双歧杆菌源亚油酸异构酶的原核表达及功能分析  

Prokaryotic expression and functional analysis of linoleic acid isomerase from Bifidobacterium breve

作　　者：嵇熠彬 梅永超 杨波[1] 陈海琴[1] JI Yibin;MEI Yongchao;YANG Bo;CHEN Haiqin(School of Food Science and Technology,Jiangnan University,Wuxi 214122,China)

机构地区：[1]江南大学食品学院,江苏无锡214122

出　　处：《食品与发酵工业》2023年第23期64-69,共6页Food and Fermentation Industries

基　　金：国家自然科学基金项目(32072186)。

摘　　要：来源于短双歧杆菌CCFM683的亚油酸异构酶(Bifidobacterium breve isomerase,BBI)是目前唯一已知的乳酸菌源单酶转化亚油酸生成共轭亚油酸c9,t11-CLA单体的亚油酸异构酶。该文以pET-28a(+)为表达载体,构建组氨酸标签分别位于C端和N端的重组载体pET-28a(+)-bbi-His和pET-28a(+)-His-bbi,分别实现其在BL21(DE3)、BL21(DE3)pLysS和Rosetta(DE3)3种类型的大肠杆菌(Escherichia coli)宿主中的异源表达和条件优化。结果表明表达BBI的最优重组菌为E.coli Rosetta/pET-28a(+)-bbi-His,最佳诱导条件为以1.0 mmol/L异丙基硫代半乳糖苷诱导8 h,且当用BBI粗酶转化脂肪酸时,相较于亚油酸和γ-亚麻酸,BBI更偏好转化α-亚麻酸。Bifidobacterium breve isomerase(BBI),the linoleic acid isomerase from Bifidobacterium breve CCFM683,is the only known single enzyme from lactic acid bacteria that catalyzes the formation of linoleic acid into cis9,trans11-CLA.Using pET-28a(+)as expression vector to construct recombinant vectors pET-28a(+)-bbi-His and pET-28a(+)-His-bbi with His-tag located at C-terminal and N-terminal,which was heterologous expressed in Escherichia coli BL21(DE3),E.coli BL21(DE3)pLysS and E.coli Rosetta(DE3)respectively.The optimum inductive condition for BBI expression is E.coli Rosetta/pET-28a(+)-bbi-His under the induction of 1.0 mmol/L IPTG for 8 h.BBI prefersα-linolenic acid to linoleic acid andγ-linolenic acid when it catalyzed fatty acid.

关 键 词：大肠杆菌 亚油酸异构酶 共轭脂肪酸 条件优化 底物偏好性 

分 类 号：Q789[生物学—分子生物学]