木薯中肌醇半乳糖苷合成酶基因在大肠杆菌中的表达

Expression of Recombinant Galactinol Synthase of Manihot esculenta Crantz in Escherichia coli

本研究利用从木薯中克隆到的肌醇半乳糖苷合成酶基因构建到高效表达载体pGEX-6p-1上,构建重组载体MeGolS5-p GEX,并对GST-MeGolS5融合表达的IPTG诱导浓度、诱导不同温度、不同菌液浓度和诱导时间等条件进行优化。研究结果表明:随诱导时间增长GST-MeGolS5融合蛋白表达量提高,在37℃时,OD600为0.4左右,诱导4 h MeGolS5-GST融合蛋白的表达量达到最大,在0.2 mmol/L IPTG浓度下,可以有效诱导MeGolS5-GST融合蛋白的表达;MeGolS5重组菌株可以耐受5%的PEG6000模拟的干旱胁迫。本研究结果可为解析MeGolS5基因的功能以及在木薯抗旱过程中的作用机理提供参考。

Abs tract A full-length galactinol synthase gene sequence of cassava has been cloned into the high expression vector p GEX-6p-1, and named as MeGolS5-p GEX. The GST-MeGolS5 fusion protein was expressed induced by IPTG. The expression conditions such as IPTG concentration, bacterium concentration, induction time and temperature were optimized. The results showed that the expression level of GST-MeGolS5 was increased by accompanying with the induction time. In the condition of 37℃, OD600 is 0.4 and cultured 4 hours, GST-MeGolS5 fusion protein reached the highest expression. 0.2 mmol/L concentration of IPTG can induce GST-MeGolS5 expression effectively in Escherichia coli expression system. The aim of this research was to analyze the function and drought tolerance mechanism of MeGolS5 gene.