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                                                                     Exhibit 3.3







                                     BYLAWS

                                       OF

                                  MITOKOR, INC.





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                                     BYLAWS
                                       OF
                                  MITOKOR, INC.


                                    ARTICLE I
                                  STOCKHOLDERS

         Section 1.1 ANNUAL MEETING. An annual meeting of the stockholders of
MitoKor, Inc., (the "Corporation"), for the election of directors and for the
transaction of such other business as may properly come before the meeting,
shall be held at such place, on such date, and at such time as the Corporation's
board of directors (the "Board of Directors") shall each year fix, which date
shall be within thirteen months subsequent to the later of the date of
incorporation or the last annual meeting of stockholders.

         Section 1.2 SPECIAL MEETINGS. Special meetings of the stockholders, for
any purpose or purposes prescribed in the notice of the meeting, may be called
by (1) the Board of Directors pursuant to a resolution adopted by a majority of
the total number of authorized directors (whether or not there exist any
vacancies in previously authorized directorships at the time any such resolution
is presented to the Board of Directors for adoption), (2) the Chief Executive
Officer or (3) the holders of shares entitled to cast not less than ten percent
(10%) of the votes at the meeting, and shall be held at such place, on such
date, and at such time as they shall fix. Business transacted at special
meetings shall be confined to the purpose or purposes stated in the notice.

         Section 1.3 NOTICE OF MEETINGS. Written notice of the place, date, and
time of all meetings of the stockholders shall be given not less than ten (10)
nor more than sixty (60) days before the date on which the meeting is to be
held, to each stockholder entitled to vote at such meeting, except as otherwise
provided herein or required by law (meaning, here and hereinafter, as required
from time to time by the Delaware General Corporation Law or the Certificate of
Incorporation of the Corporation).

         When a meeting is adjourned to another place, date or time, written
notice need not be given of the adjourned meeting if the place, date and time
thereof are announced at the meeting at which the adjournment is taken;
PROVIDED, HOWEVER, that if the date of any adjourned meeting is more than thirty
(30) days after the date for which the meeting was originally noticed, or if a
new record date is fixed for the adjourned meeting, written notice of the place,
date, and time of the adjourned meeting shall be given in conformity herewith.
At any adjourned meeting, any business may be transacted which might have been
transacted at the original meeting.

         Section 1.4 QUORUM. At any meeting of the stockholders, the holders of
a majority of all of the shares of the stock entitled to vote at the meeting,
present in person or by proxy, shall constitute a quorum for all purposes,
unless or except to the extent that the presence of a larger number may be
required by law or by the Corporation's Certificate of Incorporation (the
"Certificate of Incorporation") or the bylaws of this Corporation (these
"Bylaws").


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         If a quorum shall fail to attend any meeting, the chairman of the
meeting or the holders of a majority of the shares of stock entitled to vote who
are present, in person or by proxy, may adjourn the meeting to another place,
date, or time.

         If a notice of any adjourned special meeting of stockholders is sent to
all stockholders entitled to vote thereat, stating that it will be held with
those present constituting a quorum, then except as otherwise required by law,
those present at such adjourned meeting shall constitute a quorum, and all
matters shall be determined by a majority of the votes cast at such meeting.

         Section 1.5 ORGANIZATION. Such person as the Board of Directors may
have designated or, in the absence of such a person, the chief executive officer
of the Corporation or, in his absence, such person as may be chosen by the
holders of a majority of the shares entitled to vote who are present, in person
or by proxy, shall call to order any meeting of the stockholders and act as
chairman of the meeting. In the absence of the Secretary of the Corporation, the
secretary of the meeting shall be such person as the chairman appoints.

         Section 1.6 CONDUCT OF BUSINESS. The chairman of any meeting of
stockholders shall determine the order of business and the procedure at the
meeting, including such regulation of the manner of voting and the conduct of
discussion as seem to him in order.

