鱼腥藻PCC7120核膜连接蛋白ApcE体内重组研究

In vivo Reconstitution of Anabaena sp.PCC7120 Core-membrane Linker Protein ApcE with Phycocyanobilin

摘要: 为了研究鱼腥藻PCC7120核-膜连接蛋白ApcE(1-240)脱辅基蛋白与藻蓝胆素的连接机制,通过体内重组方式得到色素蛋白PCB-ApcE(1-240)。吸收光谱、荧光光谱分析表明,核-膜连接蛋白ApcE(1-240)与藻蓝胆素进行了正确的体内重组。ApcE(1-240)脱辅基蛋白可与藻蓝胆素体内自催化共价连接,获得的色素蛋白溶于含有4 mol/L尿素的磷酸钾缓冲体系中,并具有最大吸收峰(λ_max=660 nm)和荧光发射峰(λ_max=668 nm)。

Abstract: The deletion mutated core-membrane linker protein ApcE(1-240) from Anabaena sp.PCC7120 were overexpressed in E.coli.The activities of expressed proteins were studied through in vivo reconstitution tests,where phycocyanobilin-biosynthesizing gene(ho1 and pcyA) were transformed into E.coli.Through the absorption and the fluorescence spectra,the results show ApcE(1-240) could bind covalently phycocyanobilin(PCB) in an autocatalytic reaction.The presence of 4 mol/L urea is necessary to solubilize the resulting biliprotein,and it has absorption maxima(λ_max=660 nm) and fluorescence maxima(λ_max=668 nm).