to engage in any lawful act or
activity for which a corporation may be organized under the General Corporation
Law of the State of Delaware.

                                       IV.

         A. This corporation is authorized to issue two classes of stock to be
designated, respectively, "Common Stock" and "Preferred Stock." The total number
of shares which the corporation is authorized to issue is fifty-five million
(55,000,000) shares. Fifty million (50,000,000) shares shall be Common Stock,
each having a par value of one-tenth of one cent ($.001). Five million
(5,000,000) shares shall be Preferred Stock, each having a par value of
one-tenth of one cent ($.001).

         The Preferred Stock may be issued from time to time in one or more
series. The Board of Directors is hereby authorized, by filing a certificate (a
"Preferred Stock Designation") pursuant to the Delaware General Corporation Law,
to fix or alter from time to time the designation, powers, preferences and
rights of the shares of each such series and the qualifications, limitations or
restrictions of any wholly unissued series of Preferred Stock, and to establish
from time to time the number of shares constituting any such series or any of
them; and to increase or decrease the number of shares of any series subsequent
to the issuance of shares of that series, but not below the number of shares of
such series then outstanding. In case the number of shares of any series shall
be decreased in accordance with the foregoing

 
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sentence, the shares constituting such decrease shall resume the status that
they had prior to the adoption of the resolution originally fixing the number of
shares of such series.

                                       V.

         For the management of the business and for the conduct of the affairs
of the Corporation, and in further definition, limitation and regulation of the
powers of the Corporation, of its directors and of its stockholders or any class
thereof, as the case may be, it is further provided that:

         A.

                  1. The management of the business and the conduct of the
affairs of the Corporation shall be vested in its Board of Directors. The number
of directors which shall constitute the whole Board of Directors shall be fixed
exclusively by one or more resolutions adopted by the Board of Directors.

                  2. Subject to the rights of the holders of any series of
Preferred Stock to elect additional directors under specified circumstances,
following the closing of the initial public offering pursuant to an effective
registration statement under the Securities Act of 1933, as amended (the "1933
Act"), covering the offer and sale of Common Stock to the public (the "Initial
Public Offering"), the directors shall be divided into three classes designated
as Class I, Class II and Class III, respectively. Directors shall be assigned to
each class in accordance with a resolution or resolutions adopted by the Board
of Directors. At the first annual meeting of stockholders following the closing
of the Initial Public Offering, the term of office of the Class I directors
shall expire and Class I directors shall be elected for a full term of three
years. At the second annual meeting of stockholders following the closing of the
Initial Public Offering, the term of office of the Class II directors shall
expire and Class II directors shall be elected for a full term of three years.
At the third annual meeting of stockholders following the closing of the Initial
Public Offering, the term of office of the Class III directors shall expire and
Class III directors shall be entered for a full-term of three years. At each
succeeding annual meeting of stockholders, directors shall be elected for a full
term of three years to succeed the directors of the class whose terms expire at
such annual meeting.

                  Notwithstanding the foregoing provisions of this Article, each
director shall serve until his successor is duly elected and qualified or until
his death, resignation or removal. No decrease in the number of directors
constituting the Board of Directors shall shorten the term of any incumbent
director.

                  3. Subject to the rights of the holders of any series of
Preferred Stock, any vacancies on the Board of Directors resulting from death,
resignation, disqualification, removal or other causes and any newly created
directorships resulting from any increase in the number of directors, shall,
unless the Board of Directors determines by resolution that any such vacancies
or newly created directorships shall be filled by the stockholders, except as
otherwise

 
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provided by law, be filled only by the affirmative vote of a majority of the
directors then in office, even though less than a quorum of the Board of
Directors, and not by the stockholders. Any director elected in accordance with
the preceding sentence shall hold office for the remainder of the full term of
the director for which the vacancy was created or occurred and until such
director's successor shall have been elected and qualified.

         B.

                  1. Subject to paragraph (h) of Section 43 of the Bylaws, the
Bylaws may be altered or amended or new Bylaws adopted by the affirmative vote
of at least sixty-six and two-thirds percent (66-2/3%) of the voting power of
all of the then-outstanding shares of voting stock of the Corporation entitled
to vote at an election of directors (the "Voting Stock"). The Board of Directors
shall also have the power to adopt, amend, or repeal Bylaws.

                  2. The directors of the Corporation need not be elected by
written ballot unless the Bylaws so provide.

                  3. No action shall be taken by the stockholders of the
Corporation except at an annual or special meeting of stockholders called in
accordance with the Bylaws and following the closing of the Initial Public
Offering no action shall be taken by the stockholders by written consent.

                  4. Advance notice of stockholder nominations for the election
of directors and of business to be brought by stockholders before any meeting of
the stockholders of the Corporation shall be given in the manner provided in the
Bylaws of the Corporation.

                                       VI.

         A. A director of the Corporation shall not be personally liable to the
Corporation or its stockholders for monetary damages for any breach of fiduciary
duty as a 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 an improper
personal benefit. If the Delaware General Corporation Law is amended after
approval by the stockholders of this Article to authorize corporate action
further eliminating or limiting the personal liability of directors, then the
liability of a director shall be eliminated or limited to the fullest extent
permitted by the Delaware General Corporation Law, as so amended.

         B. Any repeal or modification of this Article VI shall be prospective
and shall not affect the rights under this Article VI in effect at the time of
the alleged occurrence of any act or omission to act giving rise to liability or
indemnification.


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                                      VII.

         A. The Corporation reserves the right to amend, alter, change or repeal
any provision contained in this Certificate of Incorporation, in the manner now
or hereafter prescribed by statute, except as provided in paragraph B of this
Article VII, and all rights conferred upon the stockholders herein are granted
subject to this reservation.

         B. Notwithstanding any other provisions of this Certificate of
Incorporation or any provision of law which might otherwise permit a lesser vote
or no vote, but in addition to any affirmative vote of the holders of any
particular class or series of the Voting Stock required by law, this Certificate
of Incorporation or any Preferred Stock Designation, the affirmative vote of the
holders of at least sixty-six and two-thirds percent (66-2/3%) of the voting
power of all of the then-outstanding shares of the Voting Stock, voting together
as a single class, shall be required to alter, amend or repeal Articles V, VI
and VII.

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