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                                                                  EXHIBIT 10.53


                   INDEPENDENT CONTRACTOR SERVICES AGREEMENT

     This Independent Contractor Services Agreement ("CONTRACTOR AGREEMENT") is
made and entered into by and between Invitrogen Corporation ("COMPANY"), a
Delaware corporation, having a principal place of business at 1600 Faraday
Avenue, Carlsbad, California 92008, and Lyle C. Turner, an individual
("CONTRACTOR") whose address is PO Box 906, Rancho Santa Fe, CA, 92067. In
consideration of the promises and mutual agreements hereinafter set forth, and
expressly contingent on Contractor fully executing and not revoking the
Confidential Separation Agreement and General Release of All Claims ("SEPARATION
AGREEMENT") of even date herewith, it is agreed by and between the undersigned
as follows:

     1.   Engagement of Services. Company hereby agrees to retain Contractor as
a consultant, in an independent contractor relationship, effective January 1,
2003 ("EFFECTIVE DATE"), pursuant to the terms of this Contractor Agreement.
Contractor's consulting services will include, but not be limited to, advising
management and Company's Board of Directors on matters relating to strategic
direction and merger and acquisition strategy. Company will consult with
Contractor on an as-needed basis, at the discretion of the Company. Contractor
agrees to make himself available for consulting services for up to ten (10)
hours per month.

     2.   Compensation.

          2.1  Fees for Services. Company shall pay Contractor a total fee for
services rendered of One Million Four Hundred Thirty Thousand Dollars
($1,430,000) (the "FEE"). The Fee will be paid in four (4) equal quarterly
installments by wire transfer to Contractor's account pursuant to wiring
instructions that shall be provided to Company in writing by Contractor. Such
payments will be made on the dates set forth below.

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          INSTALLMENT                        PAYMENT DATE
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          1st Installment                    March 31, 2003
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          2nd Installment                    June 30, 2003
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          3rd Installment                    September 30, 2003
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          4th and Final Installment          December 31, 2003
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          2.2  Expenses. Company shall reimburse Contractor for reasonable
expenses incurred in connection with Contractor's performance of services under
this Contractor Agreement, provided that expenses in excess of $500 are approved
in advance by Company and Contractor promptly provides documentation
satisfactory to Invitrogen to support Contractor's request for reimbursement and
provided further that Contractor may require Company to advance approved
expenses in excess of $500. Reimbursements for such expenses shall be made
within thirty (30) days of receiving supporting documentation from Contractor.

     3.   Independent Contractor Relationship. Contractor's relationship with
Company will be that of an independent contractor, and nothing in this
Contractor Agreement is intended to, or should be construed to, create a
partnership, agency, joint venture or employment


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relationship. Contractor will not be entitled under this Contractor Agreement to
any of the benefits that Company may make available to its employees,
including, but not limited to, group health, life insurance, profit-sharing or
retirement benefits, paid vacation, holidays or sick leave, or workers'
compensation insurance. Contractor will not be authorized to make any
representation, contract or commitment on behalf of Company unless specifically
requested or authorized in writing to do so by Company's Board of Directors.
Contractor will be solely responsible for obtaining any business or similar
licenses required by any federal, state or local authority. In addition,
Contractor will be solely responsible for, and will file on a timely basis, all
tax returns and payments required to be filed with, or made to, any federal,
state or local tax authority with respect to the performance of services and
receipt of fees under this Contractor Agreement. No part of Contractor's
compensation will be subject to withholding by Company for the payment of any
social security, federal, state or any other employee payroll taxes. Company
will regularly report amounts paid to Contractor by filing a Form 1099-MISC
with the Internal Revenue Service as required by law.

          3.1  Method of Performing Services; Results. In accordance with
Company objectives, Contractor will determine the method, details and means of
performing the services required by this Contractor Agreement. Company shall
have no right to, and shall not, control the manner or determine the method of
performing Contractor's services. Contractor shall provide the services for
which Contractor is engaged to the reasonable satisfaction of Company.

