Document:

<PAGE>
                                                                 EXHIBIT 10.30

ADVANCED PHOTON SOURCE
ARGONNE NATIONAL LABORATORY

================================================================================

                           MEMORANDUM OF UNDERSTANDING
                       BETWEEN THE ADVANCED PHOTON SOURCE
                                     AND THE
                  STRUCTURAL GENOMIX COLLABORATIVE ACCESS TEAM
                 FOR THE CONSTRUCTION AND OPERATION OF BEAMLINES
                          AT THE ADVANCED PHOTON SOURCE

                                   1. PURPOSE

The purpose of this Memorandum of Understanding (MOU) between the Advanced
Photon Source (APS) and the Structural GenomiX Collaborative Access Team
(SGX-CAT) is to provide SGC-CAT with access to sector number 31 for the
construction and operation of beamlines.

                                2. PREREQUISITES

SGC-CAT has met the four prerequisites for signing of this MOU:

o        Approval of the SGC-CAT proposal in accordance with the recommendations
         of the Proposal Evaluation Board.

o        Approval of the Conceptual Designs of the SGC-CAT beamlines.

o        Approval of the SGC-CAT Management Plan, the elements of which are
         subject to revision by mutual agreement of the parties as the project
         matures.

o        Receipt of appropriate documentation with respect to the funding intent
         of Structural GenomiX Inc.

         3. UNDERSTANDING BETWEEN THE ADVANCED PHOTON SOURCE AND SGC-CAT

During its tenure, SGC-CAT will develop and operate sector number 31, and it
will occupy the corresponding Laboratory/Office Module segment. SGC-CAT's tenure
begins on the date this MOU is signed, and will continue in accordance with the
provisions of the Advanced Photon Source User Policies and Procedures.

<PAGE>

The APS and SGC-CAT will operate in accordance with the following:

o        The Advanced Photon Source User Policies and Procedures.

o        The SGC-CAT Management Plan.

o        The SGC-CAT Conceptual Design for the beamlines and insertion device.

o        The Collaborative Access Team User Agreement for the Advanced Photon
         Source that will be executed with Structural GenomiX Inc.

                                  4. SIGNATURES

<Table>
<S>                                          <C>               <C>                                   <C>
         /s/Kevin L. D'Amica                    7/26/00              /s/David E. Moncton
----------------------------------------     -------------     ----------------------------------    --------------

            Kevin L. D'Amico                      Date                  David E. Moncton                  Date
                Director                                          Asociate Laboratory Director
                 SGX-CAT                                                   for the APS
</Table>

                                  WITNESSED BY:

<Table>
<S>                                          <C>               <C>                                   <C>
           /s/Yoon I. Chang                     7/26/00                  /s/Tim Harris                   7/26/00
----------------------------------------    --------------     ----------------------------------    --------------

              Yoon I. Chang                       Date                     Tim Harris                     Date
       Interim Laboratory Director                                      President and CEO
       Argonne National Laboratory                                   Structural GenomiX Inc.

       /s/Wayne Hendrickson                     7/26/00            /s/Don Micahel Randel                 7/26/00
----------------------------------------    --------------     ----------------------------------    --------------

            Wayne Hendrickson                     Date                 Don Michael Randel                 Date
      Professor of Biochemistry and                                         President
          Molecular Biophysics                                        University of Chicago
           Columbia University

          /s/Bill Richardson
----------------------------------------    --------------

             Bill Richardson                      Date
           Secretary of Energy
        U.S. Department of Energy
</Table>

<PAGE>

                            Collaborative Access Team
                                 User Agreement
                                     for the
                             Advanced Photon Source
                                       at
                           Argonne National Laboratory
                                Argonne, Illinois

This User Agreement is entered into by The University of Chicago, an Illinois
not-for-profit corporation, operator of Argonne National Laboratory and herein
also called "Argonne," acting under Prime Contract No. W-31-109-ENG-38, as
amended, with the United States Government (called "Government"), represented by
the U.S. Department of Energy (called "Department"); and Structural GenomiX,
Inc., an institutional member of the Structural GenomiX Collaborative Access
Team (SGX-CAT) and herein called "User."

In consideration of the mutual benefits flowing from this Agreement, the parties
agree as follows:

A.       DESCRIPTION OF WORK

         After securing prior Argonne approval, User shall be permitted to
         install beamlines and other equipment in designated areas of the
         Advanced Photon Source (APS) facility and in accordance with
         APS-approved designs, schedules, management plans, and safety
         practices; and to use those beamlines and supporting APS and Argonne
         facilities to perform experiments in accordance with APS-approved
         proposals and safety practices. Independent Investigators, selected by
         SGX-CAT in accordance with an APS-approved Independent Investigator
         Access Plan, shall be permitted to use designated SGX-CAT beamlines and
         supporting APS and Argonne facilities to perform research in accordance
         with APS-approved safety practices. The duration of each Independent
         Investigator's access to the designated beamline(s) will be specified
         by SGX-CAT. This Agreement shall apply to all future experiments which
         are totally funded by User and performed at APS facilities. This
         Agreement shall be incorporated by reference in each Supplemental
         Agreement which contains a nonproprietary statement describing an
         experiment authorized to be performed at the APS.

B.       PERSONNEL RELATIONSHIPS

         User shall be responsible for the acts or omissions of its employees
         and agents and of all other persons that User allows to participate in
         the activities under this Agreement except Independent Investigators,
         who are bound by another User Agreement.

         Individuals identified above for whom User is responsible and who are
         not actual employees of User shall be considered "employees" of User
         ONLY for the purposes of ownership of intellectual property in
         accordance with Attachment A. Such individuals will execute the
         Acknowledgment therefor.

<PAGE>
                                       2

C.       PAYMENT OF EXPENSES

         Before commencing activities at the Argonne APS Facility, User shall
         establish an account at Argonne to enable the purchase of goods and
         services from Argonne. User shall be responsible for all authorized
         expenses incurred by Argonne in providing services and supplies to or
         on behalf of User and for all actual services and supplies used by
         User's employees and guests at the APS facility. At the time when the
         account is established, Argonne shall notify User of the mechanism for
         making payment. At that time and as Argonne's provisional and direct
         overhead rates which are established consistent with Argonne and DOE
         pricing policy are revised, User will be informed of those rates.
         Whenever Argonne adjusts its provisional rates to actual rates, the
         User account will be charged or credited accordingly. User shall pay in
         advance for capital equipment items and construction activities
         purchased through Argonne.

D.       RIGHTS IN PATENTS, TECHNICAL DATA, AND COPYRIGHTS

         With respect to rights in patents, technical data, and copyrights, the
         terms and conditions of Attachment A shall apply to this Agreement.

E.       INDEMNITY AND LIABILITY

         Except to the extent of their negligence or intentional misconduct,
         neither the Government, the Department, The University of Chicago, nor
         persons acting on their behalf will be responsible for any injury to or
         death of persons or other living things or damage to or destruction of
         property or for any other loss, damage or injury of any kind whatsoever
         resulting from the performance of services or furnishings of materials
         hereunder.

         NEITHER THE GOVERNMENT, THE DEPARTMENT, THE UNIVERSITY OF CHICAGO, NOR
         PERSONS ACTING ON THEIR BEHALF MAKES ANY WARRANTY, EXPRESS OR IMPLIED
         (1) WITH RESPECT TO THE ACCURACY, COMPLETENESS OR USEFULNESS OF ANY
         INFORMATION FURNISHED HEREUNDER, (2) THAT THE USE OF ANY SUCH
         INFORMATION MAY NOT INFRINGE PRIVATELY OWNED RIGHTS, (3) THAT THE
         SERVICES, MATERIALS, OR INFORMATION FURNISHED HEREUNDER WILL NOT RESULT
         IN INJURY OR DAMAGE WHEN USED FOR ANY PURPOSE, AND (4) THAT THE
         SERVICES, MATERIALS OR INFORMATION FURNISHED HEREUNDER WILL ACCOMPLISH
         THE INTENDED RESULTS OR ARE SAFE FOR ANY PURPOSE INCLUDING THE INTENDED
         PURPOSE.

         Neither the Government, the Department, The University of Chicago, nor
         persons acting on their behalf will be responsible, irrespective of
         causes, for failure to perform the services or furnish the materials or
         information hereunder at any particular time or in any specific manner.
         Notwithstanding the foregoing, The University of Chicago's only rights
         to terminate this Agreement are set forth in Article I. below.

         To the extent permitted by law and to the extent of its negligence or
         intentional misconduct, User agrees to indemnify and save harmless the
         Government, the Department, The University of Chicago, and persons
         acting on their behalf from (1) all liability, including costs and
         expenses incurred, resulting from the User's use or disclosure of any
         information in whatever form, furnished hereunder, and (2) all
         liability to any persons including the User for injury to or death of
         persons or other living things or injury to or destruction of property
         arising out of performance by the Government, the Department,

<PAGE>
                                       3

         The University of Chicago, or persons acting on their behalf under this
         Agreement, or arising out of the use of the services performed,
         materials supplied, or information given hereunder by any person
         including the User, and not directly resulting from the fault or
         negligence of the Government, the Department, The University of
         Chicago, or persons acting on their behalf. The foregoing provisions
         shall have no application to public liability for nuclear incident as
         defined and provided for in the Atomic Energy Act of 1954, as amended.

         To the extent permitted by law, User agrees to indemnify the
         Government, the Department, The University of Chicago, and persons
         acting on their behalf against liability of any kind (including costs
         and expenses incurred) for the use, by or at the direction of User, of
         any invention or discovery and for the infringement of any Letters
         Patent (not including liability, arising pursuant to Section 183, Title
         35 (1952), U.S. Code, prior to the issuance of Letters Patent)
         occurring in the performance of this Agreement.

         User will be held liable for costs and expenses resulting from loss,
         damage, destruction, misuse, or alteration to or of Government property
         to the extent that such loss, damage, destruction, misuse, or
         alteration is caused or contributed to by the intentional or negligent
         act of User or its employees or representatives.

F.       SAFETY AND HEALTH

         User shall take all reasonable precautions in the installation of
         equipment and performance of experiments to protect the safety and
         health of others and to protect the environment, and shall comply with
         all applicable safety and health regulations and requirements of APS,
         Argonne, and the Department. In the event that User fails to comply
         with said regulations or requirements, Argonne may, without prejudice
         to any other legal or contractual rights, issue an order stopping all
         or any part of User's activities at the APS.

G.       THIRD-PARTY CONTRACTS

         Contracts between User and third parties for work on Argonne premises
         including, but not limited to, construction, installation, maintenance,
         and repair, will be subject to prior approval by the Department and
         Argonne. The Department and Argonne may require the insertion of
         specific terms and conditions into such contracts.

H.       OWNERSHIP AND DISPOSITION OF PROPERTY

         Property purchased with Argonne funds remains the property of Argonne
         unless the cost is fully reimbursed by User, in which case it becomes
         the property of User. Property purchased with User funds remains the
         property of User unless User formally transfers ownership of that
         property to Argonne. When this Agreement and all extensions thereof
         have terminated, User will have 60 days to remove its property from the
         APS facility at User's expense. Any User-owned property that is not
         removed from the APS facility by the end of this 60-day period will
         become the properly of Argonne or may be removed by Argonne at the
         expense of User.

