Combinational biosynthesis of phycocyanobilin using genetically-engineered Escherichia coli

摘要

Genes of the key enzymes for phycocyanobilin (PCB) biosynthesis were cloned into E. coli and combinationally expressed to produce phycocyanobilin, with autologous heme as substrate. Culture conditions were optimized to achieve similar to 3 mg PCB/l. A protocol for the purification of recombinant phycocyanobilin was established using solvent extraction combined with chromatography, which resulted in a final yield of similar to 0.3 mg PCB/l with a purity > 95 %. Recombinant phycocyanobilin could scavenge hydroxyl radicals with an EC50 of 0.1 mu M.