          3.2  Workplace, Hours and Instrumentalities. Contractor may perform
the services required by this Contractor Agreement at any place or location and
at such times as Contractor shall determine. Contractor agrees to provide all
tools and instrumentalities, if any, required to perform the services under
this Contractor Agreement.

     4.   Protection of Proprietary Rights.

          4.1  Definition of Confidential Information. "CONFIDENTIAL
INFORMATION" as used in this Contractor Agreement shall mean any and all
technical and non-technical information including patent, copyright, trade
secret, and proprietary information, techniques, sketches, drawings, models,
inventions, know-how, processes, apparatus, equipment, algorithms, software
programs, software source documents, computer files and models, and formulae
related to the past, current, future and proposed products and services of
Company, Company's suppliers and customers, and includes, without limitation,
Company innovations, Company property, and Company's information concerning
research, experimental work, development, design details and specifications,
engineering, financial information, procurement requirements, purchasing
manufacturing, customer lists, business forecasts, sales and merchandising and
marketing plans and information.

          4.2  Nondisclosure and Nonuse Obligations. Contractor agrees to
protect the confidentiality of all Confidential Information and, except as
permitted in this section, Contractor shall neither use nor disclose the
Confidential Information. Contractor may use the Confidential Information
solely to perform services as a consultant under this Contractor Agreement for
the benefit of the Company. Contractor will immediately give notice to Company
of any unauthorized use or unauthorized disclosure of the Confidential
Information. Contractor agrees to assist Company in remedying any such
unauthorized use or unauthorized disclosure of the Confidential Information.
Contractor also agrees not to communicate any information to Company in
violation of the proprietary rights of any third party.


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          4.3  Exclusion from Nondisclosure and Nonuse Obligations. Contractor's
obligations under Section 4.2 ("NONDISCLOSURE AND NONUSE OBLIGATIONS") with
respect to any portion of the Confidential Information shall not apply to any
such portion which Contractor can demonstrate, (a) was in the public domain at
or subsequent to the time such portion was communicated to Contractor by Company
through no fault of Contractor; (b) was rightfully in Contractor's possession
free of any obligation of confidence at or subsequent to the time such portion
was communicated to Contractor by Company; or (c) was developed by Contractor
independently of and without reference to any information communicated to
Contractor by Company. A disclosure of Confidential Information by Contractor,
either (i) in response to a valid order by a court or other governmental body,
(ii) otherwise required by law, or (iii) necessary to establish the rights of
either party under this Contractor Agreement, shall not be considered to be a
breach of this Contractor Agreement or a waiver of confidentiality for other
purposes; provided, however, that Contractor shall provide prompt prior written
notice thereof to Company to enable Company to seek a protective order or
otherwise prevent such disclosure.

          4.4  Ownership and Return of Company Property. All materials
(including, without limitation, documents, drawings, models, apparatus,
sketches, designs, lists, and all other tangible media of expression) furnished
to Contractor by Company, whether delivered to Contractor by Company or made by
Contractor in the performance of services under this Contractor Agreement, and
all other property of Company (including, without limitation, all Confidential
Information, computers, computer software and computer disks), (collectively,
the "COMPANY PROPERTY") are the sole and exclusive property of Company or
Company's suppliers or customers, and Contractor hereby does and will assign to
Company all rights, title and interest Contractor may have or acquire in the
Company Property. Contractor also acknowledges and agrees that all work product
developed by him alone or in conjunction with others in connection with the
performance of services pursuant to this Contractor Agreement is and shall be
the sole property of Company, and Contractor shall retain no ownership, interest
or rights therein. Upon termination of this Contractor Agreement, for any
reason, or no later than five (5) days after Company's request, Contractor will
immediately destroy or deliver to Company, at Company's option, (a) all Company
Property, including all copies and excerpts of same, (b) all tangible media of
expression in Contractor's possession or control which incorporate or in which
are fixed any Confidential Information, and (c) written certification of
Contractor's compliance with Contractor's obligations under this sentence.