<PAGE>
                                       4

I.       TERM OF THIS USER AGREEMENT

         This Agreement shall be effective on the date it is executed by the
         last party to sign it and shall continue through the period ending five
         years after SGX-CAT receives Approval to Operate its insertion device
         beamline, at which time this Agreement shall extend automatically for
         successive periods of one year each, unless sixty (60) days before the
         beginning of any such one-year period The University of Chicago
         notifies User in writing that this agreement shall not be extended. The
         foregoing is subject to the following:

         1.       User may terminate this Agreement effective any time with
                  thirty (30) days prior written notice.

         2.       The University of Chicago may terminate this Agreement in the
                  event of a breach of this Agreement by User, provided that The
                  University of Chicago has first notified User of such breach
                  and has given User thirty (30) days to cure said breach.

User: Structural GenomiX, Inc.

<Table>
<S>                                                           <C>
By  Linda Grais                                               Title    E.V.P.
   -------------------------------------------------------          -----------------------------------------------
          (Name of Authorized Officer, typed)

Signature   /s/  Linda Grais                                                 Date   5/15/01
          ---------------------------------------------------------------         ---------------------------------
</Table>

Argonne:

<Table>
<S>                                                           <C>
                                                                          Associate Laboratory Director for
By    Dr. David E. Moncton                                    Title          the Advanced Photon Source
   -------------------------------------------------------          -----------------------------------------------
          (Name of Authorized Officer)

Signature    /s/ [Illegible] for DEM                                         Date   5/15/01
          ---------------------------------------------------------------         ---------------------------------
</Table>

Note: Each "employee" of User who will participate in activities at Argonne
under this Agreement must execute an Acknowledgment of the Agreement.

<PAGE>

                                  ATTACHMENT A

1.   Patent Rights - User Facilities (Class Waiver)

(a)  Definitions

     (1) "User" means the person or entity with which this Agreement is made.

     (2) "Subject Invention" means any invention or discovery of the User,
conceived or first actually reduced to practice in the course of or under this
Agreement, and includes any art, method, process, machine, manufacture, design
or composition of matter or any new and useful improvement thereof, or any
variety of plants, whether patented or unpatented under the Patent Laws of the
United States of America or any foreign country.

     (3) "Facility Operator" means the operating contractor which manages and
operates the Government-owned, contractor-operated facility where the work under
this Agreement is to be performed.

     (4) "Patent Counsel" means the DOE Patent Counsel assisting the Facility
Operator.

(b)  Rights of the User

     (1)  Election to Retain Rights.

          Subject to the provisions of Paragraph (c)(2) of this clause, the User
may retain the entire right, title and interest in any patent application filed
in any country on a Subject Invention reported and elected in accordance with
paragraph (d) of this clause and in any resulting patent secured by the User.
Where appropriate, the filing of patent applications by the User is subject to
DOE security regulations and requirements.

     (2)  Minimum License.

          The User reserves an irrevocable, nonexclusive, paid-up license in
each patent application filed in any country on a Subject Invention and any
resulting patent in which the User does not elect to retain title or in which
the Government acquires title. The license shall extend to the User's domestic
subsidiaries and affiliates, if any, within the corporate structure of which the
User is a part and shall include the right to grant sublicenses of the same
scope to the extent the User was legally obligated to do so at the time this
Agreement was entered into. The license shall be transferable only with approval
of DOE except when transferred to the successor of that part of the User's
business to which the invention pertains.

(c)  Rights of Government

     (1)  Assignment to the Government.

          The User agrees to assign to the Government, upon request, the entire
right, title, and interest in any country to each Subject Invention of the User
except to the extent that Rights are retained by the User under Paragraph (b)(2)
of this clause, where the User:

          (i) Does not elect pursuant to this clause to retain such rights; or

          (ii) Fails to have a patent application filed in that country on the
Subject Invention or decides not to continue prosecution or not to pay any
maintenance fees covering the invention; or

<PAGE>
                               Attachment A -- p.2

          (iii) At any time, the User no longer desires to retain title.

     (2) Terms and Conditions of Waived Rights.

          (i) To preserve the Government's residual Rights to Subject
Inventions, the User shall take all actions in reporting, electing, filing on,
prosecuting and maintaining invention Rights promptly, but in any event, in
sufficient time to satisfy domestic and foreign statutory and regulatory time
requirements, or, if the User decides not to take appropriate steps to protect
the invention rights, it shall notify DOE in sufficient time to permit the
Government to file, prosecute and maintain patent applications and any resulting
patents prior to the end of such domestic or foreign statutory or regulatory
time requirements.

          (ii) The User shall convey or assure the conveyance of any executed
instruments necessary to vest in the Government the rights set forth in this
clause.

          (iii) With respect to any Subject Invention in which the User retains
title, the Government shall have a nonexclusive, nontransferable, irrevocable,
paid-up license to practice or have practiced for or on behalf of the United
States the Subject Invention throughout the world.

          (iv) The User shall provide the Government a copy of any application
filed on a Subject Invention promptly after such application is filed, including
its serial number and filing date.

          (v) The User agrees to submit on request periodic reports no more
frequently than annually on the utilization of a Subject Invention or on efforts
at obtaining such utilization that are being made by the User or its licensees
or assignees. Such reports shall include information regarding the status of
development, date of first commercial sale or use, gross royalties received by
the User, and such other data and information as DOE may reasonably specify. The
User also agrees to provide additional reports as may be requested by DOE in
connection with any march-in proceeding undertaken by DOE in accordance with
paragraph (c)(2)(vii) of this clause. To the extent data or information supplied
under this paragraph is considered by the User, its licensee or assignee to be
privileged and confidential and is so marked, DOE agrees that, to the extent
permitted by 35 USC 202(c)(5), it will not disclose such information to persons
outside the Government.

          (vi) Notwithstanding any other provision of this clause, the User
agrees that neither it nor any assignee will grant to any person the exclusive
right to use or sell any Subject Invention in the United States unless such
person agrees that any products embodying the Subject Invention or produced
through the use of the Subject Invention will be manufactured substantially in
the United States. However, in individual cases, the requirement for such an
Agreement may be waived by DOE upon a showing by the User or its assignee that
reasonable but unsuccessful efforts have been made to grant licenses on similar
terms to potential licensees that would be likely to manufacture substantially
in the United States or that under the circumstances domestic manufacture is not
commercially feasible.

          (vii) The User agrees that with respect to any Subject Invention in
which it has acquired title, DOE has the right in accordance with the procedures
in 37 CFR 401.6 and any supplemental regulations of DOE to require the User, an
assignee or exclusive licensee of a Subject Invention to grant a nonexclusive,
partially exclusive, or exclusive license in any field of use to a responsible
applicant or applicants upon terms that are reasonable under the circumstances,
and if the User, assignee, or exclusive licensee refuses such a request, DOE has
the right to grant such a license itself if DOE determines that:

<PAGE>
                               Attachment A -- p.3

          (1) Such action is necessary because the User or assignee has not
taken, or is not expected to take within a reasonable time, effective steps to
achieve practical application of the Subject Invention in such field of use;

          (2) Such action is necessary to alleviate health or safety needs which
are not reasonably satisfied by the User, assignee, or their licensees;

          (3) Such action is necessary to meet requirements for public use
specified by federal regulations and such requirements are not reasonably
satisfied by the User, assignee or licensee; or

          (4) Such action is necessary because the Agreement required by
paragraph (c)(2)(vi) of this clause has not been obtained or waived or because a
licensee of the exclusive right to use or sell any Subject Invention in the
United States is in breach of such Agreement.

(d)  Invention Identification, Disclosures, and Reports

     The User shall furnish the Patent Counsel a written report containing full
and complete technical information concerning each Subject Invention of the User
within 6 months after conception or first actual reduction to practice (or such
longer period as may be authorized by Patent Counsel for good cause shown in
writing by User), whichever occurs first, in the course of or under this
Agreement, but in any event prior to any on sale, public use or public
disclosure of the Subject Invention known to the User. The report shall identify
the Agreement and inventor and shall be sufficiently complete in technical
detail and appropriately illustrated by sketch or diagram to convey to one
skilled in the art to which the Subject Invention pertains a clear understanding
of the nature, purpose, operation, and to the extent known, the physical,
chemical, biological, or electrical characteristics of the Subject Invention.
The report should also include any election of patent rights under this clause.
When an invention is reported under this paragraph (d), it shall be presumed to
have been made in the manner specified in Section (a)(1) and (2) of 42 USC 5908
and protectable when marked as confidential under 35 USC 205.

(e)  Limitation of Rights

     Nothing contained in this patent rights clause shall be deemed to give the
Government any rights with respect to any invention other than a Subject
Invention except as set forth in the Facilities License of paragraph (f).

(f)  Facilities License

     In addition to the rights of the parties with respect to inventions or
discoveries conceived or first actually reduced to practice in the course of or
under this Agreement, the User agrees to and does hereby grant to the Government
an irrevocable, nonexclusive paid-up license in and to any inventions or
discoveries regardless of when conceived or actually reduced to practice or
acquired by the User, which at any time through completion of this Agreement are
owned or controlled by the User and are incorporated in the facility as a result
of this Agreement to such an extent that the facility is not restored to the
condition existing prior to the Agreement (1) to practice or to have practiced
by or for the Government at the facility, and (2) to transfer such license with
the transfer of that facility. The acceptance or exercise by the Government of
the aforesaid rights and license shall not prevent the Government at anytime
from contesting the enforceability, validity or scope of, or title to, any
rights or patents herein licensed.

<PAGE>
                               Attachment A -- p.4

2.   Rights in Technical Data - Short Form

(a)  Definitions

     (1) The definitions of terms set forth in 48 CFR 52.227-14 apply to the
extent these terms are used herein.

     (2) "Contracting Officer" means the DOE entity having contract authority
over the Facility and Facility Operator.

(b)  Allocation of Rights

     (1)  The Government shall have:

          (i) Unlimited rights in technical data first produced in the
performance of this Agreement; unlimited rights in technical data not first
produced in the performance of this Agreement which is incorporated in technical
data delivered under this Agreement or which is not removed from the facility at
the termination of this Agreement;

          (ii) The right of the Contracting Officer or his representatives to
inspect at all reasonable times up to three years after final payment under this
Agreement all technical data first produced in the performance of this Agreement
(for which inspection the User or its subcontractor shall afford proper
facilities to DOE); and

          (iii) The right to have any technical data first produced in the
performance of this Agreement delivered to the Government as the Contracting
Officer may from time to time direct during the progress of the work, or in any
event as the Contracting Officer shall direct upon completion or termination of
this Agreement.

     (2)  The User shall have:

          The right to use for its private purposes, subject to patent, security
or other provisions of this Agreement, technical data it first produces in the
performance of this Agreement provided the data requirements of this Agreement
have been met as of the date of the private use of such data. The User agrees
that to the extent it receives or is given access to proprietary data or other
technical, business or financial data in the form of recorded information from
DOE or a DOE User or subcontractor, the User shall treat such data in accordance
with any restrictive legend contained thereon, unless use is specifically
authorized by prior written approval of the Contracting Officer.