         Section 1.7 PROXIES AND VOTING. At any meeting of the stockholders,
every stockholder entitled to vote may vote in person or by proxy authorized by
an instrument in writing filed in accordance with the procedure established for
the meeting.

         Each stockholder shall have one vote for every share of stock entitled
to vote which is registered in such stockholder's name on the record date for
the meeting, except as otherwise provided herein or required by law.

         All voting, except where otherwise required by law, may be by a voice
vote; PROVIDED, HOWEVER, that upon demand therefor by a stockholder entitled to
vote or by his or her proxy, a stock vote shall be taken. Every stock vote shall
be taken by ballots, each of which shall state the name of the stockholder or
proxy voting and such other information as may be required under the procedure
established for the meeting. Every vote taken by ballots shall be counted by an
inspector or inspectors appointed by the chairman of the meeting.

         All elections shall be determined by a plurality of the votes cast, and
except as otherwise required by law or these Bylaws, all other matters shall be
determined by a majority of the votes cast.

         Section 1.8 STOCK LIST. A complete list of stockholders entitled to
vote at any meeting of stockholders, arranged in alphabetical order for each
class of stock and showing the address of each such stockholder and the number
of shares registered in his or her name, shall be open to the examination of any
such stockholder, for any purpose germane to the meeting, during ordinary
business hours for a period of at least ten (10) days prior to the meeting,
either at a place within the city where the meeting is to be held, which place
shall be specified in the notice of the meeting, or if not so specified, at the
place where the meeting is to be held.


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         The stock list shall also be kept at the place of the meeting during
the whole time thereof and shall be open to the examination of any such
stockholder who is present. This list shall presumptively determine the identity
of the stockholders entitled to vote at the meeting and the number of shares
held by each of them.

         Section 1.9 STOCKHOLDER ACTION BY WRITTEN CONSENT. Any action which may
be taken at any annual or special meeting of stockholders may be taken without a
meeting and without prior notice, if a consent in writing, setting forth the
actions so taken, is signed by the holders of outstanding shares having not less
than the minimum number of votes which would be necessary to authorize or take
such action at a meeting at which all shares entitled to vote thereon were
present and voted. All such consents shall be filed with the Secretary of the
Corporation and shall be maintained in the corporate records. Prompt notice of
the taking of a corporate action without a meeting by less than unanimous
written consent shall be given to those stockholders who have not consented in
writing.

                                   ARTICLE II
                               BOARD OF DIRECTORS

         Section 2.1 NUMBER AND TERM OF OFFICE. The number of directors shall be
a range of not less than five (5) nor more than nine (9), with the number of
directors initially set at seven (7). The minimum or maximum number of directors
provided by this Section 2.1 may be changed or a definite number fixed without
provision for an indefinite number, by the Board of Directors pursuant to a
resolution adopted by a majority of the total number of authorized directors
(whether or not there exist any vacancies in previously authorized directorships
at the time any such resolution is presented to the Board of Directors for
adoption). Each director shall hold office until his successor is elected and
qualified or until his earlier death, resignation, retirement, disqualification
or removal.

         Section 2.2 VACANCIES AND NEWLY CREATED DIRECTORSHIPS. Newly created
directorships resulting from any increase in the authorized number of directors
or any vacancies in the Board of Directors resulting from death, resignation,
retirement, disqualification, or other cause (other than removal from office by
a vote of the stockholders) may be filled only by a majority vote of the
directors then in office, though less than a quorum, and directors so chosen
shall hold office for a term expiring at the next annual meeting of
stockholders. No decrease in the number of directors constituting the Board of
Directors shall shorten the term of any incumbent director.

         Section 2.3 REMOVAL. Subject to the limitations stated in the
Certificate of Incorporation, any director, or the entire Board of Directors,
may be removed from office at any time, with or without cause, but only by the
affirmative vote of the holders of at least a majority of the voting power of
all of the then outstanding shares of stock of the Corporation entitled to vote
generally in the election of directors, voting together as a single class.
Vacancies in the Board of Directors resulting from such removal may be filled by
(i) a majority of the directors then in office, though less than a quorum, or
(ii) the stockholders at a special meeting of the stockholders properly called
for that purpose, by the vote of the holders of a majority of the shares
entitled to vote at such special meeting. Directors so chosen shall hold office
until the next annual meeting of stockholders.


