EXHIBIT 10.9



THIRD AMENDED AND RESTATED
LINE OF CREDIT NOTE


$3,000,000                                                      FEBRUARY 7, 2000


     FOR  VALUE  RECEIVED,   INFORMAX,   INC.,  a  Delaware   corporation   (the
"BORROWER"), promises to pay to the order of PNC BANK, NATIONAL ASSOCIATION (the
"BANK"),  in  lawful  money of the  United  States  of  America  in  immediately
available  funds,  the  principal  sum of the  lesser of THREE  MILLION  DOLLARS
($3,000,000)  (the "EQUIPMENT  LINE") or the aggregate  advances made hereunder,
together with interest  accruing on the outstanding  principal  balance from the
date hereof, as provided below:

     1.  LOAN  AGREEMENT.  This  Note is  issued  in  connection  with  the Loan
Agreement  dated as of May 6, 1999 by and between the Borrower and the Bank,  as
amended by Amendment No. 1 to Loan Agreement dated August 6, 1999, Amendment No.
2 to Loan  Agreement  dated  November  30,  1999  and  Amendment  No.  3 to Loan
Agreement dated the date hereof (as amended, the "LOAN AGREEMENT"), the terms of
which are incorporated herein by reference, and evidences the obligations of the
Borrower to the Bank with respect to Advances  under the Equipment Line (as each
such term is defined in the Loan Agreement, each such Advance referred to herein
as an "EQUIPMENT  ADVANCE").  This Note is secured by the property  described in
the Loan Agreement and other loan documents  entered into in connection with the
Loan Agreement (the "LOAN DOCUMENTS") and by such other collateral as previously
may have been or may in the future be  granted  to the Bank to secure  this Note
and the  obligations  of the  Borrower  under the  November  1999 Note  (defined
below).

     2. RATE OF INTEREST. Amounts outstanding under this Note will bear interest
at a rate per annum  determined in accordance with the Loan Agreement.  Interest
will be  calculated  on the basis of a year of 360 days for the actual number of
days in each interest period.

     3.  ADVANCES.  The Borrower may borrow  hereunder  until the Equipment Line
Expiration  Date,  subject to the terms and conditions of this Note and the Loan
Documents (as defined  herein).  The "EQUIPMENT LINE EXPIRATION DATE" shall mean
February 2, 2001. In no event shall the  aggregate  unpaid  principal  amount of
advances under this Note exceed the face amount of this Note.

     4.  NOTATION  OF  ADVANCES.  The Bank will enter on its books and  records,
which entry when made will, absent manifest error, be presumed correct, the date
and  amount of each  Equipment  Advance,  as well as the date and amount of each
payment made by the Borrower provided,  however, that the failure of the Bank to
make such notation  shall not limit or otherwise  affect the  obligations of the
Borrower under this Note.

     5. PAYMENT TERMS.  Interest on the aggregate  outstanding principal balance
of each  Equipment  Advance  shall  accrue  beginning  on the date of each  such
Equipment Advance.


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The  obligations of the Borrower with respect to all Equipment  Advances made by
the Bank prior to  November 6, 1999 (the  "FIRST  TERM LOAN  CONVERSION  DATE"),
together with all interest  accrued  thereon,  shall be converted to a term loan
(the "FIRST TERM LOAN") on the First Term Loan  Conversion  Date.  The  Borrower
shall make 30 equal monthly  payments of principal and interest  under the First
Term Loan beginning with November 15, 1999 through and including April 15, 2002.
The  obligations of the Borrower with respect to all Equipment  Advances made by
the Bank after the First Term Loan Conversion  Date,  together with all interest
accrued  thereon,  shall be  converted  to a second term loan (the  "SECOND TERM
LOAN") on the Equipment Line Expiration Date. The Borrower shall make 30 monthly
payments of principal and interest under the Second Term Loan beginning with the
payment  due on May 15,  2000 and  continuing  on the 15th day of each  calendar
month thereafter  through and including  October 15, 2002 (the "MATURITY DATE").
The outstanding  principal balance hereunder and any accrued but unpaid interest
shall be due and payable on the Maturity  Date.  If any payment  under this Note
shall become due on a Saturday,  Sunday or public  holiday under the laws of the
State where the Bank's principal  office is located,  such payment shall be made
on the next succeeding business day and such extension of time shall be included
in computing  interest in  connection  with such  payment.  The Borrower  hereby
authorizes the Bank to charge the Borrower's deposit account at the Bank for any
payment when due hereunder.  Payments received will be applied to charges,  fees
and  expenses  (including  reasonable  attorney's  fees),  accrued  interest and
principal in any order the Bank may choose, in its sole discretion.

     6. DEFAULT. The occurrence of any one or more of the following events shall
constitute a "DEFAULT":

     (a) the  Borrower  shall  fail to pay all or any  portion  of  interest  or
principal on this Note when due; or

     (b) an Event of Default shall occur under the Loan  Agreement or other Loan
Documents.

Upon occurrence of a Default, the entire outstanding principal balance, together
with all interest, costs, charges and other amounts outstanding under this Note,
shall  become  immediately  due and payable  and,  upon such  acceleration,  all
amounts due hereunder shall bear interest at the Default Rate (defined below).

