Nakamura T, Nagasawa T, Yu F, Watanabe I, Yamada H
Central Research Laboratory, Nitto Chemical Industry Company, Ltd., Yokohama, Japan.
J Bacteriol. 1992 Dec;174(23):7613-9. doi: 10.1128/jb.174.23.7613-7619.1992.
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 Ia and Ib) and two ECH-hydrolyzing activities (fractions IIa and IIb) by TSKgel DEAE-5PW column chromatography. Fractions Ia and Ib catalyzed the interconversion of DCP to ECH, and fractions IIa and IIb catalyzed the transformation of ECH into MCP. Fractions Ia and IIa showed only low enantioselectivity for each reaction, whereas fractions Ib and IIb exhibited considerable enantioselectivity, yielding R-rich ECH and MCP, respectively. Enzymes Ia and Ib were isolated from fractions Ia and Ib, respectively. Enzyme Ia had a molecular mass of about 108 kDa and consisted of four subunits identical in molecular mass (about 28 kDa). Enzyme Ib was a protein of 115 kDa, composed of two different polypeptides (about 35 and 32 kDa). The specific activity of enzyme Ib for DCP was about 30-fold higher than that of enzyme Ia. 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 Ia seemed to be halohydrin hydrogen-halide-lyase which was already purified from Escherichia coli carrying a gene from Corynebacterium sp. strain N-1074.
在利用棒状杆菌属菌株N - 1074的细胞提取物将1,3 - 二氯 - 2 - 丙醇(DCP)转化为(R)- 3 - 氯 - 1,2 - 丙二醇[(R)- MCP]的过程中,会短暂形成环氧氯丙烷(ECH)。通过TSKgel DEAE - 5PW柱色谱法,将细胞提取物分离为两种DCP脱氯活性组分(组分Ia和Ib)和两种ECH水解活性组分(组分IIa和IIb)。组分Ia和Ib催化DCP与ECH之间的相互转化,组分IIa和IIb催化ECH转化为MCP。组分Ia和IIa对每个反应仅表现出较低的对映选择性,而组分Ib和IIb表现出相当高的对映选择性,分别产生富含R型的ECH和MCP。分别从组分Ia和Ib中分离出酶Ia和酶Ib。酶Ia的分子量约为108 kDa,由四个分子量相同(约28 kDa)的亚基组成。酶Ib是一种115 kDa的蛋白质,由两种不同的多肽(约35 kDa和32 kDa)组成。酶Ib对DCP的比活性比酶Ia高约30倍。两种酶都催化几种卤代醇转化为相应的环氧化物并释放卤化物,以及其逆反应。它们的底物特异性和免疫特性彼此不同。酶Ia似乎是卤代醇卤化氢裂解酶,该酶已从携带棒状杆菌属菌株N - 1074基因的大肠杆菌中纯化得到。