猪肝儿茶酚-O-甲基转移酶的纯化及性质

The purification and properties of pig-liver catechol-O-methyl transferase.

作者信息

Gulliver P A, Tipton K F

出版信息

Eur J Biochem. 1978 Aug 1;88(2):439-44. doi: 10.1111/j.1432-1033.1978.tb12467.x.

DOI:10.1111/j.1432-1033.1978.tb12467.x

Abstract

A procedure utilising affinity chromatography is described for the large-scale purification of pig-liver catechol-O-methyl transferase. The enzyme prepared by this method appears to be homogeneous by polyacrylamide gel electrophoretic criteria and gel chromatography. It is stable for prolonged periods when stored at -5 degrees C in 20% (v/v) glycerol. The enzyme has a molecular weight of about 23000 and does not appear to be a compound of subunits, or to associate to any appreciable degree. The pH optimum of the enzyme's activity is approximately pH 7.1--7.4, it does not catalyse the methylation of benzimidazole and has a Km of 0.64 mM and 0.056 mM towards 3,4-dihydroxyphenylacetic acid and S-adenosyl-L-methionine, respectively. Amino acid analysis showed the presence of five cysteine residues.

摘要

本文描述了一种利用亲和色谱法大规模纯化猪肝儿茶酚-O-甲基转移酶的方法。通过这种方法制备的酶，根据聚丙烯酰胺凝胶电泳标准和凝胶色谱法显示似乎是纯一的。当在-5℃下于20%（v/v）甘油中储存时，该酶能长时间保持稳定。该酶的分子量约为23000，似乎不是亚基化合物，也没有明显的缔合现象。该酶活性的最适pH约为7.1 - 7.4，它不催化苯并咪唑的甲基化反应，对3,4-二羟基苯乙酸和S-腺苷-L-甲硫氨酸的Km值分别为0.64 mM和0.056 mM。氨基酸分析表明存在五个半胱氨酸残基。