(c)  Copyrighted Material

     (1) The User agrees to, and does hereby grant to the Government, and to its
officers, agents, servants and employees acting within the scope of their
duties:

          (i) A royalty-free, nonexclusive, irrevocable license to reproduce,
translate, publish, use, and dispose of and to authorize others so to do, all
copyrightable material first produced or composed in the performance of this
Agreement by the User, its employees or any individual or concern specifically
employed or assigned to originate and prepare such material; and

          (ii) A license as aforesaid under any and all copyrighted or
copyrightable works not first produced or composed by the User in the
performance of this Agreement but which are incorporated in the material
furnished under the Agreement, provided that such license

<PAGE>
                               Attachment A -- p.5

shall be only to the extent the User now has, or prior to completion or final
settlement of the Agreement may acquire, the right to grant such license without
becoming liable to pay compensation to others solely because of such grant.

     (2) The User agrees that it will not knowingly include any material
copyrighted by others in any written or copyrightable material furnished or
delivered under this Agreement without a license as provided for in subparagraph
(l)(ii) hereof, or without the consent of the copyright owner, unless it obtains
specific written approval of the Contracting Officer for the inclusion of such
copyrighted material.

3.   Notice and Assistance Regarding Patent and Copyright Infringement

(a) The User shall report to the Government, promptly and in reasonable written
detail, each notice or claim of patent or copyright infringement based on the
performance of this Agreement of which the User has knowledge.

(b) In the event of any claim or suit against the Government on account of any
alleged patent or copyright infringement arising out of the performance of this
Agreement or out of the use of any supplies furnished or work or services
performed hereunder, the User shall furnish to the Government when requested by
the Government, all evidence and information in possession of the User
pertaining to such suit or claim. Such evidence and information shall be
furnished at the expense of the Government except where the User has agreed to
indemnify the Government.<PAGE>
                                                                   Exhibit 10.31

                       MASTER LOAN AND SECURITY AGREEMENT

NO. 2081008                                               DATED: AUGUST 28, 2002

LENDER:                                       BORROWER:
         OXFORD FINANCE CORPORATION                    STRUCTURAL GENOMIX, INC.
         A Maryland corporation                        a Delaware corporation
Address:                                      Address:
         133 NORTH FAIRFAX STREET                      10505 ROSELLE STREET
         ALEXANDRIA, VIRGINIA 22314                    SAN DIEGO, CA 92121

      Borrower hereby agrees with Lender that, whenever Borrower shall be at any
time or times directly or contingently indebted, liable or obligated to Lender
in any manner whatsoever, Lender shall have the following rights:

      1. DEFINITIONS. To the extent not otherwise specifically defined in this
Agreement, unless the context otherwise requires, all other terms contained in
this Agreement shall have the meanings assigned or referred to them in the UCC.
The following terms shall have the following meanings:

      "Acceptance Date" with respect to each item of Equipment shall have the
meaning assigned to such term in Section 3 of this Agreement.

      "Affiliate" shall mean, with respect to any person, firm or entity, any
other person, firm or entity controlling, controlled by, or under common control
with such person, firm or entity; for the purposes hereof "control" shall mean
the possession, directly or indirectly, of the power to direct or cause the
direction of the management and policies of any such person, firm or entity,
whether through the legal or beneficial ownership of voting securities, by
contract or otherwise.

      "Agreement" shall mean this Master Loan and Security Agreement, as amended
or modified from time to time.

      "Attorneys' Fees and Expenses" shall mean all reasonable attorneys' fees
and legal costs and expenses (including, without limitation, those fees, costs
and expenses incurred in connection with bankruptcy proceedings, including
Relief from Stay Motions, Cash Collateral Motions and disputes concerning any
proposed disclosure statement and/or bankruptcy plan).

      "Collateral" shall mean all Equipment or other tangible or intangible
property ancillary to the Equipment and acquired in the same transaction as the
Equipment and all products, proceeds, rents and profits therefrom or thereof
including proceeds in the form of goods, accounts, chattel paper, documents,
instruments and insurance proceeds.

      "Default" shall have the meaning ascribed to such term in Section 7 of
this Agreement.

      "Equipment" shall mean one or more items or units of personal property now
owned or hereafter acquired by Borrower, as described in each Equipment
Schedule, wherever the same may be located, including all present and future
additions, attachments, accessions and accessories thereto and all replacements,
substitutions and a right to use license for any software related to any of the
foregoing and proceeds thereof, including all proceeds of insurance thereon.

      "Equipment Schedule" shall mean each Equipment Schedule, which
incorporates by reference the terms and conditions of this Agreement and
describes one or more items of Equipment and specific terms and conditions with
respect thereto.

      "Event of Default" shall have the meaning ascribed to such term in Section
7 of this Agreement.

      "Loan Agreement" shall mean the approval letter dated August 28, 2002 from
Lender to Borrower (the Approval Letter ) and this Agreement, as supplemented by
the applicable Equipment Schedules which incorporates the terms and conditions
of the Approval Letter and this Agreement, including all exhibits, addenda,
schedules, certificates, riders and all other documents and instruments executed
and delivered in connection therewith.

      "Note" shall mean a promissory note of Borrower in favor of Lender
evidencing Borrower's obligations to Lender with respect to the Loan Agreement.

      "Obligations" shall mean all liabilities in connection with the Loan
Agreement, absolute or contingent, joint, several or independent, of now or
hereafter existing, due or to become due to, or held or to be held by, Lender
for its

                                                         Initial /s/ HGM/ /s/ KH
                                                                 ---------------

                                  Page 1 of 13
<PAGE>
                       MASTER LOAN AND SECURITY AGREEMENT

own account or as agent for another or others, whether created directly or
acquired by assignment or otherwise and howsoever evidenced, including, without
limitation, the Loan Agreement, and all interest, taxes, fees, charges, expenses
and Attorneys' Fees and Expenses chargeable to Borrower or incurred by Lender
under the Loan Agreement, or any other document or instrument delivered in
connection herewith.

      "Person" shall mean any individual, partnership, joint venture, firm,
corporation, association, trust, or other enterprise or any government or
political subdivision or any agency, department or instrumentality thereof.

      "Security Deposit" with respect to each item of Equipment shall have the
meaning assigned to such term in the Equipment Schedule applicable to such item
of Equipment.

      "UCC" shall mean the Uniform Commercial Code as enacted in the
Commonwealth of Virginia.

      2. LOAN; CONDITIONS; SECURITY INTEREST.

      (a) Loan. Lender shall, subject to compliance by Borrower with the terms
and conditions hereof, make advances to Borrow from time to time in an amount up
to $6,500,000 for the purchase of Equipment and as set forth in the Approval
Letter, other soft expenses related to such Equipment for the internal use of
Borrower.

      (b) Conditions. Lender shall not be obligated to make any loan hereunder
unless: (i) the Note or Equipment Schedule evidencing such loan shall have been
duly executed and delivered to Lender; (ii) Borrower shall have executed and
delivered to Lender the Equipment Schedule describing the Collateral and stating
the location thereof; (iii) Lender shall have received evidence that insurance
has been obtained in accordance with the provisions hereof; (iv) Lender shall
have received any and all third party consents, waivers or releases deemed
necessary or desirable in Lender's reasonable judgment in connection with the
loan and the Collateral being financed, including without limitation Uniform
Commercial Code lien releases and the consent and waiver, in form and substance
satisfactory to Lender, of each and every realty owner, landlord and mortgagee
holding an interest in or encumbrance on the real property where any of the
Collateral is to be located; (v) all filings, recordings and other actions
deemed necessary or desirable by Lender in order to establish, protect, preserve
and perfect its security interest in the Collateral being financed by such loan
as a valid perfected first priority security interest shall have been duly
effected, including without limitation the filing of financing statements and
the recordation of landlord (owners) and/or mortgagee waivers or disclaimers,
all in form and substance satisfactory to Lender, and all fees, taxes and other
charges relating to such filings and recordings shall have been paid by
Borrower; (vi) the representations and warranties of Borrower hereunder and
under the Loan Agreement shall be true and correct in all respects on and as of
the date of the making of any advance hereunder with the same effect as if made
on and as of such date; (vii) in the sole and good faith judgment of Lender,
there shall have been no material adverse change in the financial condition,
business, operations, prospects, product development, technology, or business or
contractual relations with third parties of Borrower from the date hereof and no
change or event shall have occurred which would impair the ability of Borrower
to perform its obligations hereunder or under any of the other Financing
Agreements to which it is a party or of Lender to enforce the Obligations or
realize upon the Collateral; (viii) all documents and agreements shall be
satisfactory to Lender and its attorneys; (ix) Lender shall have received, in
form and substance satisfactory to Lender, such other documents as Lender shall
require; and (x) no Default, Event of Default, or circumstance or facts that
would (with the giving of notice or the passage of time or both) become a
Default or Event of Default hereunder shall have occurred and be continuing.

      (c) Security Interest. As security for the due and punctual payment of any
and all of the present and future Obligations of Borrower to Lender, Borrower
hereby (i) grants to Lender with respect to each Loan Agreement and for the full
amount of all Obligations, a security interest in all of the Collateral and all
collateral securing any other lease or security agreement between Borrower and
Lender, whether now in existence or hereafter entered into, to the extent the
Obligations herein remain unsatisfied, and (ii) assigns to Lender all of its
rights, title and interest in surplus money to which Borrower may be entitled
upon the sale of all such Collateral, to the extent the Obligations herein
remain unsatisfied. The extent to which Lender's security interest in any item
of Collateral shall be entitled to purchase money priority shall be determined
by reference to the unpaid principal balance of any Note evidencing the
financing of the purchase price of such item of Equipment.

      3. ACCEPTANCE OF EQUIPMENT. The Equipment is to be delivered and installed
at the location specified or referred to in the applicable Equipment Schedule.
The Equipment shall be deemed to have been accepted by Borrower for all purposes
under this Agreement upon Borrower's execution of an Equipment Schedule (the
"Acceptance Date"). Lender shall not be liable or responsible for any failure or
delay in the delivery of the Equipment to Borrower for whatever reason.

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<PAGE>
                       MASTER LOAN AND SECURITY AGREEMENT

      4. TERM; INTEREST RATE; PRINCIPAL AND INTEREST; PREPAYMENT; LATE CHARGES.

      (a) Term and Interest. The term and interest for any advance shall be as
specified in the applicable Equipment Schedule and in accordance with the
Approval Letter.

      (b) Payment Dates. Principal and interest payments for each advance shall
be paid monthly, in advance in accordance with the schedule set forth in the
applicable Equipment Schedule. The first and last monthly payments shall be made
on the day the funds are advanced to Borrower.

