The entire pathway for the synthesis of a fluorescent holophycobiliprotein subunit from a photosynthetic cyanobacterium was reconstituted in E.coli.Cyanobacterial genes for enzymes ho1 and pcyA were expressed from a plasmid pACYCDuet-ho1-pcyA.Genes for the apoprotein（C-phycocyanin β subunit;cpcB（C155I）） were expressed on a second plasmid pET-cpcB（C155I）.Genes for the lyase（cpeS） that catalyzes chromophore attachment were expressed on a third plasmid pCDFDuet-cpeS.Upon induction

recombinant E.coli used the cellular pool of heme to produce CpcB（C155I）-PCB with spectroscopic properties

qualitatively and quantitatively similar to those of the same protein produced endogenously in cyanobacteria.About 7.56% of the CpcB（C155I） was converted to CpcB（C155I）-PCB in a similarly engineered E.coli strain that lacks cpeS.