Rhodococcus sp. AJ270, a powerful and versatile nitrile hydratase/amidase containing microbial whole-cell system, catalyzed the enantioselective hydrolysis of both racemic trans- and cis-2-arylcyclopropanecarbonitriles to afford the corresponding amides and acids with enantiomeric excesses as high as >99%. The reaction rate and enantioselectivity observed for both nitrile hydratase and amidase were also strongly dependent upon the nature of the substituent and substitution pattern on the benzene ring of the substrates. The application of and the advantages of biotransformation of nitriles were demonstrated by preparing (1S,2R)-2-phenylcyclopropylamine and (1R,2R)-2-phenylcyclopropylmethylamine through facile and straightforward chemical manipulations of (1S,2S)-2-phenylcyclopropanecarboxylic acid and (1R,2R)-2-phenylcyclopropanecarboxamide, respectively.