Nitrilase Activity Screening on Structurally Diverse Substrates: Providing Biocatalytic Tools for Organic Synthesis

International audienceA high-throughput screening of candidatenitrilases against 25 structurally diverse substrates allowedus to create a wide collection of 125 experimentallyvalidated nitrilases. The enzymes were selectedby genomic approach from 700 diverse prokaryoticspecies and one metagenome as representativeof the nitrilase family diversity. The enzymaticscreening of this collection expands the biocatalytictoolbox for chemical synthesis by providing a largenumber of tested nitrilases with their assigned substrates.Three examples illustrate the synthetic potentialof our enzyme collection. The syntheses of carboxylicacid building blocks, a b-substituted phenylpropanoicacid, a cyclic g-keto carboxylic acid anda mononitrile monocarboxylic acid, were achievedfrom the corresponding nitrile substrates, using threenew nitrilases (two from Sphingomonas wittichii andone from Syntrophobacter fumaroxidans). Improvementsof nitrilase activities through the optimizationof reaction parameters and the preparative biocatalyticsynthesis are presented for these three examples