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         Section 2.4 REGULAR MEETINGS. Regular meetings of the Board of
Directors shall be held at such place or places, on such date or dates, and at
such time or times as shall have been established by the Board of Directors and
publicized among all directors. A notice of each regular meeting shall not be
required.

         Section 2.5 SPECIAL MEETINGS. Special meetings of the Board of
Directors may be called by a majority of the directors then in office by the
Chairman of the Board or by the Chief Executive Officer and shall be held at
such place, on such date, and at such time as they or he shall fix. Notice of
the place, date, and time of each such special meeting shall be given each
director by whom it is not waived by mailing written notice not less than five
(5) days before the meeting (one (1) day before the meeting if delivered by an
overnight courier service and two (2) days before the meeting if by overseas
courier service) or by telephoning, telecopying, telegraphing or personally
delivering the same not less than twenty-four (24) hours before the meeting.
Unless otherwise indicated in the notice thereof, any and all business may be
transacted at a special meeting.

         Section 2.6 QUORUM. At any meeting of the Board of Directors, a
majority of the total number of authorized directors shall constitute a quorum
for all purposes. If a quorum shall fail to attend any meeting, a majority of
those present may adjourn the meeting to another place, date, or time, without
further notice or waiver thereof.

         Section 2.7 PARTICIPATION IN MEETINGS BY CONFERENCE TELEPHONE. Members
of the Board of Directors, or of any committee of the Board of Directors, may
participate in a meeting of such Board or committee by means of conference
telephone or similar communications equipment by means of which all persons
participating in the meeting can hear each other and such participation shall
constitute presence in person at such meeting.

         Section 2.8 CONDUCT OF BUSINESS. At any meeting of the Board of
Directors, business shall be transacted in such order and manner as the Board of
Directors may from time to time determine, and all matters shall be determined
by the vote of a majority of the directors present, except as otherwise provided
herein or required by law. Action may be taken by the Board of Directors without
a meeting if all members thereof consent thereto in writing, and the writing or
writings are filed with the minutes of proceedings of the Board of Directors.

         Section 2.9 POWERS. The Board of Directors may, except as otherwise
required by law, exercise all such powers and do all such acts and things as may
be exercised or done by the Corporation, including, without limiting the
generality of the foregoing, the unqualified power:

                  (1) To declare dividends from time to time in accordance with
law;

                  (2) To purchase or otherwise acquire any property, rights or
privileges on such terms as it shall determine;

                  (3) To authorize the creation, making and issuance, in such
form as it may determine, of written obligations of every kind, negotiable or
non-negotiable, secured or unsecured, and to do all things necessary in
connection therewith;


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                  (4) To remove any officer of the Corporation with or without
cause, and from time to time to pass on the powers and duties of any officer
upon any other person for the time being;

                  (5) To confer upon any officer of the Corporation the power to
appoint, remove and suspend subordinate officers, employees and agents;

                  (6) To adopt from time to time such stock option, stock
purchase, bonus or other compensation plans for directors, officers, employees
and agents of the Corporation and its subsidiaries as it may determine;

                  (7) To adopt from time to time such insurance, retirement, and
other benefit plans for directors, officers, employees and agents of the
Corporation and its subsidiaries as it may determine; and

                  (8) To adopt from time to time regulations, not inconsistent
with these Bylaws, for the management of the Corporation's business and affairs.

         Section 2.10 COMPENSATION OF DIRECTORS. Directors, as such, may
receive, pursuant to resolution of the Board of Directors, fixed fees and other
compensation for their services as directors, including, without limitation,
their services as members of committees of the Board of Directors.

