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

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).