牛脑溶酶体N-乙酰-β-D-己糖胺酶碳水化合物结构的纯化及部分特性分析

Purification and partial characterization of the carbohydrate structure of lysosomal N-acetyl-beta-D-hexosaminidases from bovine brain.

Overdijk B, van Steijn G, Wolf J H, Lisman J J

Int J Biochem. 1982;14(1):25-31. doi: 10.1016/0020-711x(82)90172-0.

Abstract

The lysosomal forms A and B, and an intermediate form I of N-acetyl-beta-D-hexosaminidase (EC 3.2.1.30) were isolated from bovine brain, resulting in the following purification factors and specific activities: hexosaminidase A 20255, 103 U mg-1; hexosaminidase B 34715, 134 U mg-1; hexosaminidase I 15241, 78 U mg-1. 2. The molecular weights of the polypeptide chains were identical for each isoenzyme: two bands of 50 and 53 k daltons were found. 3. Carbohydrate analysis showed the presence of mannose, galactose, N-acetylglucosamine and sialic acid. This composition, and the absence of N-acetylgalactosamine, indicated that only N-glycosidically linked oligosaccharide chains are present. 4. The amino-acid composition showed no substantial differences for the three isoenzymes.

摘要

从牛脑中分离出N - 乙酰 - β - D - 己糖胺酶（EC 3.2.1.30）的溶酶体形式A和B以及中间形式I，得到以下纯化因子和比活性：己糖胺酶A 20255，103 U mg⁻¹；己糖胺酶B 34715，134 U mg⁻¹；己糖胺酶I 15241，78 U mg⁻¹。2. 每种同工酶的多肽链分子量相同：发现了两条分别为50和53千道尔顿的条带。3. 碳水化合物分析表明存在甘露糖、半乳糖、N - 乙酰葡糖胺和唾液酸。这种组成以及不存在N - 乙酰半乳糖胺表明仅存在N - 糖苷键连接的寡糖链。4. 三种同工酶的氨基酸组成没有实质性差异。