甜蛋白Monellin基因在大肠杆菌中的高效表达  

Overexpression of a Sweet Protein Monellin in Escherichia coli

作　　者：陈忠军[1] 蔡恒[1] 路福平[1] 杜连祥[1] 

机构地区：[1]天津市工业微生物重点实验室,天津科技大学生物工程学院,天津300222

出　　处：《生物工程学报》2005年第4期568-572,共5页Chinese Journal of Biotechnology

摘　　要：根据已报道的单链monellin甜蛋白的氨基酸序列,采用细菌偏爱密码子,人工合成了全长294bp的monellin基因。插入到大肠杆菌表达载体pET_22b中,构建重组分泌型表达载体pETMO。经IPTG诱导pETMO所含有的甜蛋白基因可在大肠杆菌BL21(DE3)中高效表达,表达量占菌体可溶性蛋白的44·8%。且经纯化后测定其甜度是蔗糖的3000倍。得到的甜蛋白热稳性及耐酸性均比天然产物有所提高。According to the amino acid sequence of monellin, a single chain 294bp monellin gene was synthesized and inserted into vector pET-22b to yield the recombinant secretion plasmid pETMO. The single-chain monellin gene was designed based on the biased codons of E.coli so that its expression would be then optimized. Under the expressing conditions, monellin was produced accounting for 44.8% of total soluble proteins. The E.coli-expressed single-chain monellin is 3000 times sweeter than sucrose. The thermal-stability and acid-resistance of the protein are higher than the natural monellin.

关 键 词：甜蛋白 Monellin基因 大肠杆菌 基因表达 热稳性 耐酸性 细菌优化密码子 食品添加剂 饲料添加剂 

分 类 号：Q786[生物学—分子生物学]