Rhodococcus erythropolis AJ270, a nitrile hydratase/amidase-containing microbial whole-cell catalyst, is able to catalyze the hydrolysis of a number of β-amino-β-phenyl-propionitrile derivatives under very mild conditions to produce the corresponding β-amino acids and β-amino acid amides. Both the efficiency and enantioselectivity of biocatalysis, however, were strongly dependent upon the structures of both nitrile and amide substrates. While biotransformations of racemic 3-amino-3-phenylpropionitrile gave low enantioselectivity, their N-methylated derivatives underwent moderate enantioselective biocatalytic reactions to afford the corresponding S-β-amino acids and R-β-amino acid amides. N-Bulky group substitution dra-matically slowed down the biotransformations.

Key words: nitrile hydratase, β-amino acid amide, amidase, β-amino acid, enantioselective biotransformation