      (c) Prepayment. Provided that an Event of Default has not occurred or is
continuing to occur, and the Borrower has timely paid at least the first twelve
(12) monthly payments due under the Loan Agreement, Borrower shall have the
ability under the circumstances of a corporate merger or acquisition resulting
in a change of control of at least 50% of the outstanding voting stock, upon at
least (30) days prior written notice to Lender, to prepay any and all amounts
outstanding under the Loan Agreement on the periodic installment due date
designated in such notice by paying to the Lender, the sum of (i) the then
outstanding principal balance plus interest and all other amounts owing under
the Loan Agreement (calculated on a simple interest basis) plus (ii) a premium
of 5% if such prepayment shall occur in Year 2, a premium of 4% if such
prepayment shall occur in Year 3 and a premium of 3% if such prepayment shall
occur in Year 4 and thereafter. The premium applicable will be calculated on the
then outstanding principal balance. Year 1 will mean the period consisting of
the 1st through the 12th installments under the Loan Agreement and subsequent
years will refer to the subsequent twelve monthly payment periods. Principal and
interest payments shall be in the amounts and shall be due and payable as set
forth in the applicable Equipment Schedule.

      (d) Late Charge. If any payment of principal or interest or other amount
payable hereunder shall not be paid within 5 days of the date when due, Borrower
shall pay as an administrative and late charge an amount equal to 4% of the
amount of any such overdue payment. In addition, Borrower shall pay overdue
interest on any delinquent payment or other amounts due under the Loan Agreement
(by reason of acceleration or otherwise) from the due date until paid at the
rate of one percent (1.0%) per month or the maximum amount permitted by
applicable law, whichever is lower. All payments to be made to Lender shall be
made to Lender in immediately available funds at the address shown above, or at
such other place, as Lender shall specify in writing.

      5. REPRESENTATIONS, WARRANTIES AND COVENANTS. Borrower hereby represents
and warrants to and covenants with Lender (provided that if Borrower is an
individual or sole proprietorship, the representations, warranties and covenants
relating to corporate status shall not apply) that, as of the date hereof and
for so long as any Obligations shall remain outstanding:

      (a) Borrower is duly organized and is existing in good standing under the
laws of its jurisdiction of organization and is duly qualified and in good
standing in those jurisdictions where the conduct of its business or the
ownership of its properties requires qualification;

      (b) Borrower has the power and authority to own the Collateral, to enter
into and perform this Agreement and any other document or instrument delivered
in connection herewith and to incur the Obligations;

      (c) Borrower's chief executive office is located at the address set forth
above;

      (d) Borrower does not utilize, and has not in the last five years
utilized, any trade names in the conduct of its business except as set forth on
Schedule 1 hereto;

      (e) Borrower has not changed its name, been the surviving entity in a
merger, acquired any business or changed the location of its chief executive
office within the previous five years, except as set forth on Schedule 2 hereto;

      (f) Neither the execution, delivery or performance by Borrower of the Loan
Agreement nor compliance by it with the terms and provisions hereof, nor the
consummation of the transactions contemplated herein, (i) will contravene any
applicable provision of any law, statute, rule or regulation, or any order,
writ, injunction or decree of any court or governmental instrumentality, (ii)
will conflict or be inconsistent with or result in any breach of any of the
terms, covenants, conditions or provisions of, or constitute a default under, or
result in any lien upon any property, pursuant to the terms of any indenture,
mortgage, deed of trust, loan agreement or any other material agreement or
instrument to which Borrower is a party or by which it or any of its property or
assets are bound or to which it may be subject or (iii) will violate any
provision of its Certificate of Incorporation or By-Laws, or other governance
documents;

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                                  Page 3 of 13
<PAGE>
                       MASTER LOAN AND SECURITY AGREEMENT

      (g) The Loan Agreement, the Note and any document or instrument delivered
in connection herewith and the transactions contemplated hereby or thereby are
duly authorized, executed and delivered, and the Loan Agreement, the Note and
such other documents and instruments constitute valid and legally binding
obligations of Borrower and are enforceable against Borrower in accordance with
their respective terms;

      (h) No order, consent, approval, license, authorization, or validation of,
or filing (except with respect to UCC filings), recording or registration with,
or exemption by any governmental or public body or authority, or any subdivision
thereof, is required to authorize or required in connection with (i) the grant
by Borrower of the security interest in connection with the Loan Agreement, (ii)
the execution, delivery and performance of the Loan Agreement, (iii) the
legality, validity, binding effect or enforceability of the Loan Agreement or
(iv) the perfection or maintenance of the aforementioned lien and security
interest;

      (i) Borrower has filed all federal, state and local tax returns and other
reports it is required to file, has paid or made adequate provision for payment
of all such taxes, assessments and other governmental charges, and shall pay or
deposit promptly when due all sales, use, excise, personal property, income,
withholding, corporate, franchise and other taxes, assessments and governmental
charges upon or relating to the manufacture, purchase, ownership, maintenance,
modification, delivery, installation, possession, condition, use, acceptance,
rejection, operation or return of the Equipment and, upon request by Lender,
Borrower will submit to Lender proof satisfactory to Lender that such payments
and/or deposits have been made;

      (j) There are no pending or threatened actions or proceedings before any
court or administrative agency, an unfavorable resolution of which could have a
material adverse effect on Borrower's financial condition or operations;

      (k) No representation, warranty or statement by Borrower contained in the
Loan Agreement or in any certificate or other document furnished or to be
furnished by Borrower pursuant to the Loan Agreement contains or at the time of
delivery shall contain any untrue statement of material fact, or omits, or shall
omit at the time of delivery, to state a material fact necessary to make it not
misleading;

      (1) All financial statements delivered and to be delivered by Borrower to
Lender in connection with the execution and delivery of the Loan Agreement are
true and correct in all material respects and have been prepared in accordance
with generally accepted accounting principles, and at all times since the date
of the most recent financial statements, there has been no material change in
Borrower's financial affairs or business operations. Borrower shall furnish
Lender: (i) within 120 days after the last day of each fiscal year of Borrower,
a financial statement including a balance sheet, income statement, statement of
shareholders equity and statement of cash flows, each prepared in accordance
with generally accepted accounting principles consistently applied with a report
signed by an independent certified public accountant satisfactory to Lender;
(ii) within 45 days after the close of each quarter of each fiscal year of
Borrower, a financial statement including a balance sheet, income statement and
statement of cash flows, each prepared by Borrower in accordance with generally
accepted accounting principles consistently applied by Borrower and certified by
the chief financial officer of Borrower; (iii) promptly upon the request of
Lender, such tax returns or financial statements regarding any guarantor, if
any, of the Obligations of Borrower as Lender may reasonably request from time
to time; (iv) promptly upon request of Lender, in form satisfactory to Lender,
such other and additional information as Lender may reasonably request from time
to time, and; (v) promptly inform Lender of any Defaults (defined below) or any
events or changes in the financial condition of Borrower occurring since the
date of the last financial statements of Borrower delivered to Lender which,
individually or cumulatively, when viewed in light of prior financial
statements, may result in a material adverse change in the financial condition
of Borrower;

      (m) Borrower shall permit Lender, through its authorized attorneys,
accountants and representatives, to inspect and examine the Equipment and the
books, accounts, records, ledgers and assets of every kind and description of
Borrower with respect thereto at all reasonable times; provided, however, that
the failure of Lender to inspect the Equipment or to inform Borrower of any
noncompliance shall not relieve Borrower of any of its Obligations hereunder;

      (n) Borrower is the owner of the Equipment free and clear of all rights,
title, security interests, encumbrances or liens of any other party, will defend
the Equipment against all claims and demands of all persons at any time claiming
any interest therein and shall deliver to Lender any and all evidence of
ownership of, and certificates of title to, any and all of the Equipment;

      (o) The Equipment is personal property and not a fixture under the law of
the jurisdiction in which the Equipment is located even though the Equipment may
hereafter become attached or affixed to real property;

      (p) Each site where Equipment is located, if not owned by Borrower, is
leased by Borrower pursuant to a valid lease or rental agreement which permits
the possession, use and operation of the Equipment at such location;

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                                  Page 4 of 13
<PAGE>
                       MASTER LOAN AND SECURITY AGREEMENT

      (q) Borrower shall provide Lender with disclaimers and waivers from
landlords, mortgagees and other persons holding any interest or claim in and to
any premises where Equipment is located, acceptable in all respects to Lender,
which may be necessary or advisable in the sole discretion of Lender to confirm
that the first priority security interest and rights of Lender in the Equipment
are and will remain valid and superior against all other parties;

      (r) The Equipment is in the possession of Borrower at the location(s)
specified in the applicable Equipment Schedule, and shall not be removed from
such location without 30 days written notice to Lender and the subsequent prior
written consent of Lender, which consent shall not be unreasonably withheld and
shall in any event be conditioned upon Borrower having completed all
notifications, filings, recordings, and other actions in such new location as
Lender may require to protect and perfect Lender's interests in the Collateral;

      (s) Borrower shall not, without the prior written consent of Lender, sell,
offer to sell, lease, rent, hire or in any other manner dispose, transfer or
surrender use and possession of any Equipment;

      (t) Borrower will not, directly or indirectly, create, incur or permit to
exist any lien, encumbrance, mortgage, pledge, attachment or security interest
on or with respect to the Equipment other than in connection with the execution
and delivery of the Loan Agreement;

      (u) Borrower shall permit each item of Equipment to be used only within
the continental United States by qualified personnel solely for business
purposes and the purpose for which it was designed and, at its sole expense,
shall service, repair, overhaul and maintain each item of Equipment in the same
condition as when received, ordinary wear and tear excepted, in good operating
order, consistent with prudent industry practice (but, in no event less than the
same extent to which Borrower maintains other similar equipment in the prudent
management of its assets and properties) and in compliance with all applicable
laws, ordinances, regulations, and conditions of all insurance policies required
to be maintained by Borrower under the Loan Agreement and all manuals, orders,
recommendations, instructions and other written requirements as to the repair
and maintenance of such item of Equipment issued at any time by the vendor
and/or manufacturer thereof;

      (v) If any item of Equipment does not comply with the requirements of the
Loan Agreement, Borrower shall bring such Equipment into compliance with the
provisions hereof; and Borrower shall not use any Equipment, nor allow the same
to be used, for any unlawful purpose;

      (w) Borrower acknowledges that Lender has not selected, manufactured or
supplied the Equipment to Borrower and has acquired any Equipment subject hereto
solely in connection with this Loan Agreement and Borrower has received and
approved the terms of any purchase order or agreement with respect to the
Equipment; and

      (x) Borrower has all permits, licenses and other authorizations which are
required with respect to its business under Environmental Laws (as defined
below) and is in compliance with all terms and conditions of such permits,
licenses and other authorizations, including all limitations, restrictions,
standards, prohibitions, requirements, obligations, schedules and timetables.
The Borrower is not presently in violation of any Environmental Laws.
"Environmental Laws" shall mean any Federal, state or local law relating to
releases or threatened releases of Hazardous Substances; the manufacture,
handling, transport, use, treatment, storage or disposal of Hazardous Substances
or materials containing Hazardous Substances; or otherwise relating to pollution
of the environment or the protection of human health. "Hazardous Substances"
shall mean substances or materials which contain substances defined in or
regulated as toxic or hazardous materials, chemicals, substances, waste or
pollutants under any present or future Federal statutes and their state
counterparts, as well as any implementing regulations as amended from time to
time and as interpreted by administering agencies.