     7. LATE  PAYMENTS;  DEFAULT RATE. If the Borrower fails to make any payment
of  principal  when due or any payment of interest  or other  amount  coming due
pursuant to the  provisions  of this Note within five (5)  business  days of the
date due and  payable,  the  Borrower  also shall pay to the Bank a late  charge
equal to the lesser of five  percent (5%) of the amount of such payment or $500.
Such five (5)  business  day period  shall not be construed in any way to extend
the due date of any such payment.  The late charge is imposed for the purpose of
defraying the Bank's  expenses  incident to the handling of delinquent  payments
and is in  addition  to,  and not in lieu of,  the  exercise  by the Bank of any
rights  and  remedies  hereunder,  under  the  other  Loan  Documents  or  under
applicable  law, and any reasonable fees and expenses of any agents or attorneys
which the Bank may employ.  At the option of the Bank upon the occurrence of any
Event of Default (as defined in the Loan  Agreement) and during the  continuance
thereof,


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this Note shall bear  interest at a rate per annum  (based on a year of 360 days
and actual days elapsed) which shall be two percentage  points (2%) in excess of
the interest  rate in effect from time to time under this Note but not more than
the maximum rate  allowed by law (the  "DEFAULT  RATE").  The Default Rate shall
continue to apply  whether or not  judgment  shall be entered on this Note until
all such Events of Default have been cured.

     8. PREPAYMENT.  The  indebtedness  evidenced by this Note may be prepaid in
whole or in part at any time  without  penalty,  but such  prepayment  shall not
entitle the Borrower to re-borrow the principal amount prepaid.

     9. NO  NOVATION.  This Third  Amended and  Restated  Line of Credit Note is
issued in  replacement  for the Second  Amended and Restated Line of Credit Note
dated  November  30,  1999  made by the  Borrower,  under  the terms of the Loan
Agreement (the "NOVEMBER 1999 NOTE"). The indebtedness evidenced by the November
1999 Note is  continuing  indebtedness  and  nothing  herein  shall be deemed to
constitute  a payment,  settlement  or novation of the  November  1999 Note,  or
release  or  otherwise  adversely  affect  any  rights of the Bank  against  the
Borrower  and all  amounts  outstanding  under the  November  1999 Note shall be
transferred  to, and be deemed to be outstanding  under,  this Third Amended and
Restated Line of Credit Note.

     10.  MISCELLANEOUS.  No delay or omission of the Bank to exercise any right
or power arising hereunder shall impair any such right or power or be considered
to be a waiver of any such  right or  power,  nor  shall  the  Bank's  action or
inaction  impair any such right or power.  The Borrower agrees to pay on demand,
to the extent  permitted by law, all costs and expenses  incurred by the Bank in
the  enforcement  of its  rights  in this  Note  and in any  security  therefor,
including without limitation reasonable fees and expenses of the Bank's counsel.
If any  provision of this Note is found to be invalid by a court,  all the other
provisions  of this Note will remain in full force and effect.  The Borrower and
all other makers and indorsers of this Note hereby  forever  waive  presentment,
protest, notice of dishonor and notice of non-payment.  The Borrower also waives
all defenses  based on suretyship or impairment of  collateral,  except for such
impairment which results from the gross negligence or willful  misconduct of the
Bank.   This  Note  shall   bind  the   Borrower   and  its  heirs,   executors,
administrators,  successors and assigns,  and the benefits hereof shall inure to
the benefit of the Bank and its successors and assigns.

     11.  GOVERNING  LAW.  THIS NOTE has been  delivered to the Bank and will be
deemed  to be  made in the  Commonwealth  of  Pennsylvania.  THIS  NOTE  WILL BE
INTERPRETED  AND THE  RIGHTS  AND  LIABILITIES  OF THE  BORROWER  AND  THE  BANK
DETERMINED  IN ACCORDANCE  WITH THE LAWS OF THE  COMMONWEALTH  OF  PENNSYLVANIA,
EXCLUDING ITS CONFLICT OF LAWS RULES. The Borrower hereby  irrevocably  consents
to the exclusive  jurisdiction of any state or federal court seated in Allegheny
County,  Pennsylvania,  and  consents  that all  service  of  process be sent by
nationally  recognized overnight courier service directed to the Borrower at the
Borrower's  address set forth in the Loan  Agreement and service so made will be
deemed to be  completed on the  business  day after  deposit with such  courier;
provided that nothing contained in this Note will prevent the


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Bank from bringing any action, enforcing any award or judgment or exercising any
rights  against the Borrower  individually,  against any security or against any
property of the  Borrower  within any other  county,  state or other  foreign or
domestic jurisdiction.  The Borrower agrees that the venue provided above is the
most  convenient  forum for both the Bank and the Borrower.  The Borrower waives
any objection to venue and any objection based on a more convenient forum in any
action instituted under this Note.

     12.  WAIVER OF JURY  TRIAL.  THE  BORROWER  IRREVOCABLY  WAIVES ANY AND ALL
RIGHTS THE  BORROWER  MAY HAVE TO A TRIAL BY JURY IN ANY ACTION,  PROCEEDING  OR
CLAIM OF ANY NATURE RELATING TO THIS NOTE, ANY DOCUMENTS  EXECUTED IN CONNECTION
WITH THIS NOTE OR ANY TRANSACTION  CONTEMPLATED  IN ANY OF SUCH  DOCUMENTS.  THE
BORROWER ACKNOWLEDGES THAT THE FOREGOING WAIVER IS KNOWING AND VOLUNTARY.

     The  Borrower  acknowledges  that it has  read  and  understood  all of the
provisions of this Note, including waiver of jury trial, and has been advised by
counsel as necessary or appropriate.


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     WITNESS the due execution of this Third Amended and Restated Line of Credit
Note as a document  under seal,  as of the date first  written  above,  with the
intent to be legally bound hereby.


                                      INFORMAX, INC.

                                      By: /s/ Alexander Titomirov
                                          -------------------------------
                                      Title: President/CEO
                                            ----------------------------




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