THIOL S-METHYLTRANSFERASE FROM RAT-LIVER

被引:73
作者
WEISIGER, RA [1 ]
JAKOBY, WB [1 ]
机构
[1] NIAMDD, BIOCHEM & METAB LAB, ENZYMES & CELLULAR BIOCHEM SECT, BETHESDA, MD 20014 USA
关键词
D O I
10.1016/0003-9861(79)90317-5
中图分类号
Q5 [生物化学]; Q7 [分子生物学];
学科分类号
071010 ; 081704 ;
摘要
The thiol S-methyltransferase from rat liver has been solubilized and prepared in homogeneous form. The enzyme exists in a monomer of Mr 28,000 although enzyme activity is highly unstable with a half-life of 4 days under the best conditions of storage. The reaction requires S-adenosylmethionine as methyl donor but, as is the case with many enzymes active in detoxification, a large variety of lipophilic compounds can serve as acceptors. Acceptor activity is limited to thiols. The naturally occurring hydrophilic thiols, glutathione and cysteine, act neither as substrates nor as inhibitors. The course of the reaction is biphasic with an initial rapid formation of product that is followed by a slower linear rate. The suggestion is offered that this behavior reflects the slow dissociation of an enzyme-product complex composed of enzyme and S-adenosyl-homocysteine. © 1979.
引用
收藏
页码:631 / 637
页数:7
相关论文
共 17 条