人肝组织和血清中核糖核酸酶特性的比较。

Comparison of the properties of ribonucleases in human liver tissue and serum.

作者信息

Tsuji H, Nomiyama K, Murai K, Akagi K, Fujishima M

机构信息

Second Department of Internal Medicine, Faculty of Medicine, Kyushu University, Fukuoka, Japan.

出版信息

Eur J Clin Chem Clin Biochem. 1992 Jun;30(6):339-41.

PMID:1511067

Abstract

Two ribonucleases (RNases) with acidic pH optima were partially purified, one from normal human liver tissue and the other from serum. The properties of the two enzymes were studied and compared. Liver RNase was partially purified about 700-fold by acid fractionation, phosphocellulose column chromatography, Sephadex G-75 gel filtration, and polyguanylate affinity column chromatography. Serum RNase was purified about 1200-fold by phosphocellulose column chromatography and Sephadex G-75 gel filtration. The two RNases showed a similar optimal pH and molecular mass, and similar behaviour towards metal ions, but they differed in their substrate specificity. Liver RNase displayed a higher activity towards polyuridylate (poly(U)) than towards polycytidylate (poly(C)), while serum RNase hydrolysed poly(C) more rapidly than poly(U). These findings suggest that liver RNase is not the primary source of the serum RNase with an acidic pH optimum.

摘要

两种最适pH呈酸性的核糖核酸酶（RNases）被部分纯化，一种来自正常人肝脏组织，另一种来自血清。对这两种酶的性质进行了研究和比较。肝脏核糖核酸酶通过酸分级分离、磷酸纤维素柱色谱、葡聚糖凝胶G-75凝胶过滤和聚鸟苷酸亲和柱色谱被部分纯化了约700倍。血清核糖核酸酶通过磷酸纤维素柱色谱和葡聚糖凝胶G-75凝胶过滤被纯化了约1200倍。这两种核糖核酸酶表现出相似的最适pH和分子量，以及对金属离子的相似行为，但它们在底物特异性方面有所不同。肝脏核糖核酸酶对聚尿苷酸（poly(U)）的活性高于对聚胞苷酸（poly(C)），而血清核糖核酸酶水解聚胞苷酸（poly(C)）的速度比聚尿苷酸（poly(U)）更快。这些发现表明，最适pH呈酸性的血清核糖核酸酶的主要来源不是肝脏核糖核酸酶。