在大肠杆菌细胞中表达的重组酵母外切-β-1,3-葡聚糖酶（Exg 1p）的特性分析。

Characterization of recombinant yeast exo-beta-1,3-glucanase (Exg 1p) expressed in Escherichia coli cells.

作者信息

Suzuki K, Yabe T, Maruyama Y, Abe K, Nakajima T

机构信息

Divison of Applied Life Science, Graduate School of Agricultural Science, Tohoku University, Sendai, Japan.

出版信息

Biosci Biotechnol Biochem. 2001 Jun;65(6):1310-4. doi: 10.1271/bbb.65.1310.

DOI:10.1271/bbb.65.1310

PMID:11471729

Abstract

Yeast exo-beta-1,3-glucanase gene (EXG1) was expressed in Escherichia coli and the recombinant enzyme (Exg1p) was characterized. The recombinant Exglp had an apparent molecular mass of 45 kDa by SDS-PAGE and the enzyme has a broad specificity for beta-1,3-linkages as well as beta-1,6-linkages, and also for other beta-glucosidic linked substrates, such as cellobiose and pNPG. Kinetic analyses indicate that the enzyme prefers small substrates such as laminaribiose, gentiobiose, and pNPG rather than polysaccharide substrates, such as laminaran or pustulan. With a high concentration of laminaribiose, the enzyme catalyzed transglucosidation forming laminarioligosaccharides. The enzyme was strongly inhibited with high concentrations of laminaran.

摘要

酵母外切β-1,3-葡聚糖酶基因（EXG1）在大肠杆菌中表达，并对重组酶（Exg1p）进行了特性分析。通过SDS-PAGE分析，重组Exglp的表观分子量为45 kDa，该酶对β-1,3-连接以及β-1,6-连接具有广泛的特异性，对其他β-糖苷连接的底物，如纤维二糖和对硝基苯-β-D-葡萄糖苷（pNPG）也具有活性。动力学分析表明，该酶更倾向于小分子底物，如昆布二糖、龙胆二糖和pNPG，而不是多糖底物，如海带多糖或普鲁兰多糖。在高浓度昆布二糖存在下，该酶催化转糖基化反应形成昆布寡糖。高浓度的海带多糖对该酶有强烈的抑制作用。