HUMAN-LIVER CATHEPSIN-L
HUMAN-LIVER CATHEPSIN-L
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DOI：
10.1042/bj2260233
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发表时间：
1985-01-01
影响因子：
4.1
通讯作者：
BARRETT, AJ
中科院分区：
文献类型：
--
作者：
MASON, RW;GREEN, GDJ;BARRETT, AJ
从死后获得的人肝脏中纯化组织蛋白酶L至表观均一性。有必要在pH4.2和37 ℃下处理匀浆。C释放活性酶。纯化过程涉及在羧甲基葡聚糖凝胶和Pharmacia快速蛋白质液相色谱系统的Mono S柱上的离子交换色谱。该酶由分子量为25，000和5000的两条多肽链组成。较大的链被证明含有活性位点的半胱氨酸残基。人组织蛋白酶L被证明是类似的大鼠和兔酶的动力学常数为底物苄氧羰基苯丙氨酰精氨酸7-（4-甲基）香豆酰胺和失活率的活性位点定向试剂苄氧羰基苯丙氨酰苯丙氨酰重氮甲烷和苄氧羰基苯丙氨酰丙氨酰重氮甲烷。因此，组织蛋白酶L的明确特征现在正在出现，这些应该简化在其他组织和物种中的酶的鉴定。
Cathepsin L was purified to apparent homogeneity from human liver obtained post mortem. It was necessary to treat the homogenate at pH 4.2 and 37.degree. C to release active enzyme. The purification procedure involved ion-exchange chromatography on carboxymethyl-Sephadex and the Mono S column of a Pharmacia fast-protein-liquid-chromatography system. The enzyme consists of 2 polypeptide chains of MW 25,000 and 5000. The larger chain was shown to contain the active-site cysteine residue. Human cathepsin L proved to be similar to the rat and rabbit enzymes in regard to kinetic constants for the substrate benzyloxycarbonylphenylalanylarginine 7-(4-methyl)coumarylamide and rates of inactivation by the active-site-directed reagents benzyloxycarbonylphenylalanylphenylalanyldiazomethane and benzyloxycarbonylphenylalanylalanyldiazomethane. Thus clear characteristics of cathepsin L are now emerging, and these should simplify the identification of the enzyme in other tissues and species.