Catalyzed by Rhodococus sp. AJ270 whole cells, meso-dinitriles such as both endo-and exo-bicyclo[2.2.1]-5-heptene-2,3-dinitriles and - bicyclo[2.2.2]-5-octen-2,3-dinitriles were transformed into the corresponding dicarboxylic acids or their anhydrides whilst the racemic trans-bicyclo[2.2.1]-5-heptene-2,3-dinitrile and trans- bicyclo[2.2.2]-5-octene-2,3-dinitrile were converted regioselectiviely and stereoselectively to give the optically active monocyano amide and acid. The pattern of the nitrile hydratase action on the dinitrile substrates was also discussed.

Key words: SELECTIVITY, HYDROLYSIS, ITRILE-HYDRATASE, AMIDES P, HYDROLASE