title: An enzyme library approach to biocatalysis: development of nitrilases for enantioselective production of carboxylic acid derivatives.
abstract: The discovery, from Nature, of a large and diverse set of nitrilases is reported. The utility of this nitrilase library for identifying enzymes that catalyze efficient production of valuable hydroxy carboxylic acid derivatives is demonstrated. Unprecedented enantioselectivity and substrate scope are highlighted for three newly discovered and distinct nitrilases. For example, a wide array of (R)-mandelic acid derivatives and analogues were produced with high rates, yields, and enantiomeric excesses (95-99% ee). We also have found nitrilases that provide direct access to (S)-phenyllactic acid and other aryllactic acid derivatives, again with high yields and enantioselectivities. Finally, different nitrilases have been discovered that catalyze enantiotopic hydrolysis of 3-hydroxyglutaronitrile to afford either enantiomer of 4-cyano-3-hydroxybutyric acid with high enantiomeric excesses (>95% ee). The first enzymes are reported that effect this transformation to furnish the (R)-4-cyano-3-hydroxybutyric acid which is a precursor to the blockbuster drug Lipitor.
authors.affiliation: Diversa Corporation, 4955 Directors Place, San Diego, California 92121, USA. gdesantis@diversa.com
authors.forename: Grace
authors.initials: G
authors.lastname: DeSantis
authors.forename: Zuolin
authors.initials: Z
authors.lastname: Zhu
authors.forename: William A
authors.initials: WA
authors.lastname: Greenberg
authors.forename: Kelvin
authors.initials: K
authors.lastname: Wong
authors.forename: Jenny
authors.initials: J
authors.lastname: Chaplin
authors.forename: Sarah R
authors.initials: SR
authors.lastname: Hanson
authors.forename: Bob
authors.initials: B
authors.lastname: Farwell
authors.forename: Lawrence W
authors.initials: LW
authors.lastname: Nicholson
authors.forename: Cynthia L
authors.initials: CL
authors.lastname: Rand
authors.forename: David P
authors.initials: DP
authors.lastname: Weiner
authors.forename: Dan E
authors.initials: DE
authors.lastname: Robertson
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Burk
mesh_terms: D000619:Aminohydrolases / Q000737:chemistry* / Q000235:genetics*; D002264:Carboxylic Acids / Q000138:chemical synthesis* / Q000737:chemistry; D002384:Catalysis; D015723:Gene Library; D006868:Hydrolysis; D006880:Hydroxy Acids / Q000138:chemical synthesis; D007773:Lactates / Q000138:chemical synthesis; D008333:Mandelic Acids / Q000138:chemical synthesis; D013237:Stereoisomerism
chemical_list: D002264:Carboxylic Acids; D006880:Hydroxy Acids; D007773:Lactates; D008333:Mandelic Acids; D000619:Aminohydrolases; C021867:nitrilase