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                                                                     Exhibit 3.1


                          CERTIFICATE OF INCORPORATION

                                       OF

                                  MITOKOR, INC.


         FIRST: The name of the corporation is MitoKor, Inc., (the
"Corporation")

         SECOND: The address of its registered office in the State of Delaware
is 1209 Orange Street in the City of Wilmington, County of New Castle. The name
of its registered agent at such address is CT Corporation.

         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 Delaware.

         FOURTH: The Corporation is authorized to issue one class of stock, to
be designated "Common Stock," with a par value of $0.001 per share. The total
number of shares of Common Stock that the Corporation shall have authority to
issue is one hundred (100).

         FIFTH: The business and affairs of the Corporation shall be managed by
or under the direction of the Corporation's board of directors (the "Board of
Directors"). In addition to the powers and authority expressly conferred upon
them by statute or by this Certificate of Incorporation or the Bylaws of the
Corporation (the "Bylaws"), the directors are hereby empowered to exercise all
such powers and do all such acts and things as may be exercised or done by the
Corporation. Election of directors need not be by written ballot, unless the
Bylaws so provide.

         SIXTH: The Board of Directors is authorized to make, adopt, amend,
alter or repeal the Bylaws. The stockholders shall also have power to make,
adopt, amend, alter or repeal the Bylaws.

         SEVENTH: The name and mailing address of the incorporator is:

                           Mark Cadigan
                           Gray Cary Ware & Freidenrich LLP
                           4365 Executive Drive, Suite 1100
                           San Diego, CA 92121-2133

         EIGHTH: To the fullest extent permitted by the Delaware General
Corporation Law, as the same exists or may hereafter be amended, a director of
the Corporation shall not be personally liable to the Corporation or its
stockholders for monetary damages for breach of fiduciary duty as a director.
Any repeal or modification of the foregoing provisions of this Article EIGHTH 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, or increase
the liability of any director of the Corporation with respect to any acts or
omissions occurring prior to, such repeal or modification.


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         THE UNDERSIGNED, being the incorporator hereinbefore named, for the
purpose of forming a corporation pursuant to the General Corporation Law of
Delaware, does make this certificate, hereby declaring and certifying that this
is my act and deed and the facts herein stated are true, and accordingly have
hereunto set my hand this 7th day of March, 2002.


                                       /s/ Mark Cadigan
                                       -----------------------------------------
                                       Mark Cadigan, Incorporator


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