Exhibit B
    Ophidian Pharmaceuticals, Inc.  Proxy Statement

            OPHIDIAN PHARMACEUTICALS, INC.

          Plan of Dissolution and Liquidation

     This Plan of Dissolution and Liquidation (this
"Plan") is intended to accomplish the dissolution and
complete liquidation of Ophidian Pharmaceuticals, Inc.,
a Delaware corporation (the "Company"), in accordance
with Section 275 and other applicable provisions of the
General Corporation Law of Delaware ("DGCL") and
Section 331 of the Internal Revenue Code of 1986, as
amended (the "Code").

1.   Approval and Adoption of the Plan by the Board of
Directors.  The Company's Board of Directors (the
"Board") has adopted the Plan and called a meeting of
the Company's holders of Common Stock, par value
$0.0025, (the "Stockholders") to approve the Plan.

2.   Approval of the Plan by the Stockholders.  If the
Plan is approved by the Stockholders, the Plan shall
constitute the adopted Plan of the Company as of the
date on which the Stockholder approval is obtained (the
"Adoption Date").  The Company shall file a certificate
of dissolution ("Certificate of Dissolution") with the
Secretary of State of the State of Delaware in
accordance with the DGCL immediately after the Adoption
Date; provided, however, that the Board is authorized,
in its absolute discretion as it deems necessary,
appropriate or advisable, to delay the filing of the
Certificate of Dissolution until after the Company has
completed the sale of substantially all of its assets
to Promega Corporation.  The dissolution shall be
effective upon the filing of the Certificate of
Dissolution or such later date within ninety (90) days
of the filing of the Certificate of Dissolution as
specified in the Certificate of Dissolution (the
"Effective Date").

3.   Dissolution and Liquidation Period.  Following the
Effective Date, the Company shall not engage in any
business activities except to the extent necessary to
preserve the value of its assets, wind up its business
affairs, including any liquidation of its assets, and
distribute its assets in accordance with this Plan.
Further, after the Effective Date, the steps set forth
below shall be completed at such times as the Board, in
its absolute discretion, deems necessary, appropriate
or advisable to maximize the value of the Company's
assets upon liquidation; provided that such steps may
not be delayed longer than is permitted by applicable
law.  Without limiting the generality of the foregoing,
the Board may instruct the officers of the Company to
delay the taking of any of the following steps until
the Company has performed such actions as the Board or
such officers determine to be necessary, appropriate or
advisable for the Company to maximize the value of the
Company's assets upon liquidation; provided, that such
steps may not be delayed longer than is permitted by
applicable law.

  a.   The cessation of all of the Company's business
  activities and the withdrawal of the Company from
  any jurisdiction in which it is qualified to do
  business, except and insofar as necessary for the
  sale of its assets and for the proper winding up of
  the Company pursuant to Section 278 of the DGCL;

  b.   The negotiation and consummation of sales of
  all of the assets and properties of the Company by
  the Company's officers, insofar and on such terms as
  the Board deems such sales to be necessary,
  appropriate or advisable;



  c.   In accordance with Section 281(b) of the DGCL,
  the payment and discharge of, or provision as will
  be reasonably likely to provide sufficient
  compensation for:

     (1)  all claims and obligations, including all
     contingent, conditional or unmatured contractual
     claims, known to the Company;

     (2)  any claim against the Company which is the
     subject of a pending action, suit or proceeding to
     which the Company is a party; and

     (3)  claims that have not been made known to the
     Company or that have not arisen but that, based on
     facts known to the Company, are likely to arise or
     to become known to the company within ten (10)
     years after the Effective Date.

  d.   The distribution of remaining funds of the Company
  and the remaining unsold assets of the Company, if
  any, to its stockholders.

4.   Authority of Officers and Directors.  After the
Effective Date, the Board and the officers of the
Company shall continue in their positions for the
purpose of winding up the affairs of the Company as
contemplated by Delaware law.  The Board may appoint
officers, hire employees and retain independent
contractors in connection with the winding up process,
and is authorized to pay to the Company's officers,
directors and employees, or any of them, compensation
or additional compensation above their regular
compensation, in money or other property, in
recognition of the extraordinary efforts they, or any
of them, will be required to undertake, or actually
undertake, in connection with the successful
implementation of this Plan.  Adoption of this Plan by
holders of a majority of the outstanding shares of
Common Stock shall constitute the approval of the
Company's Stockholders of the Board's authorization of
the payment of any such compensation.

  The adoption of the Plan by the Company's
Stockholders shall constitute full and complete
authority for the Board and the officers of the
Company, without further stockholder action, to do and
perform any and all acts and to make, execute and
deliver any and all agreements, conveyances,
assignments, transfers, certificates and other
documents of any kind and character which the Board or
such officers deem necessary, appropriate or advisable:
(i) to sell, dispose, convey, transfer and deliver the
assets of the Company (ii) to satisfy or provide for
the satisfaction of the Company's obligations in
accordance with Sections 281(b) of the DGCL, (iii) to
distribute all of the remaining funds of the Company
and any unsold assets of the Company to the Company's
stockholders, and (iv) to dissolve the Company in
accordance with the laws of the State of Delaware and
cause its withdrawal from all jurisdictions in which it
is authorized to do business.

5.   Conversion of Assets Into Cash or other
Distributable Form.  Subject to approval by the Board,
the officers, employees and agents of the Company
shall, as promptly as feasible and whether before or
after the Effective Date, proceed to collect all sums
due or owing to the Company, to sell and convert into
cash any and all corporate assets and, out of the
assets of the Company, to pay, satisfy and discharge or
make adequate provision for the payment, satisfaction



and discharge of all debts and liabilities of the
Company pursuant to Section 3 above, including all
expenses of the sale of assets and of the liquidation
and dissolution provided for by the Plan.