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                                  Page 5 of 13
<PAGE>
                       MASTER LOAN AND SECURITY AGREEMENT

      6. RISK OF LOSS AND DAMAGE; INSURANCE. Borrower assumes all risk of loss,
damage or destruction to the Equipment from whatever cause and for whatever
reason. If all or a potion of an item of Equipment shall become lost, stolen,
destroyed, damaged beyond repair or rendered permanently unfit for use for any
reason, or in the event of any condemnation, confiscation, theft or seizure or
requisition of title to or use of such item of Equipment, Borrower shall
immediately pay to Lender an amount equal to the outstanding principal balance
of and accrued and unpaid interest on any Note with respect to such Equipment,
less the net amount of the recovery, if any, received by Lender from insurance
on the Equipment. For so long as any Obligations shall remain outstanding,
Borrower shall procure and maintain insurance in such amounts and with such
coverages, and upon such terms and with such companies, as Lender may reasonably
approve, consistent with normal/prudent industry practices, at Borrower's
expense; provided, however, that in no event shall such insurance be less than
the following coverages and amounts: (a) worker's compensation and Employer's
Liability Insurance, in the full statutory amounts provided by law; (b)
Comprehensive General Liability Insurance including product/completed operations
and contractual liability coverage, with minimum limits on a per occurrence
basis, as reasonably required by Lender, and Combined Single Limit Bodily Injury
and Property Damage on an aggregate basis, as reasonably required by Lender or,
in either case, as otherwise specified in any Equipment Schedule hereto; and (c)
All Risk Physical Damage Insurance, including earthquake and flood, on each item
of Equipment, in an amount not less than the greater of (i) the outstanding
principal balance owing under any Note with respect to such Equipment; or (ii)
its full replacement value. Borrower shall cause Lender to be included as an
additional insured on each such Comprehensive General Liability Insurance
policy. On each such All Risk Physical Damage Insurance policy Lender shall be
named as loss payee. Such policies shall be endorsed to provide that the
coverage afforded to Lender shall not be rescinded, impaired or invalidated by
any act or neglect of Borrower. Borrower agrees to waive Borrower's rights and
its insurance carrier's rights of subrogation against Lender for any and all
loss or damage. In addition to the foregoing minimum insurance coverage,
Borrower shall procure and maintain such other insurance coverage as Lender may
reasonably require, consistent with normal/prudent industry practices. All
policies shall be endorsed or contain a clause requiring the insurer to furnish
Lender with at least 30 days prior written notice of any material change,
cancellation or non-renewal of coverage. Upon execution of this Agreement, and
thereafter, 30 days prior to the expiration of each insurance policy required
hereunder, Borrower shall furnish Lender with a certificate of insurance or
other evidence satisfactory to Lender that the insurance coverages required
under such policy are and will continue in effect, provided, however, that
Lender shall be under no duty either to ascertain the existence of or to examine
such insurance coverage or to advise Borrower in the event such insurance
coverage should not comply with the requirements hereof. If Borrower shall at
any time or times hereafter fail to obtain and/or maintain any of the policies
of insurance required herein, or fail to pay any premium in whole or in part
relating to any such policies, Lender may, but shall not be obligated to, obtain
and/or cause to be maintained insurance coverage with respect to the Collateral,
including, at Lender's option, the coverage provided by all or any of the
policies of Borrower and pay all or any part of the premium therefor, without
waiving any Event of Default by Borrower, and any sums so disbursed by Lender
shall be additional Obligations of Borrower to Lender payable on demand. Lender
shall have the right to settle and compromise any and all claims under any of
the All Risk Physical Damage policies required to be maintained by Borrower
hereunder and Borrower hereby appoints Lender as its attorney-in-fact, with
power to demand, receive and receipt for all monies payable thereunder, to
execute in the name of Borrower or Lender or both any proof of loss, notice,
draft or other instruments in connection with such policies or any loss
thereunder and generally to do and perform any and all acts as Borrower, but for
this appointment, might or could perform.

      7. EVENTS OF DEFAULT. An "Event of Default" under this Agreement shall be
deemed to have occurred upon the occurrence or existence of any one or more of
the following events or conditions (each a "Default") and after the giving of
any required notice or the passage of any required period of time (or both)
specified below with respect to such Default: (a) Borrower shall fail to make
any payment due under any Note or as required under the Loan Agreement within 5
days of its due date; or (b) Borrower shall fail to obtain or maintain any of
the insurance required under the Loan Agreement; or (c) Borrower shall remove,
sell, transfer, encumber, or part with possession of any Equipment; (d) Borrower
shall fail to perform or observe any other covenant, condition or agreement
under the Loan Agreement, and such failure shall continue for 20 days after
notice thereof to Borrower; or (e) Borrower shall default in the payment or
performance of any Obligation owing to Lender, and such default shall continue
for 20 days after notice thereof to Borrower; or (f) any representation or
warranty made by Borrower herein or in any certificate, agreement, statement or
document heretofore or hereafter furnished Lender, including without limitation
any financial information disclosed to Lender, shall prove to be false or
incorrect in any material respect; or (g) the commencement of any bankruptcy,
insolvency, arrangement, reorganization, receivership, liquidation or other
similar proceeding by or against Borrower or any of its properties or
businesses, or the appointment of a trustee, receiver, liquidator or custodian
for Borrower or any of its properties or businesses, or if Borrower suffers the
entry of an order for relief under Title 11 of the United States Code; or (h)
the making by Borrower of a general assignment or deed of trust for the benefit
of creditors; or (i) Borrower shall default in any payment or other material
obligation to any other lender and such lender has accelerated the debt in
accordance with its terms; or (j) Borrower shall, without the prior written
consent of Lender, (i) merge with or consolidate into any other entity (other
than an acquisition by Borrower of the capital stock or assets of another entity
where (A) the aggregate cash consideration paid or to be paid in connection with
such acquisition does not exceed $1,500,000, and (B) the aggregate number of
shares of Borrowers capital stock issued or to be issued in connection with such
acquisition does not exceed (on a common stock as-if-converted basis) 20% of the
aggregate capital stock of

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                                  Page 6 of 13
<PAGE>
                       MASTER LOAN AND SECURITY AGREEMENT

Borrower at the time of such transaction), if the resulting entity's overall
financial condition after the merger or consolidation is worse than the overall
financial condition of Borrower before the merger or consolidation in Lender's
sole but good faith opinion, or (ii) sell all or substantially all of its assets
or (iii) in any manner terminate its existence; or (k) if Borrower is a
privately held corporation and without the prior written consent of Lender, more
than 50% of Borrower's voting capital stock, or effective control of Borrower's
voting capital stock, issued and outstanding from time to time, is not retained
by the holders of such stock on the date the Loan Agreement is executed; or (1)
if Borrower is a publicly held corporation and without the prior written consent
of Lender, there shall be a change in the ownership of Borrower's stock such
that Borrower is no longer subject to the reporting requirements of the
Securities Exchange Act of 1934 or no longer has a class of equity securities
registered under Section 12 of the Securities Act of 1933; or (m) Lender shall
determine that there has been a material adverse change in the financial
condition or business operations of Borrower since the date of the execution of
the Loan Agreement, or that Borrower's ability to perform its obligations is
materially impaired; or (n) if Borrower leases the premises where any Equipment
is located, a breach by Borrower of any such lease and the commencement of an
action by the landlord to evict Borrower or to repossess the premises; or (o)
any event or condition set forth in subsections (e) through (m) of this Section
7 shall occur with respect to any guarantor or other person liable or
responsible, in whole or in part, for payment or performance of any Obligations.
Borrower shall promptly notify Lender of the occurrence of any Event of Default
or the occurrence or existence of any event or condition, which, upon the giving
of notice or lapse of time, or both, would constitute an Event of Default.

      8. RIGHTS AND REMEDIES; ACCELERATION. (a) Upon the occurrence of an Event
of Default, Lender shall have all of the rights and remedies enumerated herein
(all of which are cumulative and not exclusive of any other right or remedy
available to Lender) and Lender may, at its sole option and discretion, exercise
one or more of the following remedies with respect to any or all of the
Collateral: (i) by written notice to Borrower, terminate any or all Loan
Agreements as such notice shall specify, and, with respect to such terminated
Loan Agreements, declare immediately due and payable and recover from Borrower,
as liquidated damages for loss of Lender's bargain and not as a penalty, an
amount equal to the aggregate of all unpaid periodic installment payments and
other sums due under Loan Agreements to the date of default plus the charges set
forth in Section 4 hereof, if any, plus an amount equal to the outstanding
principal balances of and accrued and unpaid interest on any of the Notes with
respect to the Loan Agreements, (ii) Lender may declare, at its option, all or
any part of the Obligations immediately due and payable, without demand, notice
of intention to accelerate, notice of acceleration, notice of nonpayment,
presentment, protest, notice of dishonor, or any other notice whatsoever, all of
which are hereby waived by borrower and any endorser, guarantor, surety or other
party liable in any capacity for any of the Obligations; (iii) cause Borrower to
promptly ship, with insurance and freight prepaid by Borrower, any or all
Equipment to such location as Lender may reasonably designate, or Lender, at its
option, may enter upon the premises where the Equipment is located and take
immediate possession of and remove the same by summary proceedings or otherwise,
all without liability to Lender for or by reason of damage to property or such
entry or taking possession except for Lender's gross negligence or willful
misconduct; (iv) sell any or all Collateral at public or private sale or
otherwise dispose of, hold, use, operate, lease to others or keep idle the
Equipment, all as Lender in its sole discretion may determine and all free and
clear of any rights of Borrower; (v) remedy such default, including making
repairs or modifications to the Equipment, for the account and expense of
Borrower, and Borrower agrees to reimburse Lender for all of Lender's reasonable
costs and expenses; (vi) apply any security Deposit or other cash collateral or
sale or remarketing proceeds of the Equipment at any time to reduce any amounts
due to Lender, or (vii) exercise any other right or remedy which may be
available to Lender under applicable law, or proceed by appropriate court action
to enforce the terms hereof or to recover damages for the breach hereof,
including Attorneys' Fees and Expenses. Any notice required to be given by
Lender of a sale or other disposition or other intended action which is made in
accordance with the terms of the Loan Agreement at least ten (10) days prior to
such proposed action, shall constitute fair and reasonable notice to Borrower of
any such action. Lender shall be liable to Borrower only for its gross
negligence or willful misconduct in failing to comply with any applicable law
imposing duties upon Lender; Lender's liability for any such failure shall be
limited to the actual loss suffered by Borrower directly resulting from such
failure; and in no event shall Lender have any liability to Borrower for
consequential, punitive or exemplary damages. No remedy referred to in this
Section 8 shall be exclusive, but each shall be cumulative and in addition to
any other remedy referred to above or otherwise available to Lender at law or in
equity.

