摘要
对来自热纤梭菌的纤维素酶CtCel8A的编码基因Ctcel8进行了密码子优化、全基因合成及异源表达。该基因大小为1137 bp,含有379个氨基酸残基,编码理论分子质量为41.8 ku,属于糖苷水解酶GH8家族。该酶能够在大肠杆菌中高效可溶性表达,亲和纯化回收率达69.2%。酶学性质分析结果表明,该酶最适作用温度为70℃,最适pH为5.5,对高温的耐受力较强,但该酶对酸性及碱性环境的耐受力较差。纤维素酶CtCel8A能够有效地切割黄原胶主链,将其水解为中等分子质量产物。
Gene Ctcel8 encoding the cellulase CtCel8A from Clostridium thermofibrillum was codon optimized,gene synthesized and heterologously expressed.The gene sequence encoding CtCel8A is 1137 bp in length.The predicted molecular mass of CtCel8A is 41.8 ku which was composed of 379 amino acid residues.The protein belongs to the glycoside hydrolase(GH)family 8.The enzyme can be highly solubly expressed in Escherichia coli BL21(DE3),and the affinity purification yield was 69.2%.The enzymatic properties showed that the optimum temperature was 70℃and the optimal pH was 5.5.The enzyme had a high tolerance to high temperatures,but had poor tolerance to acidic and alkaline environments.The cellulose CtCel8A can effectively cut the main chain of xanthan and hydrolyze it to products with medium molecular weight.
作者
姜海珠
周海龙
谷金芸
李宪臻
杨帆
JIANG Haizhu;ZHOU Hailong;GU Jinyun;LI Xianzhen;YANG Fan(School of Biological Engineering, Dalian Polytechnic University, Dalian 116034, China;China Biotech Fermentation Industry Association, Beijing 100833, China)
出处
《大连工业大学学报》
CAS
北大核心
2021年第2期79-84,共6页
Journal of Dalian Polytechnic University
基金
国家自然科学基金项目(31671796)
辽宁省高校杰出青年学者成长计划(LJQ2015009)
辽宁省自然科学基金项目(201602059).
关键词
纤维素酶
黄原胶
酶学性质
cellulose
xanthan
enzyme characterization
