RESOLUTION AND SOME PROPERTIES OF ENZYMES INVOLVED IN ENANTIOSELECTIVE TRANSFORMATION OF 1,3-DICHLORO-2-PROPANOL TO (R)-3-CHLORO-1,2-PROPANEDIOL BY CORYNEBACTERIUM SP STRAIN N-1074

During the course of the transformation of 1,3-dichloro-2-propanol (DCP) into (R)-3-chloro-1,2-propanediol [(R)-MCP] with the cell extract of Corynebacterium sp. strain N-1074, epichlorohydrin (ECH) was transiently formed. The cell extract was fractionated into two DCP-dechlorinating activities (fractions I(a) and I(b)) and two ECH-hydrolyzing activities (fractions II(a) and II(b)) by TSKgel DEAE-5PW column chromatography. Fractions I(a) and I(b) catalyzed the interconversion of DCP to ECH, and fractions II(a) and II(b) catalyzed the transformation of ECH into MCP. Fractions I(a) and II(b) showed only low enantioselectivity for each reaction, whereas fractions I(b) and II(b) exhibited considerable enantioselectivity, yielding R-rich ECH and MCP, respectively. Enzymes I(a) and I(b) were isolated from fractions I(a) and I(b), respectively. Enzyme I(a) had a molecular mass of about 108 kDa and consisted of four subunits identical in molecular mass (about 28 kDa). Enzyme I(b) was a protein of 115 kDa, composed of two different polypeptides (about 35 and 32 kDa). The specific activity of enzyme I(b) for DCP was about 30-fold higher than that of enzyme I(a). Both enzymes catalyzed the transformation of several halohydrins into the corresponding epoxides with liberation of halides and its reverse reaction. Their substrate specificities and immunological properties differed from each other. Enzyme I(a) seemed to be halohydrin hydrogen-halide-lyase which was already purified from Escherichia coli carrying a gene from Corynebacterium sp. strain N-1074.