      (b) The exercise or pursuit by Lender of any one or more of such remedies
shall not preclude the simultaneous or later exercise or pursuit by Lender of
any or all such other remedies, and all remedies hereunder shall survive
termination of the Loan Agreement. In the event Lender takes possession and
disposes of the Collateral, the proceeds of any such disposition shall be
applied in the following order: (1) to all of Lender's costs, charges and
expenses incurred in taking, removing, holding, repairing and selling or leasing
the Equipment; (2) to pay the Lender the remaining amount of any Obligations
owed to Lender and (3) the balance, if any, to Borrower. A termination shall
occur only upon written notice by Lender and only with respect to such
Equipment, as Lender shall specify in such notice. Termination under this
Section 8 shall not affect Borrower's duty to perform Borrower's Obligations
under the Loan Agreement in full. Borrower agrees to reimburse Lender on demand
for any and all reasonable costs and expenses incurred by Lender in enforcing
its rights and remedies hereunder following the occurrence of an Event of
Default, including, without limitation, Attorneys' Fees and

                                                         Initial /s/ HGM/ /s/ KH
                                                                 ---------------
                                  Page 7 of 13

<PAGE>
                       MASTER LOAN AND SECURITY AGREEMENT

Expenses, and the reasonable costs of repossession, storage, insuring,
reletting, selling and disposing of any and all Equipment.

      9. INDEMNITY. (a) Borrower agrees to indemnify, reimburse and hold Lender
and its successors, Affiliates, assigns, officers, directors, employees, agents
and servants (hereinafter in this Section 9 referred to individually as
"Indemnitee", and collectively as "Indemnitees") harmless from any and all
liabilities, obligations, damages, injuries, penalties, claims, demands,
actions, suits, judgments and any and all costs, expenses or disbursements,
including Attorneys' Fees and Expenses of whatsoever kind and nature imposed on,
asserted against or incurred by any of the Indemnitees in any way relating to or
arising out of the Loan Agreement or any other document executed in connection
herewith or therewith or in any other way connected with the administration of
the transactions contemplated hereby or thereby or the enforcement of any of the
terms of, or the preservation of any rights under any thereof, or in any way
relating to or arising out of the manufacture, ownership, ordering, purchase,
delivery, control, acceptance, lease, financing, possession, operation,
condition, sale, return or other disposition, or use of the Equipment
(including, without limitation, latent or other defects, whether or not
discoverable), the violation of the laws of any country, state or other
governmental body or unit, any tort (including, without limitation, claims
arising or imposed under the doctrine of strict liability, or for or on account
of injury to or the death of any Person (including any Indemnitee), or property
damage), or contract claim, or any claim based on patent, trademark or copyright
infringement or any obligation or liability to the manufacturer or supplier of
the Equipment under any Supply Contracts (referenced in the Equipment Schedule),
including purchase orders issued by Borrower or Lender or assigned to Lender,
provided, however, that no Indemnitee shall be indemnified pursuant to this
Section 9 for losses, damages or liabilities to the extent caused by the gross
negligence or willful misconduct of such Indemnitee. Borrower agrees that upon
written notice by any Indemnitee of the assertion of such a liability,
obligation, damage, injury, penalty, claim, demand, action, suit or judgment,
Borrower shall assume full responsibility for the defense thereof. Each
Indemnitee agrees to use its best efforts to promptly notify Borrower of any
such assertion of which such Indemnitee has knowledge and agrees to use
reasonable efforts to cooperate with Borrower respecting the defense of any
matter indemnified hereunder except insofar and to the extent that Lender's
interests with respect thereto may be adverse to Borrower's as determined by
Lender in Lenders sole discretion.

      (b) Without limiting the application of Section 9(a) hereof, Borrower
agrees to pay, or reimburse Lender for any and all reasonable fees, costs and
expenses (including Attorneys' Fees and Expenses) of whatever kind or nature
incurred in connection with the creation, preservation or protection of Lender's
liens on, and security interest in, the Collateral, including, without
limitation, all fees and taxes in connection with the recording or filing of
instruments and documents in public offices, payment or discharge of any taxes
or liens upon or in respect of the Collateral, premiums for insurance with
respect to the Collateral and all other fees, costs and expenses in connection
with protecting, maintaining or preserving the Collateral and Lender's interest
therein, whether through judicial proceedings or otherwise, or in defending or
prosecuting any actions, suits or proceedings arising out of or relating to the
Collateral.

      (c) Borrower shall, at its sole cost and expense, protect, defend,
indemnify, release and hold harmless the Indemnitees from and against any and
all Losses imposed upon or incurred by or asserted against any Indemnitees, and
arising out of or in any way relating to any one or more of the following,
except to the extent by the gross negligence or willful misconduct of any
Indemnitee: (i) any presence of Hazardous Substances in, on, above or under
Borrower's leased or owned real property (the "Property"); (ii) any past,
present or threatened Release of Hazardous Substances in, on, above, under or
from the Property; or (iii) any past or present violation of any Environmental
Laws. The term "Release" of any Hazardous Substance includes, but is not limited
to, any release, deposit, discharge, emission, leaking, spilling, seeping,
migrating, injecting, pumping, pouring, emptying, escaping, dumping, disposing
or other movement of Hazardous Substances. The term "Losses" includes any and
all claims, suits, liabilities (including, without limitation, strict
liabilities), actions, proceedings, obligations, debts, damages, losses, costs,
expenses, diminutions in value, fines, penalties, charges, fees, expenses,
judgments, awards, amounts paid in settlement, costs of remediating a Hazardous
Substance (whether or not performed voluntarily), engineers' fees, environmental
consultants' fees, and costs of investigation (including, but not limited to
sampling, testing and analysis of soil, water, air, building materials and other
materials and substances whether solid, liquid or gas) or punitive damages, of
whatever kind or nature (including, but not limited to Attorneys' Fees and
Expenses).

      (d) Without limiting the application of Section 9(a) or (b), or (c)
hereof, Borrower agrees to pay, indemnify and hold each Indemnitee harmless from
and against any loss, costs, damages and expenses (including Attorneys' Fees and
Expenses) which such Indemnitee may suffer, expend or incur in consequence of or
growing out of any misrepresentation or omission of a material fact by Borrower
in the Loan Agreement or in any writing contemplated by or made or delivered
pursuant to or in connection with the Loan Agreement.

      (e) If and to the extent that the obligations of Borrower under this
Section 9 are unenforceable for any reason, Borrower hereby agrees to make the
maximum contribution to the payment and satisfaction of such obligations which
is permissible under applicable law.

                                                         Initial /s/ HGM/ /s/ KH
                                                                 ---------------

                                  Page 8 of 13
<PAGE>
                       MASTER LOAN AND SECURITY AGREEMENT

      10. MAINTENANCE; INSPECTION. During the term of the Loan Agreement,
Borrower shall, unless Lender shall otherwise consent in writing: (a) maintain
conspicuously on any Equipment such labels, plates, decals or other markings as
Lender may reasonably require, stating that Lender has a security interest in
such Equipment; (b) furnish to Lender such information concerning the condition,
location, use and operation of the Equipment as Lender may request; (c) permit
any person designated by Lender to visit and inspect any Equipment and any
records maintained in connection therewith, provided, however, that the failure
of Lender to inspect the Equipment or to inform Borrower of any noncompliance
shall not relieve Borrower of any of its obligations hereunder; and (d) make no
additions, alterations, modifications or improvements (collectively,
"Improvements") to any item of Equipment that are not readily removable without
causing material damage to such item of Equipment or which will cause the value,
utility or useful life of such item of Equipment to materially decline. If any
such Improvement is made and cannot be removed without causing material damage
or decline in value, utility or useful life (a "Non-Severable Improvement"),
then Borrower warrants that such Non-Severable Improvement shall immediately
become subject to Lender's security interest upon being installed and shall be
free and clear of all liens and encumbrances and shall become Equipment subject
to all of the terms and conditions of the Loan Agreement.

      11. FURTHER ASSURANCES. Borrower shall promptly execute and deliver to
Lender such further documents and take such further action as Lender may
reasonably require in order to more effectively carry out the intent and purpose
of the Loan Agreement. Borrower shall execute and deliver to Lender upon
Lender's request any and all schedules, forms and other reports and information
as Lender may deem necessary or appropriate to respond to requirements or
regulations imposed by any governmental authorities or to comply with the
provisions of the law of any jurisdiction in which Borrower may then be
conducting business or in which any of the Equipment may be located. Borrower
authorizes Lender to file financing statements and amendments thereto describing
the Collateral and containing any other information required by the applicable
Uniform Commercial Code.

Borrower shall execute and deliver to Lender upon Lender's request such further
and additional documents, instruments and assurances as Lender deems necessary
to acknowledge and confirm, for the benefit of Lender or any assignee or
transferee of any of Lender's rights, title and interests hereunder in
accordance with Section 12 hereof (an "Assignee"), all of the terms and
conditions of all or any part of the Loan Agreement and Lender's or Assignee's
rights with respect thereto, and Borrower's compliance with all of the terms and
provisions thereof.

      12. ASSIGNMENT. The provisions of the Loan Agreement shall be binding upon
and shall inure to the benefit of the heirs, administrators, successors and
assigns of Lender and Borrower, provided, however, Borrower may not assign any
of its rights, transfer any interest in the Equipment or delegate any of its
obligations under the Loan Agreement without the prior written consent of Lender
in its sole discretion. Lender may, from time to time, absolutely or as
security, without notice to Borrower, sell, assign, transfer, participate,
pledge or otherwise dispose of all or any part of a Loan Agreement, the
Obligations and/or the Collateral therefor, subject to the rights of Borrower
under the Loan Agreement for the use and possession of the Equipment. In such
event, each and every immediate and successive Assignee shall have the right to
enforce the Loan Agreement with respect to those Obligations and/or Collateral
transferred to the Assignee, by legal action or otherwise, for its own benefit
as fully as if such Assignee were herein by name specifically given such rights.
Borrower agrees that the rights of any such Assignee hereunder or with respect
to the related Obligations, shall not be subject to any defense, set off or
counterclaim that Borrower may assert or claim against Lender, and that any such
Assignee shall have all of Lender's rights hereunder but none of Lender's
obligations. Lender shall have an unimpaired right to enforce the Loan Agreement
for its benefit with respect to that portion of any Loan Agreement, Obligations
and/or Collateral that Lender has not sold, assigned, pledged or otherwise
transferred.

      13. GOVERNING LAW; THE LOAN AGREEMENT AND THE LEGAL RELATIONS OF THE
PARTIES HERETO SHALL IN ALL RESPECTS BE GOVERNED BY AND CONSTRUED IN ACCORDANCE
WITH THE LAWS OF THE COMMONWEALTH OF VIRGINIA, WITHOUT REGARD TO PRINCIPLES
REGARDING THE CHOICE OF LAW. BORROWER AND LENDER HEREBY CONSENTS AND SUBMITS TO
THE NON-EXCLUSIVE JURISDICTION OF THE COURTS OF THE COMMONWEALTH OF VIRGINIA AND
THE FEDERAL DISTRICT COURT FOR THE COMMONWEALTH OF VIRGINIA FOR THE PURPOSES OF
ANY SUIT, ACTION OR OTHER PROCEEDING ARISING OUT OF ITS OBLIGATIONS UNDER THE
LOAN AGREEMENT, AND EXPRESSLY WAIVE ANY OBJECTIONS THAT IT MAY HAVE TO THE VENUE
OF SUCH COURTS. BORROWER AND LENDER HEREBY EXPRESSLY WAIVES ANY RIGHT TO TRIAL
BY JURY IN ANY ACTION BROUGHT ON OR WITH RESPECT TO THE LOAN AGREEMENT

      14. NOTICES. Any demand or notice required or permitted to be given
hereunder shall be deemed effective (a) when deposited in the United States
mail, and sent by certified mail, return receipt requested, postage prepaid,
addressed to Lender or to Borrower at the addresses set forth herein, or to such
other address as may be hereafter provided by the party to be notified by
written notice complying with the provisions hereof or (b) when transmitted to
Lender or Borrower

                                                         Initial /s/ HGM/ /s/ KH
                                                                 ---------------

                                  Page 9 of 13
<PAGE>
                       MASTER LOAN AND SECURITY AGREEMENT

by facsimile at the respective numbers provided for such purpose; provided, that
such facsimile notice is promptly followed by notice given in accordance with
the immediately preceding subsection (a).