         Section 2.11 NOMINATION OF DIRECTOR CANDIDATES. Nominations for the
election of directors may be made by the Board of Directors or a proxy committee
appointed by the Board of Directors or by any stockholder entitled to vote in
the election of directors.

                                   ARTICLE III
                                   COMMITTEES

         Section 3.1 COMMITTEES OF THE BOARD OF DIRECTORS. The Board of
Directors, by a vote of a majority of the whole Board of Directors, may from
time to time designate committees of the Board of Directors, with such lawfully
delegable powers and duties as it thereby confers, to serve at the pleasure of
the Board of Directors and shall, for those committees and any others provided
for herein, elect a director or directors to serve as the member or members,
designating, if it desires, other directors as alternate members who may replace
any absent or disqualified member at any meeting of the committee. Any committee
so designated may exercise the power and authority of the Board of Directors to
declare a dividend, to authorize the issuance of stock or to adopt an agreement
of merger or consolidation if the resolution which designates the committee or a
supplemental resolution of the Board of Directors shall so provide. In the
absence or disqualification of any member of any committee and any alternate
member in his place, the member or members of the committee present at the
meeting and not disqualified from voting, whether or not he or she or they
constitute a quorum, may by unanimous vote appoint another member of the Board
of Directors to act at the meeting in the place of the absent or disqualified
member.


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         Section 3.2 CONDUCT OF BUSINESS. Each committee may determine the
procedural rules for meeting and conducting its business and shall act in
accordance therewith, except as otherwise provided herein or required by law.
Adequate provision shall be made for notice to members of all meetings;
one-third of the authorized members shall constitute a quorum unless the
committee shall consist of one or two members, in which event one member shall
constitute a quorum; and all matters shall be determined by a majority vote of
the members present. Action may be taken by any committee without a meeting if
all members thereof consent thereto in writing, and the writing or writings are
filed with the minutes of the proceedings of such committee.

                                   ARTICLE IV
                                    OFFICERS

         Section 4.1 GENERALLY. The officers of the Corporation shall consist of
a Chief Executive Officer, a Secretary and a Chief Financial Officer. The
Corporation may also have, at the discretion of the Board of Directors, a
Chairman of the Board, one or more Vice Presidents, and such other officers as
may from time to time be appointed by the Board of Directors. Officers shall be
elected by the Board of Directors, which shall consider that subject at its
first meeting after every annual meeting of stockholders. Each officer shall
hold office until his or her successor is elected and qualified or until his or
her earlier resignation or removal. Any number of offices may be held by the
same person.

         Section 4.2 CHAIRMAN OF THE BOARD. The Chairman of the Board, if there
shall be such an officer, shall, if present, preside at all meetings of the
Board of Directors, and exercise and perform such other powers and duties as may
be from time to time assigned to him by the Board of Directors or as provided by
these Bylaws.

         Section 4.3 CHIEF EXECUTIVE OFFICER. Subject to such supervisory
powers, if any, as may be given by the Board of Directors to the Chairman of the
Board, if there be such an officer, the Chief Executive Officer shall be the
general manager and chief operating officer of the Corporation and shall,
subject to the control of the Board of Directors, have general supervision,
direction, and control of the business and officers of the Corporation. He shall
preside at all meetings of the stockholders. He shall be ex officio a member of
all the standing committees, including the executive committee, if any, and
shall have the general powers and duties of management usually vested in the
office of chief executive officer of a Corporation, and shall have such other
powers and duties as may be prescribed by the Board of Directors or by these
Bylaws.

         Section 4.4 VICE PRESIDENT. In the absence or disability of the Chief
Executive Officer, the Vice Presidents in order of their rank as fixed by the
Board of Directors, or if not ranked, the Vice President designated by the Board
of Director, shall perform the duties of the Chief Executive Officer, and when
so acting shall have all the powers of, and be subject to all the restrictions
upon, the Chief Executive Officer. The Vice Presidents shall have such other
powers and perform such other duties as from time to time may be prescribed for
them respectively by the Board of Directors or these Bylaws.


