Droba B, Droba M
Department of Basic Natural Sciences, Agricultural Academy, Rzeszów, Poland.
Folia Biol (Krakow). 1992;40(1-2):67-71.
Two forms (I and II) of beta-N-acetyl-D-glucosaminidase from cock seminal plasma and one form (III) from spermatozoa were separated by chromatofocusing. The active enzyme forms I and II had pI values of 6.6 and 6.3, respectively, while form III had two subforms with pI values of 6.3 and 6.1, as determined by polyacrylamide gel electrofocusing. The molecular weights were 76,000 for forms I and III and 32,000 for form II. The optimum pH of enzyme forms I and III ranged from 3.6 to 4.0. In contrast, form II showed one distinct maximum at pH 3.7. The Km values obtained with p-nitrophenyl-beta-N-acetyl-D-glucosaminide as substrate were 0.35, 0.28, and 0.39 mM for forms I, II, and III, respectively. It is assumed that both cock spermatozoa and cock seminal plasma contain a common, enzymatically active beta-N-acetyl-D-glucosaminidase subunit with M(r) about 32,000 and pI 6.3.
通过色谱聚焦法分离了来自公鸡精浆的两种形式（I和II）的β-N-乙酰-D-氨基葡萄糖苷酶以及来自精子的一种形式（III）。通过聚丙烯酰胺凝胶电聚焦测定，活性酶形式I和II的pI值分别为6.6和6.3，而形式III有两种亚形式，pI值分别为6.3和6.1。形式I和III的分子量为76,000，形式II的分子量为32,000。酶形式I和III的最适pH范围为3.6至4.0。相比之下，形式II在pH 3.7时显示出一个明显的峰值。以对硝基苯基-β-N-乙酰-D-氨基葡萄糖苷为底物时，形式I、II和III的Km值分别为0.35、0.28和0.39 mM。据推测，公鸡精子和公鸡精浆都含有一种常见的、具有酶活性的β-N-乙酰-D-氨基葡萄糖苷酶亚基，其分子量约为32,000，pI为6.3。
