从日本曲霉中提取β-呋喃果糖苷酶的纯化和性质。

Purification and properties ofβ-fructofuranosidase from Aspergillus japonicus.

机构信息

Department of Industrial Chemistry, Faculty of Engineering, Miyazaki University, 1-1 Gakuen Kibanadai Nishi, 889-21, Miyazaki, Japan.

出版信息

World J Microbiol Biotechnol. 1992 May;8(3):276-9. doi: 10.1007/BF01201878.

DOI:10.1007/BF01201878

PMID:24425477

Abstract

β-Fructofuranosidase fromAspergillus japonicus, which produces 1-kestose (O-β-D-fructofuranosyl-(2→1)-β-D-fructofuranosyl α-D-glucopyranoside) and nystose (O-β-D-fructofuranosyl-(2→1)-β-D-fructofuranosyl-(2→1)-β-D-fructofuranosyl α-D-glucopyranoside) from sucrose, was purified to homogeneity by fractionation with calcium acetate and ammonium sulphate and chromatography with DEAE-Cellulofine and Sephadex G-200. Its molecular size was estimated to be about 304,000 Da by gel filtration. The enzyme was a glycoprotein which contained about 20% (w/w) carbohydrate. Optimum pH for the enzymatic reaction was 5.5 to 6. The enzyme was stable over a wide pH range, from pH 4 to 9. Optimum reaction temperature for the enzyme was 60 to 65°C and it was stable below 60°C. The Km value for sucrose was 0.21M. The enzyme was inhibited by metal ions, such as those of silver, lead and iron, and also byp-chloromercuribenzoate.

摘要

米曲霉β-呋喃果糖苷酶能将蔗糖分解为棉子糖（O-β-D-呋喃果糖基-(2→1)-β-D-呋喃果糖基-α-D-吡喃葡萄糖苷）和昆布二糖（O-β-D-呋喃果糖基-(2→1)-β-D-呋喃果糖基-(2→1)-β-D-呋喃果糖基-α-D-吡喃葡萄糖苷），本研究通过乙酸钙和硫酸铵分级、DEAE-纤维素和 Sephadex G-200 层析对其进行了纯化，获得了均一性酶制剂。凝胶过滤法估计该酶的分子大小约为 304,000 Da。该酶是一种糖蛋白，含有约 20%（w/w）的碳水化合物。酶促反应的最适 pH 值为 5.5 至 6。该酶在较宽的 pH 范围内稳定，pH 值为 4 至 9。该酶的最适反应温度为 60 至 65°C，低于 60°C 时稳定。蔗糖的 Km 值为 0.21M。该酶被银、铅和铁等金属离子以及对氯汞苯甲酸抑制。