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                                                                    EXHIBIT 99.1

          ENCHIRA BIOTECHNOLOGY RAISES $12.8 MILLION IN PRIVATE FINANCING

THE WOODLANDS, Texas, Sept. 12 /PRNewswire/ -- Enchira Biotechnology
Corporation ENBC, a company developing Directed Evolution technologies for
improving genes and related proteins, today announced that the company raised
$12.8 million in a private financing. The financing consisted of shares of the
Company's common stock and warrants to purchase shares of common stock. The
round was led by OrbiMed Advisors LLC and included Oracle Investment
Management and Zesiger Capital Group LLC.

Enchira plans to use the funds to accelerate the commercialization of its
proprietary Directed Evolution technology platform that is being applied to
the life sciences and industrial enzyme industries.

"This funding allows us to continue building our capabilities in the life
sciences sector, where our proprietary RACHITT-TM- technology may have
significant value," commented Peter P. Policastro, Ph.D., President and CEO of
Enchira. "We are now well positioned to leverage the inherent technological
advantages of our technology in rapidly creating hybrid genes that code for
proteins with desired characteristics."

Enchira Biotechnology is using its RACHITT-TM- gene shuffling technology
--named for "random chimeragenesis on transient templates" -- to build
extensive libraries of hybrid genes with diverse properties for its commercial
and academic partners. RACHITT-TM- generates new genes in a controlled
laboratory setting by combining genes or gene fragments to produce chimeric
genes in a combinatorial fashion. High Throughput screening systems are used
to identify particular genes that will direct the synthesis of highly
optimized proteins.

Enchira Biotechnology of The Woodlands, Texas is applying proprietary,
directed evolution techniques to accelerate development and commercialization
of biocatalyst-based processes for the pharmaceutical, industrial enzyme and
ag-bio markets. Additional information is available at the company's web site:
http://www.enchira.com.

This document contains forward-looking statements that are subject to certain
risks, uncertainties and assumptions, including but not limited to, the
outcome of the pending arbitration with Maxygen, the Company's need for
additional funds, the ability to raise sufficient funds on acceptable terms,
the technical uncertainty and risks associated with commercialization of the
Company's technology, the Company's reliance on environmental regulations and
the uncertainty of the adoption of any newly proposed regulations, the market
acceptance of the Company's technology, the Company's dependence on
collaboration partners, competition, and the ability to enforce and defend the
Company's patents and proprietary technologies. Should one or more of such
risks and uncertainties materialize, or should underlying assumptions prove
incorrect, actual results may vary materially from those indicated in such
forward-looking statements. For a discussion of such risks and assumptions,
see "Risk Factors" included in the Company's annual report on Form 10-K for
the year ended December 31, 1999.