6.   Contingency Reserve.  If and to the extent deemed
necessary, appropriate or desirable by the Board in its
absolute discretion, the Company may establish and set
aside a reasonable amount (the "Contingency Reserve")
for the payment of expenses and liabilities, including
expenses in connection with completion of the Plan.

7.   Professional Fees and Expenses.  It is
specifically contemplated that the Board may authorize
the payment of a retainer fee to a law firm or law
firms selected by the Board for legal fees and expenses
of the Company, including, among other things, to cover
any costs payable pursuant to the indemnification of
the Company's officers or members of the Board provided
by the Company pursuant to its Certificate of
Incorporation and Bylaws or the DGCL or otherwise.

  In addition, in connection with and for the purpose
of implementing and assuring completion of this Plan,
the Company may, in the absolute discretion of the
Board, pay any brokerage, agency and other fees and
expenses of persons rendering services to the Company
in connection with the collection, sale, exchange or
other disposition of the Company's property and assets
and the implementation of this Plan.

8.   Indemnification.  The Company shall continue to
indemnify its officers and directors, in accordance
with its Bylaws and any contractual arrangements, for
actions taken in connection with this Plan and the
winding up of the affairs of the Company.  The Board,
in its absolute discretion, is authorized to obtain and
maintain insurance as may be necessary, appropriate or
advisable to cover the Company's obligations hereunder.

9.   Liquidating Trust.  The Board may, if the Board in
its absolute discretion deems it necessary, appropriate
or desirable, establish a liquidating trust (the
"Liquidating Trust") and transfer assets and
liabilities of the Company to the Liquidating Trust for
the purposes of prosecuting and defending suits, by or
against the company, enabling the company to settle and
close its business, to dispose of and convey the
property of the Company, to discharge the liabilities
of the Company and to distribute to the Company's
stockholders any remaining assets. The Board shall
determine, in its absolute discretion, whether and when
to transfer all of the Company's remaining assets to
the Liquidating Trust; provided, however, if all of the
Company's assets are not distributed within three years
of the Effective Date, the Company shall transfer all
of its remaining assets, including any Contingency
Reserve to the Liquidating Trust.

  The Liquidating Trust may be established by agreement
with one or more Trustees selected by the Board. If the
Liquidating Trust is established by agreement with one
or more Trustees, the trust agreement establishing and
governing the Liquidating Trust shall be in form and
substance determined by the Board.  In the alternative,
the Board may petition the Delaware Court of Chancery
for the appointment of one or more Trustees to conduct
the liquidation of the Company, subject to the
supervision of the Court. Whether appointed by an
agreement or by the Court, the  Trustees shall in
general be authorized to take charge of the Company's
property, and to collect the debts and property due and
belonging to the Company, with power to prosecute and
defend, in the name of the Company, or otherwise, all
such suits as may be necessary or proper



for the foregoing purposes, and to appoint an agent under
it and to do all other acts which might be done by the
Company that may be necessary, appropriate or advisable
for the final settlement of the unfinished business of
the Company.

10.  Liquidating Distributions.  Liquidating
distributions, in cash or in kind, shall be made from
time to time after the Effective Date, as provided in
Section 3 above, to the Company's stockholders, pro
rata in accordance with the respective number of shares
then held of record; provided that in the opinion of
the Board adequate provision has been made for the
payment, satisfaction and discharge of all known,
unascertained or contingent debts, obligations and
liabilities of the Company (including costs and
expenses incurred and anticipated to be incurred in
connection with the sale of assets and complete
liquidation of the Company). All determinations as to
the time for and the amount and kind of distributions
to stockholders shall be made in the exercise of the
absolute discretion of the Board and in accordance with
Section 281(b) of the DGCL.

  Any assets distributable to any creditor or
stockholder of the Company who is unknown or cannot be
found, or who is under a disability and for whom there
is no legal representative, shall escheat to the state
or be treated as abandoned property pursuant to
applicable state law.

11.  Abandonment of the Plan.  If for any reason the
Board determines that such action would be in the best
interests of the Company and its stockholders, it may
abandon the dissolution, the Plan and the transactions
contemplated hereby, notwithstanding stockholder
approval, to the extent permitted by the DGCL. Upon
such abandonment, the dissolution and the Plan shall be
void.

12.  Liquidation under Section 331.  It is intended
that this Plan shall be a plan of complete liquidation
within the terms of Section 331 of the Code.  The Plan
shall be deemed to authorize such action as, in the
opinion of counsel for the Company, may be necessary to
conform with the provisions of said Section 331.

13.  Filing of Tax Forms.  The appropriate officer of
the Company is authorized and directed, within thirty
(30) days after the Effective Date, to execute and file
a United States Treasury Form 966 pursuant to Section
6043 of the Code and such additional forms and reports
with the Internal Revenue Service as may be appropriate
in connection with this Plan and the carrying out
thereof.

14.  Board Authorization.  The Board is authorized,
without further action by the Company's Stockholders,
to do and perform, any and all acts, and to make,
execute, deliver or adopt any and all agreements,
resolutions, conveyances, certificates and other
documents of every kind which are deemed necessary,
appropriate or desirable, in the absolute discretion of
the Board, to implement this Plan and the transactions
contemplated hereby, including, without limiting the
foregoing, all filings or acts required by any state or
federal law or regulation to wind up its affairs.