Synechococcus sp. Strain WH8102藻红蛋白裂合酶CpeY、CpeZ的克隆、表达及功能研究  

Cloning,Expression,and Functions of the Phycoerythrin Lyases CpeY and CpeZ in Synechococcus sp. WH8102

作　　者：伍贤军[1] 王志斌[1] 赵开弘[2] 周明[2] 

机构地区：[1]华中科技大学环境科学与工程学院,武汉430074 [2]华中农业大学农业微生物国家重点实验室,武汉430070

出　　处：《植物科学学报》2012年第6期591-598,共8页Plant Science Journal

基　　金：国家自然科学基金资助项目(30870519;21072068)

摘　　要：通过蛋白质序列相似性分析,在Synechococcus sp.strain WH8102里面找到了与Fremyella diplosiphon的藻红蛋白裂合酶编码基因cpeY、cpeZ同源的基因SYNW2013、SYNW2012,分别命名为cpeY-Syn、cpeZ-Syn。通过分子克隆技术,将其构建在不同的表达载体上。通过大肠杆菌体内表达系统,藻红胆素(PEB)在CpeY-Syn和CpeZ-Syn的共同催化下,共价连接到藻红蛋白α亚基脱辅助基蛋白CpeA上,生成色素蛋白PEB-CpeA。实验也表明,在缺少CpeY-Syn的情况下,不能产生色素蛋白,而在缺少CpeZ-Syn的情况下,色素蛋白产率有所降低。与CpcE/F催化藻蓝蛋白α亚基共价连接藻蓝胆素(PCB)一样,CpeY/Z-Syn专一性的催化藻红蛋白α亚基与PEB的连接,它们属于同一类的蛋白家族。Based on homology analysis of amino acid sequences,SYNW2013 and SYNW2012 from Synechococcus sp.WH8102 were found,which were similar to CpeY and CpeZ from Fremyella diplosiphon.The respective genes are named as cpeY-Syn and cpeZ-Syn,and were then constructed into different expression vectors via molecular cloning techniques.Using a heterologous coexpression system in Escherichia coli,CpeY-Syn and CpeZ-Syn could cooperatively catalyze the covalent attachment of phycoerythrobilin to CpeA.The experiments also showed that CpeY-Syn alone could ligate phycoerythrobilin to CpeA,but the yield of PEB-CpeA was lower than that in the presence of both CpeY-Syn and CpeZ-Syn.No fluorescent products were observed in the absence of CpeY-Syn.Similar to the CpcE/F lyases,which are responsible for the covalent attachment of phycocyanobilin to CpcA,the CpeY/Z-Syn lyases exclusively catalyzed the covalent attachment of phycoerythrobilin to CpeA.They belong to the E/F type of lyases of phycobiliproteins.

关 键 词：裂合酶 藻红蛋白 共表达 

分 类 号：Q71[生物学—分子生物学]