摘要
用PCR方法从嗜热厌氧乙醇杆菌(Thermoanaerobacter ethanolicus)JW200中扩增出编码a-葡萄糖苷酶的基因,将其克隆到大肠杆菌(Escherichia coli)表达载体pTrc99A上并获得表达a-葡萄糖苷酶的大肠杆菌重组菌。重组菌经IPTG诱导表达,SDS-PAGE检测出蛋白相对分子量约89kDa,经阴离子交换层析和凝胶层析纯化后的a-葡萄糖苷酶最适反应温度为70℃,最适反应pH为5～5.5,且在pH 5.5～6.5之间有较高的稳定性。重组a-葡萄糖苷酶在70℃下105 min后酶活仍达到80%。
The α-glucosidase gene from Thermoanaerobacter ethanolicus JW200 was cloned and expressed in E. coll. The recombinant α-glucosidase was purified by three steps, heat treatment, DEAE-Sephacel and gel filtration chromatography. The purified recombinant enzyme had a molecular mass of 89 kDa on SDS-PAGE. The maximum activity was found at pH 5-5.5 and 70 ℃. The enzyme was stable in the range pH 5.5-6.5, and retained over 80% of its activity after holding for 105 min at 70 ℃
出处
《工业微生物》
CAS
CSCD
2010年第6期60-64,共5页
Industrial Microbiology