          4.5  Continuing Obligations Under Confidentiality Agreements.
Contractor acknowledges that the Trade Secrets New Employee Orientation
Agreement dated August 12, 1997 and the Employee's Agreement Relating to Company
Information and Technology dated May 14, 1997, he signed during his employment
with Company and the Company's Insider Trading Policy executed by Contractor
contemporaneously with this Contractor Agreement (collectively referred to as
the "CONFIDENTIALITY AGREEMENTS") will remain in effect during the term of this
Contractor Agreement, and Contractor agrees to continue to comply with the
Confidentiality Agreements during the term of this Contractor Agreement.
Contractor also recognizes that certain provisions of the Confidentiality
Agreements survive the termination of this Contractor Agreement, and Contractor
agrees to comply with all such surviving provisions. The parties agree that the
provisions of Item 6.2 and 8 of The Employee's Agreement Relating to Company
Information and Technology dated May 14, 1997 that Contractor signed in
connection with his employment as continued during the term of this Contractor
Agreement are limited in their application to matters which relate to the
business of Company, which are based on or derived from Company Information,
which result from work performed for Company, or which are made with the use of
Company equipment, supplies or facilities.


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     5.   No Conflict of Interest. During the term of this Contractor Agreement,
Contractor will not accept work, enter into a contract, provide financial
support, or accept an obligation, inconsistent or incompatible with his
obligations, or the scope of services rendered for Company under this Contractor
Agreement, including, but not limited to, directly or indirectly competing with
Company in any way, including, without limitation, engaging in competitive
research and development activities, or acting as an officer, director, partner,
manager, employee, consultant, stockholder, volunteer, lender, principal or
agent of any business enterprise of the same nature as, or which is in direct
competition with, any business in which Company is now engaged or in which
Company becomes engaged during the term of this Contractor Agreement. Contractor
warrants that, to the best of his knowledge, there is no other contract or duty
on his part that conflicts with or is inconsistent with this Contractor
Agreement. Notwithstanding the above, Contractor is permitted to own up to 1% of
the listed or traded stock of any publicly held corporation. For purposes of
this section 5, the term "Company" shall mean and include Company, any
subsidiary or affiliate of Company and any successor to the business of Company
(by merger, consolidation, sale of assets or stock or otherwise).

     6.   Term and Termination.

          6.1  Automatic Termination Upon Expiration of Term. The term of this
Contractor Agreement will commence on January 1, 2003 and terminate
automatically on December 31, 2003.

          6.2  Early Termination by Company. Company may terminate this
Contractor Agreement (a) immediately upon Contractor's material breach of
section 4 ("PROTECTION OF PROPRIETARY RIGHTS"), section 5 ("CONFLICT OF
INTEREST") or the Separation Agreement; or (b) thirty (30) days after Company's
delivery to Contractor of written notice of Contractor's material breach of any
other provision or obligation owed by Contractor under this Contractor Agreement
which is not cured by him within such thirty (30) day period.

          6.3  Early Termination by Contractor. Contractor may terminate this
Contractor Agreement for a material breach by Company if Company has not cured
the breach within thirty (30) days of receiving written notice from Contractor;
provided, however, that no such notice or cure provision shall apply with
respect to the payment of the Fee described in section 2.1 above.

          6.4  Payment of Fees Cease Upon Termination. Upon termination of this
Contractor Agreement pursuant to section 6.2, Company shall immediately cease
payment of the Fee described in section 2 above. Upon termination of this
Contractor Agreement pursuant to section 6.3, any portion of the Fee not yet
paid to Contractor shall become due and payable upon demand by Contractor. Any
amount not timely paid to Contractor shall bear interest at the rate of two
percent (2%) per month, compounded daily.

     7.   Nonsolicitation. Contractor understands and agrees that Company
believes its employees and customers and any information regarding Company's
employees and/or customers is confidential and constitutes trade secrets.
Accordingly, Contractor agrees that during the term of this Contractor Agreement
and for a period of one (1) year after the termination of this Contractor
Agreement, Contractor will not, either directly or indirectly, separately or in
association with others: (a) take action likely to interfere with, impair,
disrupt or damage Company's relationship with any of its customers, customer
prospects, vendors, contractors, collaborators, joint venturers, partners,
licensors, or licensees by soliciting or encouraging others to solicit any of
them for the purpose of diverting or taking away business or

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opportunities from Company; or (b) interfere with, impair, disrupt or damage
Company's business by soliciting or attempting to hire any of Company's
employees or causing others to solicit or encourage any of Company's employees
to discontinue their employment with Company; provided, however, that
Contractor being named as a referral on the resume of a Company employee and
Contractor responding to inquiries resulting therefrom shall not violate this
Agreement.