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         Section 4.5 CHIEF FINANCIAL OFFICER. Unless otherwise designated by the
Board of Directors, the Chief Financial Officer shall be the Treasurer. The
Chief Financial Officer shall keep and maintain or cause to be kept and
maintained, adequate and correct books and records of account in written form or
any other form capable of being converted into written form.

         The Chief Financial Officer shall deposit all monies and other
valuables in the name and to the credit of the Corporation with such
depositaries as may be designated by the Board of Directors. He shall disburse
all funds of the Corporation as may be ordered by the Board of Directors, shall
render to the Chief Executive Officer and directors, whenever they request it,
an account of all of his transactions as Chief Financial Officer and of the
financial condition of the Corporation, and shall have such other powers and
perform such other duties as may be prescribed by the Board of Directors or by
these Bylaws.

         Section 4.6 SECRETARY. The Secretary shall keep, or cause to be kept, a
book of minutes in written form of the proceedings of the Board of Directors,
committees of the Board of Directors, and stockholders. Such minutes shall
include all waivers of notice, consents to the holding of meetings, or approvals
of the minutes of meetings executed pursuant to these Bylaws or the Delaware
General Corporation Law. The Secretary shall keep, or cause to be kept at the
principal executive office or at the office of the Corporation's transfer agent
or registrar, a record of its stockholders, giving the names and addresses of
all stockholders and the number and class of shares held by each.

         The Secretary shall give or cause to be given, notice of all meetings
of the stockholders and of the Board of Directors required by these Bylaws or by
law to be given, and shall keep the seal of the Corporation in safe custody, and
shall have such other powers and perform such other duties as may be prescribed
by the Board of Directors or these Bylaws.

         Section 4.7 DELEGATION OF AUTHORITY. The Board of Directors may from
time to time delegate the powers or duties of any officer to any other officers
or agents, notwithstanding any provision hereof.

         Section 4.8 REMOVAL. Any officer of the Corporation may be removed at
any time, with or without cause, by the Board of Directors.

         Section 4.9 ACTION WITH RESPECT TO SECURITIES OF OTHER CORPORATIONS.
Unless otherwise directed by the Board of Directors, the Chief Executive Officer
or any officer of the Corporation authorized by the Chief Executive Officer
shall have power to vote and otherwise act on behalf of the Corporation, in
person or by proxy, at any meeting of stockholders of or with respect to any
action of stockholders of any other corporation in which this Corporation may
hold securities and otherwise to exercise any and all rights and powers which
this Corporation may possess by reason of its ownership of securities in such
other corporation.

                                    ARTICLE V
                                      STOCK

         Section 5.1 CERTIFICATES OF STOCK. Each stockholder shall be entitled
to a certificate signed by, or in the name of the Corporation by, the Chairman
or Vice-Chairman, if any, of the


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Board of Directors, or the Chief Executive Officer or a Vice President, and by
the Secretary or an Assistant Secretary, or the Treasurer or an Assistant
Treasurer, certifying the number of shares owned by him or her. Any of or all
the signatures on the certificate may be facsimile.

         Section 5.2 TRANSFERS OF STOCK. Transfers of stock shall be made only
upon the transfer books of the Corporation kept at an office of the Corporation
or by transfer agents designated to transfer shares of the stock of the
Corporation. Except where a certificate is issued in accordance with Section 5.4
of these Bylaws, an outstanding certificate for the number of shares involved
shall be surrendered for cancellation before a new certificate is issued
therefor.

         Section 5.3 RECORD DATE. The Board of Directors may fix a record date,
which shall not be more than sixty (60) nor fewer than ten (10) days before the
date of any meeting of stockholders, nor more than sixty (60) days prior to the
time for the other action hereinafter described, as of which there shall be
determined the stockholders who are entitled: to notice of or to vote at any
meeting of stockholders or any adjournment thereof; to receive payment of any
dividend or other distribution or allotment of any rights; or to exercise any
rights with respect to any change, conversion or exchange of stock or with
respect to any other lawful action.