      15. SECURITY DEPOSIT. Lender may, at its option, apply the Security
Deposit, if any is indicated in an Equipment Schedule, to cure any default of
Borrower, whereupon Borrower shall promptly restore such Security Deposit to its
original amount. Lender shall return to Borrower any unapplied Security Deposit,
without interest, upon full payment and performance of Borrower's Obligations
under the Loan Agreement.

      16. MISCELLANEOUS; GENERAL PROVISIONS. The Loan Agreement will not be
binding on Lender or Borrower until accepted and executed by Borrower and Lender
at its executive office in Alexandria, Virginia. All options, powers and rights
granted to Lender hereunder or under any promissory note, guaranty, letter of
credit agreement, depository agreement, instrument, document or other writing
delivered to Lender shall be cumulative and shall be in addition to any other
options, powers or rights which Lender may now or hereafter have under any
applicable law or otherwise. Time is of the essence in the payment and
performance of all of Borrower's and Lender's obligations under the Loan
Agreement. The captions in the Loan Agreement are for convenience only and shall
not define or limit any of the terms thereof.

      Any provisions of the Loan Agreement which are unenforceable in any
jurisdiction shall, as to such jurisdiction, be ineffective to the extent of
such unenforceability without invalidating the remaining provisions hereof, and
any such unenforceability in any jurisdiction shall not render unenforceable
such provisions in any other jurisdiction. To the extent permitted by applicable
law, Borrower hereby waives any provisions of law, which render any provision of
the Loan Agreement unenforceable in any respect.

      BORROWER ACKNOWLEDGES THAT THE TRANSACTION OF WHICH THIS LOAN AGREEMENT IS
A PART IS A COMMERCIAL TRANSACTION AND EXCEPT AS OTHERWISE PROVIDED IN THE LOAN
AGREEMENT BORROWER HEREBY WAIVES, TO THE EXTENT PERMITTED BY APPLICABLE LAW,
NOTICE AND JUDICIAL HEARING IN CONNECTION WITH LENDER'S TAKING POSSESSION OR
LENDER'S DISPOSITION OF ANY OF THE COLLATERAL, INCLUDING, WITHOUT LIMITATION,
ANY AND ALL PRIOR NOTICE AND HEARING FOR ANY PREJUDGMENT REMEDY OR REMEDIES AND
ANY SUCH RIGHT WHICH BORROWER WOULD OTHERWISE HAVE UNDER THE CONSTITUTION OR ANY
STATUTE OF THE UNITED STATES OR OF ANY STATE, INCLUDING, WITHOUT LIMITATION, ITS
RIGHTS TO NOTICE AND HEARING UNDER CHAPTER 903A OF THE VIRGINIA GENERAL
STATUTES.

      THE LOAN AGREEMENT AND ANY OTHER WRITTEN AGREEMENT(S) BETWEEN THE PARTIES
EXECUTED SIMULTANEOUSLY HEREWITH, REPRESENT THE FINAL AGREEMENT BETWEEN THE
PARTIES CONCERNING THE SUBJECT MATTER HEREOF, AND SUPERSEDE AND MAY NOT BE
CONTRADICTED BY ANY PRIOR WRITTEN AGREEMENTS BETWEEN THE PARTIES, INCLUDING,
WITHOUT LIMITATION, PROPOSALS, LETTERS, COMMITMENT LETTERS OR BY ANY PRIOR,
CONTEMPORANEOUS OR SUBSEQUENT ORAL AGREEMENTS BETWEEN THE PARTIES. BORROWER
ACKNOWLEDGES AND CERTIFIES THAT NO SUCH ORAL AGREEMENTS EXIST. THE LOAN
AGREEMENT MAY NOT BE AMENDED, NOR MAY ANY RIGHTS UNDER THE LOAN AGREEMENT BE
WAIVED, EXCEPT BY AN INSTRUMENT IN WRITING SIGNED BY THE PARTY AGAINST WHOM SUCH
AGREEMENT OR WAIVER IS ASSERTED. The failure of Lender at any time or times
hereafter to require strict performance by Borrower of any of the provisions,
warranties, terms and conditions contained in the Loan Agreement or in any other
agreement, guaranty, note, depository agreement, letter of credit, instrument or
document now or at any time or times hereafter executed by Borrower or an
Affiliate of Borrower and delivered to Lender shall not waive, affect or
diminish any right of Lender at any time or times hereafter to demand strict
performance thereof. The Loan Agreement may be executed in any number of
counterparts, each of which shall be deemed to be an original, but all of which
together shall constitute but one and the same instrument. Each reference herein
to "Lender" shall be deemed to include its successors and assigns, and each
reference to "Borrower" and any pronouns referring thereto as used herein shall
be construed in the masculine, feminine, neuter, singular or plural, as the
context may require, and shall be deemed to include the legal representatives,
successors and assigns of Borrower, all of whom shall be bound by the provisions
hereof.

      The Loan Agreement and all related documents, including (a) amendments,
addenda, consents, waivers and modifications which may be executed
contemporaneously or subsequently herewith, (b) documents received by Lender
from the Borrower, and (c) financial statements, certificates and other
information previously or subsequently furnished to Lender, may be reproduced by
Lender by any photographic, photostatic, microfilm, micro-card, miniature
photographic, compact disk reproduction or other similar process and Lender may
destroy any original document so reproduced. Borrower agrees, herein waives all
right to object to the admissibility of such reproduction and stipulates that
any such reproduction shall, to the extent permitted by law, be admissible in
evidence as the original itself in any judicial or administrative proceeding
(whether or not the original itself is in existence and whether or not the
reproduction was made by Lender in the regular course of

                                                         Initial /s/ HGM/ /s/ KH
                                                                 ---------------

                                 Page 10 of 13
<PAGE>
                       MASTER LOAN AND SECURITY AGREEMENT

business) and that any enlargement, facsimile or further reproduction of the
reproduction shall likewise be admissible in evidence.

      17. SURVIVAL. Sections 1, 9, 12, 13, and 16 shall survive and continue in
full force and effect without regard to the payment in full of all Obligations
under the Loan Agreement.

      Executed and delivered by duly authorized representatives of the parties
hereto as of the date set forth below.

LENDER:                                  BORROWER:

OXFORD FINANCE CORPORATION               STRUCTURAL GENOMIX, INC.

By:      /s/ Karl Hefty                  By:      /s/ Herbert G. Mutter

Name:    Karl Hefty                      Name:    Herbert G. Mutter

Title:   VP & Portfolio Manager          Title:   Vice President, Finance

Date:    9/03/02                         Date:    8/28/02

                                                         Initial /s/ HGM/ /s/ KH
                                                                 ---------------
                                 Page 11 of 13
<PAGE>

                       MASTER LOAN AND SECURITY AGREEMENT
--------------------------------------------------------------------------------

                                   SCHEDULE 1

TRADE NAMES

Structural GenomiX, Inc.
SGX
SGX Acquisition Corp.
Prospect Genomics, Inc.
PGI
Protarch, Inc.

                                                         Initial /s/ HGM/ /s/ KH
                                                                 ---------------
                                 Page 12 of 13
<PAGE>

                       MASTER LOAN AND SECURITY AGREEMENT
--------------------------------------------------------------------------------

                                   SCHEDULE 2

NAME CHANGES; CHANGES IN CHIEF EXECUTIVE OFFICE

Name change: from Protarch, Inc. to Structural GenomiX, Inc.

Surving Entity in Merger: SGX Acquisition Corp. was merged with and into
Prospect Genomics, Inc.

Acquired business: Prospect Genomics, Inc.

Prior location of Chief Executive Office: New York, NY

                                                         Initial /s/ HGM/ /s/ KH
                                                                 ---------------
                                 Page 13 of 13
<PAGE>

                              COLLATERAL MIX RIDER
--------------------------------------------------------------------------------

                                       TO
                 MASTER LOAN AND SECURITY AGREEMENT NO. 2081008
                              DATED AUGUST 28, 2002
                                     BETWEEN
                    OXFORD FINANCE CORPORATION (the LENDER)
                                       AND
                     STRUCTURAL GENOMIX, INC. (the BORROWER)

Borrower, Structural GenomiX. Inc., on or before July 30, 2003 shall cause the
composition and mix of Equipment to conform to and meet the following
concentration requirements (hereinafter Concentration Requirement ) for each
class of Equipment (hereinafter Equipment Class) as identified and set forth
below. Borrower, Structural GenomiX, Inc., herein represents and warrants that
it shall maintain each such Equipment Class and its respective Concentration
Requirement from and after such above referenced date and continuing thereafter
to the end of the funding term:

<TABLE>
<CAPTION>
EQUIPMENT CLASS                          CONCENTRATION REQUIREMENT
---------------                          -------------------------
<S>                                      <C>
Laboratory Equipment                     Minimum of 40%

Computer Equipment                       Maximum of 11%

Beam Line Equipment                      Maximum of 6%

Tenant Improvements and Software         Maximum of 43%
</TABLE>

Dated as of: August 28,2002

OXFORD FINANCE CORPORATION               STRUCTURAL GENOMIX, INC.

By:      /s/ Karl Hefty                  By:      /s/ Herbert G. Mutter
         -----------------------------            ------------------------------

Name:    Karl Hefty                      Name:    Herbert G. Mutter
         -----------------------------            ------------------------------

Title:   VP & Portfolio Manager          Title:   Vice President, Finance
         -----------------------------            ------------------------------

<PAGE>

                               EQUIPMENT SCHEDULE
                                       TO
                       MASTER LOAN AND SECURITY AGREEMENT
--------------------------------------------------------------------------------

MASTER LOAN AND SECURITY AGREEMENT NO. 2081008            DATED: August 28, 2002
EQUIPMENT SCHEDULE NO. 01

LENDER:                                  BORROWER:

OXFORD FINANCE CORPORATION               STRUCTURAL GENOMIX, INC.
133 NORTH FAIRFAX STREET                 10505 ROSELLE STREET
ALEXANDRIA, VIRGINIA 22314               SAN DIEGO, CA 92121

LENDER AND BORROWER HAVE ENTERED INTO MASTER LOAN AND SECURITY AGREEMENT NO.
2081008 DATED August 28, 2002 (THE "AGREEMENT") WHICH IS INCORPORATED HEREIN.
THIS IS AN EQUIPMENT SCHEDULE TO THE AGREEMENT. ALL WORDS AND TERMS USED HEREIN
AND NOT SPECIFICALLY DEFINED HEREIN SHALL HAVE THE SAME MEANINGS AS SET FORTH IN
THE AGREEMENT.

