公牛精浆中β-葡萄糖醛酸酶的纯化、特性鉴定及其在受精中的作用。

Purification and characterization of beta-glucuronidase from bull seminal plasma and its role in fertilization.

作者信息

Rethinaswamy A, Yang C H, Srivastava P N

机构信息

Department of Biochemistry, University of Georgia, Athens 30602.

出版信息

Mol Reprod Dev. 1994 Aug;38(4):404-9. doi: 10.1002/mrd.1080380408.

DOI:10.1002/mrd.1080380408

PMID:7980949

Abstract

Bull seminal plasma contains high levels of beta-glucuronidase. The present study describes the isolation and characterization of beta-glucuronidase, and its role in fertilization. beta-glucuronidase was purified by ion exchange chromatography, saccharolactone-agarose affinity chromatography, and gel filtration. The specific activity of the purified enzyme was 4,414 mumoles/mg protein/min. The purified enzyme showed a single band on 7.5% PAGE. On SDS-PAGE, the enzyme appeared to consist of four identical subunits of M(r) 75,000 each. The apparent Km and Vmax for beta-glucuronidase were 0.4 mM and 5.7 mumol/min using phenolpthalein mono-beta-glucuronic acid as the substrate. beta-glucuronidase appeared to accelerate the cumulus dispersion in vitro.

摘要

牛精液浆中含有高水平的β-葡萄糖醛酸酶。本研究描述了β-葡萄糖醛酸酶的分离、特性及其在受精中的作用。通过离子交换色谱、糖内酯-琼脂糖亲和色谱和凝胶过滤对β-葡萄糖醛酸酶进行了纯化。纯化酶的比活性为4414微摩尔/毫克蛋白质/分钟。纯化后的酶在7.5%聚丙烯酰胺凝胶电泳（PAGE）上显示出一条带。在十二烷基硫酸钠-聚丙烯酰胺凝胶电泳（SDS-PAGE）上，该酶似乎由四个相同的亚基组成，每个亚基的相对分子质量（M(r)）为75000。以酚酞单-β-葡萄糖醛酸为底物时，β-葡萄糖醛酸酶的表观米氏常数（Km）和最大反应速度（Vmax）分别为0.4毫摩尔和5.7微摩尔/分钟。β-葡萄糖醛酸酶似乎能在体外加速卵丘扩散。