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                                                                     EXHIBIT 8.2



                                February 6, 2001



PanVera Corporation
545 Science Drive
Madison, Wisconsin 53711

        Re:    Federal Income Tax Consequences of Merger between PanVera
               Corporation and Aurora Acquisition Corp.

Ladies and Gentlemen:

        We have acted as counsel for PanVera Corporation ("PanVera") in
connection with the negotiation and execution of the Agreement and Plan of
Merger and Reorganization by and among Aurora Biosciences Corporation
("Aurora"), Aurora Acquisition Corporation ("Aurora Sub") and PanVera dated as
of November 16, 2000 (the "Agreement") pursuant to which Aurora Sub will be
merged with and into PanVera (the "Merger"). This letter furnishes you with our
opinion, as required pursuant to Section 7.3(e) of the Agreement, as to certain
of the federal income tax consequences of the Merger.

        For purposes of the opinions set forth below, we have relied, with the
consent of Pan Vera and the consent of Aurora and Aurora Sub, upon the accuracy
and completeness of the statements and representations (which statements and
representations we have neither investigated nor verified) contained,
respectively, in the letter from PanVera dated the date hereof, and the letter
from Aurora and Aurora Sub dated the date hereof (a copy of each of which is
attached hereto and incorporated herein by reference) and have assumed that the
statements in such letters will be true, complete and accurate as of the
effective time. Such letters are referred to herein collectively as the "Tax
Letters".

        The following is a description of the relevant terms of the transaction
based on our examination of the Agreement and our understanding of the related
factual background.

Parties

        PanVera is a corporation headquartered in Madison, Wisconsin. PanVera
develops products and technologies that allow pharmaceutical companies to select
and develop new drugs more rapidly and cost-efficiently. PanVera has produced
hundreds of recombinant proteins for commercial sale, focusing on protein
families that are of broad interest from a therapeutic perspective, including
nuclear receptors, protein kinases and drug metabolizing enzymes. PanVera has
one class of common stock outstanding. PanVera is not publicly traded.

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PanVera Corporation
February 6, 2001
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        Aurora designs, develops and commercializes propriety drug discovery
systems and technologies to accelerate and enhance discovery of new medicines by
the biopharmaceutical industries. Aurora is a leader in the innovation and
commercialization of technologies that accelerate and enhance the discovery of
new medicines. Aurora is currently developing a propriety biology and high
technology platform comprised of a portfolio of propriety functional genomics
technologies. Aurora's common stock (the "Aurora Common Stock") is listed on the
NASDAQ National Market.

Proposed Transaction

        In the proposed transaction, PanVera will merge (the "Merger") with
Aurora Sub, a wholly-owned subsidiary of Aurora. As a result of the Merger,
PanVera shareholders will receive shares of Aurora Common Stock in exchange for
their PanVera shares and holders of options to purchase PanVera common stock
will receive options to purchase Aurora Common Stock in exchange for their
PanVera options.

        The number of shares of Aurora Common Stock to be issued and reserved
for issuance in the Merger is fixed at 1,900,000.

        Upon completion of the Merger, each share of PanVera common stock then
outstanding will be converted into the right to receive that number of shares of
Aurora Common Stock, called the "exchange ratio," that is equal to 1,900,000
shares of Aurora Common Stock divided by the sum of the number of shares of
PanVera common stock issued and outstanding immediately prior to the effective
time of the Merger plus the number of shares of PanVera common stock issuable
for securities convertible or exchangeable into PanVera common stock that are
issued and outstanding immediately prior to the effective time of the Merger. In
addition, when the Merger becomes effective, each option to purchase PanVera
common stock that is outstanding will be converted into an option to purchase a
number of shares of Aurora Common Stock equal to the number of shares of PanVera
stock subject to the option, multiplied by the exchange ratio. The Aurora
options to be issued in the Merger will have terms which are substantially
identical to the terms of the PanVera options they replace (for example, the
term, exercisability, vesting schedule and other provisions will remain
unchanged).

        No fractional shares will be issued. PanVera shareholders that otherwise
would receive fractional shares will instead receive cash in an amount equal to
the fractional share they otherwise would have received, multiplied by the
closing sales price of Aurora Common Stock as quoted on the NASDAQ National
Market on the last trading day prior to the closing date of the Merger.



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PanVera Corporation
February 6, 2001
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Conclusions

        Based on our examination of the Agreement, the foregoing description and
the representations made to us, including the representations made in the Tax
Letters, and assuming that the transaction is consummated in accordance with the
terms of the Agreement, and that the Merger qualifies as a statutory Merger
under the applicable laws of the State of Wisconsin, it is our opinion that for
federal income tax purposes:

               The Merger will be a reorganization within the meaning of Section
        368(a) of the Internal Revenue Code of 1986, as amended (the "Code").
        PanVera, Aurora and Aurora Sub will each be "a party to the
        reorganization" within the meaning of Code Section 368(b).

        Our opinion is not, nor should it be construed or relied upon as, a
guaranty, nor is it in any way binding on Internal Revenue Service. Our opinion
is dated as of the date hereof and we do not undertake any obligation to update
or supplement this opinion.

        We consent to the use of this opinion as an exhibit to the Registration
Statement on Form S-4 being filed by Aurora to register the shares of Aurora
Common Stock issuable in the Merger. In giving this opinion, however, we do not
admit that we are "experts" within the meaning of Section 11 of the Securities
Act of 1933, as amended (the "Act") or within the categories of persons whose
consent is required by Section 7 of the Act.


                                             Very truly yours,


                                             /s/ GODFREY & KAHN, S.C.
                                             GODFREY & KAHN, S.C.



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