      1. EQUIPMENT LOCATION (if other than above address of Borrower): 10581
Roselle Street, San Diego, CA 92121 AND 3770 Tansy Street, San Diego, CA 92121
AND 9700 South Cass Avenue, Argonne, IL 60439.

      2. EQUIPMENT: (See attached Exhibit A)

      3. ACQUISITION COST OF THE EQUIPMENT: $1,448,029.34.

      4. SUPPLIER(S): See Attached.

      5. THE LOAN AND LOAN AGREEMENT REPAYMENT. As requested by Borrower
pursuant to the Agreement, Lender agrees to lend to Borrower the sum of
$1,448,029.34. Borrower agrees to repay the Loan Agreement in successive
installments (which installment payments are inclusive of interest) as set forth
in the following Schedule:

      SCHEDULE

      Advance Payment Amount: $73.632.30 (first and last payments up front)

      Number of Installments (Exclusive of Advance Payment):  46

      Payment Period:   [X] Monthly   [ ] Quarterly

      Periodic Installment Payment mount Per Period:  $36,816.15

      Commencement Date:  September 3, 2002

      Special provisions (if any):  Warrant

      6. SECURITY DEPOSIT: none.

      7. DISBURSEMENT OF PROCEEDS. Borrower hereby authorizes Lender to disburse
the $1,448,029.34 proceeds as follows:

            (a)   $1,448,029.34       to:      Structural GenomiX, Inc.

                  $1,448,029.34                TOTAL PROCEEDS

                                  Page 1 of 2
<PAGE>
                               EQUIPMENT SCHEDULE
                                       TO
                       MASTER LOAN AND SECURITY AGREEMENT
--------------------------------------------------------------------------------

Borrower may direct the Lender in writing to withhold payments from Supplier(s),
either now or in the future. Lender shall be entitled to rely on such written
direction of Borrower as being conclusive as to the intent of the Borrower with
regard to withheld payments.

Borrower hereby acknowledges and agrees that it shall constitute an additional
Event of Default under the Loan Agreement if, for any reason, the Acquisition
Cost of the Equipment has not been fully paid to the appropriate Supplier(s)
thereof within ten (10) days after demand therefor by Lender. Borrower hereby
agrees to indemnify, and hold harmless Lender from and against any liability,
claim, loss or damage, including reasonable Attorneys' Fees and Expenses, that
may be incurred by Lender as a result of any amounts to be withheld hereunder,
including any claims of the Supplier(s) therefor.

      8. ADJUSTMENTS: Borrower acknowledges that payments under the Loan
Agreement herein are based upon the Acquisition Cost of the Equipment set forth
above, and as a result of authorized changes to the Equipment, the final
Acquisition Cost of the Equipment may increase or decrease by up to 10%. In such
event, the Loan Payments shall be adjusted accordingly, and Borrower authorizes
Lender to correct the Loan Agreement (and all related documentation) to reflect
such changes and Borrower, if requested by Lender, shall confirm such changes to
Lender in writing.

      9. SEE RATE ADJUSTMENT RIDER ATTACHED AND INCORPORATED BY REFERENCE.

By execution hereof, the signer certifies that he/she is a duly authorized
officer, partner or proprietor of Borrower and that he/she has read, accepted
and duly executed this Equipment Schedule to the Master Loan and Security
Agreement on behalf of Borrower.

ACCEPTED AT LENDER'S OFFICE AT ALEXANDRIA, VIRGINIA.

OXFORD FINANCE CORPORATION               STRUCTURAL GENOMIX, INC.
(LENDER)                                 (BORROWER)

By:    /s/ Karl Hefty                    By:    /s/ Herbert G. Mutter
       -------------------------------          --------------------------------

Name:  Karl Hefty                        Name:  Herbert G. Mutter
       -------------------------------          --------------------------------

Title: VP & Portfolio Manager            Title: Vice President, Finance
       -------------------------------          --------------------------------

Date:  9/03/02                           Date:  8/28/02
       -------------------------------          --------------------------------

                                  Page 2 of 2
<PAGE>

                                    EXHIBIT A
                                       TO
                               EQUIPMENT SCHEDULE
--------------------------------------------------------------------------------

                               LIST OF EQUIPMENT

The following list and description of Equipment supplements and forms a part of
Equipment Schedule No. 01 to Master Loan and Security Agreement No. 2081008
dated August 28, 2002 between Lender and Borrower and may be attached to said
Equipment Schedule and any related UCC Financing Statements, or other document
relating to the Master Loan and Security Agreement, the Equipment Schedule or
any other document describing the Equipment.

                SEE ATTACHED EQUIPMENT SCHEDULE DETAIL EXHIBIT A

All property listed above, together with any and all attachments, accessions,
additions, replacements, improvements, modifications and substitutions thereto
and therefor and a right to use license for any software related to any of the
foregoing now or hereafter acquired and all proceeds, in the form of goods,
accounts, chattel paper, documents, instruments and insurance proceeds.

OXFORD FINANCE CORPORATION               STRUCTURAL GENOMIX, INC.
(LENDER)                                 (BORROWER)

By:    /s/ Karl Hefty                    By:    /s/ Herbert G. Mutter
       -------------------------------          --------------------------------

Name:  Karl Hefty                        Name:  Herbert G. Mutter
       -------------------------------          --------------------------------

Title: VP & Portfolio Manager            Title: Vice President, Finance
       -------------------------------          --------------------------------

Date:  9/03/02                           Date:  8/28/02
       -------------------------------          --------------------------------

<PAGE>
                             FORM OF PROMISSORY NOTE
________________________________________________________________________________

TO:   MASTER LOAN AND SECURITY AGREEMENT NO. 2081008

                              Dated August 28, 2002

                            EQUIPMENT SCHEDULE NO.___

U.S. $__________________                                    Alexandria, Virginia

Dated:    _________________________

            FOR VALUE RECEIVED, STRUCTURAL GENOMIX, INC. a DELAWARE corporation
(the "Borrower"), hereby promises to pay to the order of OXFORD FINANCE
CORPORATION, or its successors or assigns (the "Payee") at its offices located
at 133 North Fairfax Street, Alexandria, Virginia 22314, or at such other place
as the Payee or any holder hereof may from time to time designate, the principal
amount of U.S. _________________________________________________________________
____________ DOLLARS ($_______), with interest (based on a year of 360 days and
30 day months) on the principal amount hereof remaining from time to time
unpaid, such principal and interest to be paid in consecutive monthly
installments until fully paid, in the manner and at a rate of interest per annum
as determined and provided in the Loan Agreement. Anything in this Note to the
contrary notwithstanding, in the event that any payment of interest hereunder
shall exceed the legal limit, such amount in excess of such limit shall be
deemed a payment of principal hereunder.

This Note evidences a loan by the Payee to the undersigned, pursuant to the Loan
Agreement indicated above between the undersigned and the Payee as from time to
time may be amended, restated, replaced, supplemented, substituted for or
renewed, and the holder of this Note is entitled to the benefits thereof,
including without limitation, the security interest in the Equipment granted
therein. Each term defined in the Loan Agreement and not otherwise defined
herein shall have the same definition when used herein.

The principal hereof and accrued interest hereon shall become forthwith due and
payable as provided in the Loan Agreement. Payments hereunder not made when due
shall accrue late charges as provided in the Loan Agreement. This Note may not
be prepaid in whole or in part except as otherwise specifically provided in the
Loan Agreement.

The Borrower hereby waives diligence, demand, presentment, protest and notice of
any kind, and assents to extensions of the time of payment, release, surrender
or substitution of security, or forbearance or other indulgence, without notice.
No act or omission of the Payee, including without limitation any failure to
exercise any right, remedy or recourse, shall be deemed to be a waiver or
release of such right, remedy or recourse. Any waiver or release may be effected
only by a written document executed by Payee and then only to the extent
specified therein. The undersigned hereby promises to pay all reasonable
Attorneys Fees and Expenses that may be incurred in connection with the
enforcement and/or collection of this Note.

The undersigned authorizes the Payee to insert above as the date of the Note,
the date on which Payee disburses funds pursuant to the Loan Agreement.

This Note is freely assignable by the Payee, in whole or in part, and from time
to time. All of the terms and provisions of this Note inure to and are binding
upon the heirs, executors, administrators, successors, representatives,
receivers, trustees and assigns of the parties. None of the rights or
obligations of the Borrower hereunder may be assigned or otherwise transferred
without the prior written consent of the Payee.

THIS NOTE AND THE LEGAL RELATIONS OF THE PARTIES HERETO SHALL IN ALL RESPECTS BE
GOVERNED BY AND CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE COMMONWEALTH OF
VIRGINIA, WITHOUT REGARD TO PRINCIPLES REGARDING THE CHOICE OF LAW. BORROWER
HEREBY CONSENTS AND SUBMITS TO THE NON-EXCLUSIVE JURISDICTION OF THE COURTS OF
THE COMMONWEALTH OF VIRGINIA AND THE FEDERAL DISTRICT COURT FOR THE

________________________________________________________________________________

                                   Page 1 of 2
<PAGE>
                             FORM OF PROMISSORY NOTE
________________________________________________________________________________

COMMONWEALTH OF VIRGINIA FOR THE PURPOSES OF ANY SUIT, ACTION OR OTHER
PROCEEDING ARISING OUT OF ITS OBLIGATIONS HEREUNDER, AND EXPRESSLY WAIVES ANY
OBJECTIONS THAT IT MAY HAVE TO THE VENUE OF SUCH COURTS. BORROWER HEREBY
EXPRESSLY WAIVES ANY RIGHT TO TRIAL BY JURY IN ANY ACTION BROUGHT ON OR WITH
RESPECT TO THIS NOTE.

            IN WITNESS WHEREOF, the Borrower by its duly authorized officer has
executed and delivered this Note as of the date first above written.

                                                  STRUCTURAL GENOMIX, INC.

                                     By:    ____________________________________

                                     Name:  ____________________________________

                                     Title: ____________________________________

________________________________________________________________________________

                                   Page 2 of 2
<PAGE>
                          SCHEDULE OF PROMISSORY NOTES

<TABLE>
<CAPTION>
           NUMBER                DATE                   PRINCIPAL AMOUNT
           ------                ----                   ----------------
<S>                           <C>                       <C>
              1                 9/3/2002                 $1,448,029.34
              2                 9/3/2002                 $1,803,395.89
              3               12/27/2002                   $700,515.67
              4                4/30/2003                   $347,347.10
              5                4/30/2003                   $235,678.50
              6                7/30/2003                   $270,590.10
              7                7/30/2003                    $89,645.08
              8               12/19/2003                   $180,631.41
              9               12/19/2003                   $178,554.85
             10                5/28/2004                   $420,400.68
             11                5/28/2004                   $221,667.20
</TABLE>

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00090-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00090-of-00352.parquet"}]]