         Section 5.4 LOST, STOLEN OR DESTROYED CERTIFICATES. In the event of the
loss, theft or destruction of any certificate of stock, another may be issued in
its place pursuant to such regulations as the Board of Directors may establish
concerning proof of such loss, theft or destruction and concerning the giving of
a satisfactory bond or bonds of indemnity.

         Section 5.5 REGULATIONS. The issue, transfer, conversion and
registration of certificates of stock shall be governed by such other
regulations as the Board of Directors may establish.

                                   ARTICLE VI
                                     NOTICES

         Section 6.1 NOTICES. Except as otherwise specifically provided herein
or required by law, all notices required to be given to any stockholder,
director, officer, employee or agent shall be in writing and may in every
instance be effectively given by hand delivery to the recipient thereof, by
depositing such notice in the mails, postage paid, or by sending such notice by
prepaid telegram, mailgram, telecopy or commercial courier service. Any such
notice shall be addressed to such stockholder, director, officer, employee or
agent at his or her last known address as the same appears on the books of the
Corporation. The time when such notice shall be deemed to be given shall be the
time such notice is received by such stockholder, director, officer, employee or
agent, or by any person accepting such notice on behalf of such person, if hand
delivered, or the time such notice is dispatched, if delivered through the mails
or by telegram, courier or mailgram.

         Section 6.2 WAIVERS. A written waiver of any notice, signed by a
stockholder, director, officer, employee or agent, whether before or after the
time of the event for which notice is to be given, shall be deemed equivalent to
the notice required to be given to such stockholder, director, officer, employee
or agent. Neither the business nor the purpose of any meeting need be specified
in such a waiver. Attendance of a person at a meeting shall constitute


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a waiver of notice for such meeting, except when the person attends a meeting
for the express purpose of objecting, at the beginning of the meeting, to the
transaction of any business because the meeting is not lawfully called or
convened.

                                   ARTICLE VII
                                  MISCELLANEOUS

         Section 7.1 FACSIMILE SIGNATURES. In addition to the provisions for use
of facsimile signatures elsewhere specifically authorized in these Bylaws,
facsimile signatures of any officer or officers of the Corporation may be used
whenever and as authorized by the Board of Directors or a committee thereof.

         Section 7.2 CORPORATE SEAL. The Board of Directors may provide a
suitable seal, containing the name of the Corporation, which seal shall be in
the charge of the Secretary. If and when so directed by the Board of Directors
or a committee thereof, duplicates of the seal may be kept and used by the Chief
Financial Officer or by an Assistant Secretary or other officer designated by
the Board of Directors.

         Section 7.3 RELIANCE UPON BOOKS, REPORTS AND RECORDS. Each director,
each member of any committee designated by the Board of Directors, and each
officer of the Corporation shall, in the performance of his duties, be fully
protected in relying in good faith upon the books of account or other records of
the Corporation, including reports made to the Corporation by any of its
officers, by an independent certified public accountant, or by an appraiser.

         Section 7.4 FISCAL YEAR. The fiscal year of the Corporation shall be as
fixed by the Board of Directors.

         Section 7.5 TIME PERIODS. In applying any provision of these Bylaws
which require that an act be done or not done a specified number of days prior
to an event or that an act be done during a period of a specified number of days
prior to an event, calendar days shall be used, the day of the doing of the act
shall be excluded, and the day of the event shall be included.

