链霉菌 A3 中β-葡萄糖苷酶的表达与展示。

Expression and displaying of β-glucosidase from Streptomyces coelicolor A3 in Escherichia coli.

机构信息

Lab of Biosystems and Microanalysis, State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Meilong Rd. 130, Shanghai 200237, China.

出版信息

Appl Biochem Biotechnol. 2013 Aug;170(7):1713-23. doi: 10.1007/s12010-013-0301-4. Epub 2013 May 31.

DOI:10.1007/s12010-013-0301-4

PMID:23722947

Abstract

Two genes encoding β-glucosidase from Streptomyces coelicolor A3(2) were cloned and expressed in Escherichia coli BL21 (DE3). Two recombinant enzymes (SC1059 and SC7558) were purified and characterized. The molecular mass of the purified SC1059 and SC7558 as determined by SDS-PAGE agrees with the calculated values (51.0 and 52.2 kDa, respectively). Optimal temperature and pH for the two enzymes were both at 35 °C and 6.0. SC7558 exhibited to be much more active than SC1059 under optimal conditions, and it was recombined with ice nucleation protein which could anchor on the surface of the cell. The optimal temperature and pH of the recombinant cells were 55 °C and 8.0, respectively. The resultant cells were to be used as material for immobilized β-glucosidase, which is convenient to catalyze substrates in various complicated conditions.

摘要

两个来自链霉菌 A3(2)的编码β-葡萄糖苷酶的基因被克隆并在大肠杆菌 BL21(DE3)中表达。两种重组酶（SC1059 和 SC7558）被纯化并进行了特性分析。通过 SDS-PAGE 测定的纯化 SC1059 和 SC7558 的分子量与计算值相符（分别为 51.0 和 52.2 kDa）。两种酶的最适温度和 pH 值均为 35°C 和 6.0。在最佳条件下，SC7558 的活性明显高于 SC1059，并且它与冰核蛋白重组，可以附着在细胞表面。重组细胞的最适温度和 pH 值分别为 55°C 和 8.0。所得细胞可作为固定化β-葡萄糖苷酶的材料，方便在各种复杂条件下催化底物。