Screening, isolation and taxonomical properties of microorganisms having acrylonitrile-hydrating attivity.

Abstract

Acrylonitrile-hydrating activity was found in various bacteria belonging to the genera Arthrobacter, Corynebacterium, Microbacterium, Nocardia, Pseudomonas and Rhodococcus. A strain, N-774, isolated by acetonitrile enrichment culture from soil showed the highest activity. Taxonomic studies indicated that strain N-774 belonged to the genus Rhodococcus. The acrylonitrile-hydrating enzyme of strain N-774 was constitutively formed in the cells. Besides acrylonitrile, many nitriles were hydrated to the corresponding amides. «-Butyronitrile, suc- cinonitrile and chloroacetonitrille served as suitable substrates. This bacterium could utilize many aliphatic nitriles and amides as a sole source of nitrogen but hardly utilized malononitrile, acrylonitrile or acrylamide. Cells having high nitrile hydratase activity (about 50units/mg of dry cells) could be easily prepared by cultivation at 30°C for 40 hr in a malt extract and yeast extract medium.