                                  ARTICLE VIII
                    INDEMNIFICATION OF DIRECTORS AND OFFICERS

         Section 8.1 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 of the
Corporation or is or was serving at the request of the Corporation as a director
or officer of another corporation, or as a controlling person 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 or employee or in any other
capacity while serving as a director or officer, 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 any such amendment, only to the extent that such amendment permits
the Corporation to provide broader indemnification rights


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than said Law permitted the Corporation to provide prior to such amendment)
against all expenses, liability and loss 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 or officer and shall inure to the benefit
of his or her heirs, executors and administrators; PROVIDED, HOWEVER, that,
except as provided in Section 8.2, 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 (a) such indemnification is
expressly required to be made by law, (b) the action, suit or proceeding (or
part thereof) was authorized by the Board of Directors, (c) such indemnification
is provided by the Corporation, in its sole discretion, pursuant to the powers
vested in the Corporation under the Delaware General Corporation Law, or (d) the
action, suit or proceeding (or part thereof) is brought to establish or enforce
a right to indemnification under an indemnity agreement or any other statute or
law or otherwise as required under Section 145 of the Delaware General
Corporation Law. The rights hereunder shall be contract rights and shall include
the right to be paid by the Corporation expenses incurred in defending any such
proceeding in advance of its final disposition; PROVIDED, HOWEVER, that, if the
Delaware General Corporation Law then so requires, 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.

         Section 8.2 RIGHT OF CLAIMANT TO BRING SUIT. If a claim under Section
8.1 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 such suit is not frivolous or brought in bad faith, 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 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 a claimant has not
met such applicable standard of conduct.

         Section 8.3 NON-EXCLUSIVITY OF RIGHTS. The rights conferred on any
person by Sections 8.1 and 8.2 shall not be exclusive of any other right which
such persons may have or


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hereafter acquire under any statute, provision of the Certificate of
Incorporation, bylaw, agreement, vote of stockholders or disinterested directors
or otherwise.

         Section 8.4 INDEMNIFICATION CONTRACTS. The Board of Directors is
authorized to enter into a contract with any director, officer, employee or
agent of the Corporation, or any person serving at the request of the
Corporation as a director, officer, employee or agent of another corporation,
partnership, joint venture, trust or other enterprise, including employee
benefit plans, providing for indemnification rights equivalent to or, if the
Board of Directors so determines, greater than, those provided for in this
Article VIII.

         Section 8.5 INSURANCE. The Corporation may maintain insurance to the
extent reasonably available, at its expense, to protect itself and any such
director, officer, employee or agent of the Corporation or another corporation,
partnership, joint venture, trust or other enterprise against any such expense,
liability or loss, whether or not the Corporation would have the power to
indemnify such person against such expense, liability or loss under Delaware
General Corporation Law.

         Section 8.6 EFFECT OF AMENDMENT. Any amendment, repeal or modification
of any provision of this Article VIII by the stockholders or the directors of
the Corporation shall not adversely affect any right or protection of a director
or officer of the Corporation existing at the time of such amendment, repeal or
modification.

                                   ARTICLE IX
                                   AMENDMENTS

         The Board of Directors is expressly empowered to adopt, amend or repeal
these Bylaws, subject to the right of the stockholders to adopt, amend, alter or
repeal these Bylaws. Any adoption, amendment or repeal of these Bylaws by the
Board of Directors shall require the approval of a majority of the total number
of authorized directors (whether or not there exist any vacancies in previously
authorized directorships at the time any resolution providing for adoption,
amendment or repeal is presented to the Board of Directors). The stockholders
shall also have power to adopt, amend or repeal these Bylaws.


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<Page>


                     SECRETARY'S CERTIFICATE OF ADOPTION OF

                                  THE BYLAWS OF

                                  MITOKOR, INC.


         I hereby certify:

         That I am the duly elected Secretary of MitoKor, Inc., a Delaware
corporation;

         That the foregoing Bylaws comprising eleven (11) pages, constitute the
Bylaws of said corporation as duly adopted by the sole incorporator of the
Corporation on March 7, 2002 and by the sole Director of the Corporation on
March 7, 2002.

         IN WITNESS WHEREOF, I have hereunder subscribed my name this 7th day of
March, 2002.



                                           /s/ Craig Johnson
                                           -------------------------------------
                                           Craig Johnson, Secretary


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