     8.   General Provisions.

          8.1  Successors and Assigns.  Contractor may not subcontract or
otherwise delegate Contractor's obligations under this Contractor Agreement
without Company's prior written consent. Subject to the foregoing, this
Contractor Agreement will be for the benefit of Company's successors and
assigns, and will be binding on Contractor's assignees.

          8.2  Notices.  Any notice required or permitted by this Contractor
Agreement shall be in writing and shall be delivered as follows, with notice
deemed given as indicated: (a) by personal delivery, when delivered personally;
(b) by overnight courier, upon written verification of receipt; (c) by telecopy
or facsimile transmission, upon acknowledgment of receipt of electronic
transmission; or (d) by certified or registered mail, return receipt requested,
upon verification of receipt. Notice shall be sent to the addresses set forth
above or to such other address as either party may specify in writing.

          8.3  Governing Law.  This Contractor Agreement shall be governed in
all respects by the laws of the United States of America and by the laws of the
State of California, as such laws are applied to agreements entered into and to
be performed entirely within California between California residents. Each of
the parties irrevocably consents to the exclusive personal jurisdiction of the
federal and state courts located in California, as applicable, for any matter
arising out of or relating to this Contractor Agreement, except that in actions
seeking to enforce any order or any judgment of such federal or state courts
located in California, such personal jurisdiction shall be nonexclusive.

          8.4  Severability. If any provision of this Contractor Agreement is
held by a court of law to be illegal, invalid or unenforceable, (a) that
provision shall be deemed amended to achieve as nearly as possible the same
economic effect as the original provision, and (b) the legality, validity and
enforceability of the remaining provisions of this Contractor Agreement shall
not be affected or impaired thereby.

          8.5  Waiver; Modification. No term or provision hereof will be
considered waived by either party, and no breach excused, unless such waiver or
consent is in writing and signed by Company's Chairman of the Board of
Directors and Contractor. The waiver of, or consent to, a breach of any
provision of this Contractor Agreement shall not operate or be construed as a
waiver of, consent to, or excuse of any other or subsequent breach by either
party. This Contractor Agreement may be amended or modified only in writing by
mutual agreement of authorized representatives of the parties.

          8.6  Injunctive Relief for Breach. Contractor agrees that his
obligations under this Contractor Agreement are of a unique character that
gives them particular value; Contractor's breach of any of such obligations
will result in irreparable and continuing damage to Company for which there
will be no adequate remedy at law; and, in the event of such breach, Company
will be entitled to injunctive relief and/or a decree for specific performance,
and such other and further relief as may be proper (including monetary damages
if appropriate).

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     8.7  Survival. The definitions contained herein and the rights and
obligations contained in sections 4 ("Protection of Proprietary Rights"), 7
("Nonsolicitation"), and 8 ("General Provisions") will survive any termination
or expiration of this Contractor Agreement.

     8.8  Counterparts. This Contractor Agreement may be executed in
counterparts. The execution of a signature page of this Contractor Agreement
shall constitute the execution of the Contractor Agreement, and the Contractor
Agreement shall be binding on each party upon the date of signature, if each
party executes such counterpart.

     8.9  Entire Agreement. This Contractor Agreement constitutes the entire
agreement between the parties relating to the provision of consulting services
by Contractor to Company and supersedes all prior or contemporaneous oral or
written agreements concerning this subject matter. The terms of this Contractor
Agreement will govern all consulting services undertaken by Contractor for
Company.

IN WITNESS WHEREOF, the parties have executed this Contractor Agreement on
12/13, 2002.

INVITROGEN CORPORATION                       CONTRACTOR

By: /s/ John A. Cottingham                   By: /s/ Lyle C. Turner
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   John A. Cottingham                           Lyle C. Turner
   Vice President, General Counsel
     and Secretary


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