화학공학소재연구정보센터
Applied Microbiology and Biotechnology, Vol.42, No.1, 1-7, 1994
Enantioselective Hydrolysis of Racemic 2-Phenylpropionitrile and Other (R,S)-2-Arylpropionitriles by a New Bacterial Isolate, Agrobacterium-Tumefaciens Strain D3
Bacteria were enriched from soil samples with succinate as carbon source and racemic 2-phenylpropionitrile as sole source of nitrogen. One of the isolates, strain d3, converted (R,S)-2-phenylpropionitrile with high enantioselectivity to (S)-2-phenylpropionic acid. Strain d3 was identified as Agrobacterium tumefaciens. Resting cells hydrolysed 2-phenylpropionitrile via 2-phenylpropionamide to 2-phenylpropionic acid. Racemic 2-phenylpropionitrile as well as 2-phenylpropionamide were converted to (S)-2-phenylpropionic acid with an enantiomeric excess above 96%. The nitrile hydratase and the amidase were both shown to convert preferentially the S enantiomer of their respective substrate. These two enzymes were induced in the presence of (R,S)-2-phenylpropionitrile but only in the absence of ammonia. In addition to 2-phenylpropionitrile strain d3 could utilize various aliphatic and aromatic nitriles as nitrogen sources. Resting cells of strain d3 also converted (R,S)-2-phenylbutyronitrile, ibuprofen nitrile, ketoprofen nitrile and alpha-aminophenylacetonitrile with high enantioselectivity. The nitrile- and amide-converting enzyme activities were also found in cell-free extracts.