重组凝乳酶原在大肠杆菌中的表达及活性研究  

Expression of recombinant prochymosin in E.coli and research on its activity

作　　者：李新苹[1] 刘欢欢[1] 普燕[1] 张富春[1] 李轶杰[1] 

机构地区：[1]新疆大学生命科学与技术学院,乌鲁木齐830046

出　　处：《中国乳品工业》2011年第9期14-16,27,共4页China Dairy Industry

基　　金：国家自然科学基金资助(30860265);新疆生物资源基因工程重点实验室基金(XJDX0201-2010-2)

摘　　要：为了提高干酪生产中起重要凝乳作用的凝乳酶的原核表达效率,分析了Genbank中牛、羊和骆驼凝乳酶原(prochymosin,pCHY)的保守序列及大肠杆菌密码子的偏爱性,合成了凝乳酶原序列,并将其克隆至大肠杆菌原核表达载体上。经IPTG的诱导得到高效表达的凝乳酶原;Western blotting检测证明了其具有免疫原性;经pH值2到6活化后成功自剪切,得到大小约36 ku的有凝乳活性的凝乳酶。研究获得较高表达水平具有凝乳活性的重组凝乳酶。Chymosin plays an important role in clotting milk when manufacturing cheese. Aim to improve the expression of recombinant chymosin, we analyzed the conserve sequence of buffalo, lamb, camel in Genbank and the optimal codons of E.coli, synthesized the sequence of prochymosin. The gene encoding prochymosin has been cloned and hyperexpressed in E.coli BL21 （DE3） after IPTG induction. Western blotting indicates the prochymosin protein has antigenicity. SDS-PAGE shows it could autocatalytically clip at acidic pH, and activited chymosin which is about 36 ku shows milk clotting activity. The recombinant chymosin which could make milk clotting has high level expression.

关 键 词：凝乳酶原 密码子优化 凝乳活性 

分 类 号：Q789[生物学—分子生物学] Q936