Nitrilase Activity Screening on Structurally Diverse Substrates: Providing Biocatalytic Tools for Organic Synthesis
Résumé
A high-throughput screening of candidate
nitrilases against 25 structurally diverse substrates allowed
us to create a wide collection of 125 experimentally
validated nitrilases. The enzymes were selected
by genomic approach from 700 diverse prokaryotic
species and one metagenome as representative
of the nitrilase family diversity. The enzymatic
screening of this collection expands the biocatalytic
toolbox for chemical synthesis by providing a large
number of tested nitrilases with their assigned substrates.
Three examples illustrate the synthetic potential
of our enzyme collection. The syntheses of carboxylic
acid building blocks, a b-substituted phenylpropanoic
acid, a cyclic g-keto carboxylic acid and
a mononitrile monocarboxylic acid, were achieved
from the corresponding nitrile substrates, using three
new nitrilases (two from Sphingomonas wittichii and
one from Syntrophobacter fumaroxidans). Improvements
of nitrilase activities through the optimization
of reaction parameters and the preparative biocatalytic
synthesis are presented for these three examples.