Overexpressing codon-adapted fusion proteins of 4-coumaroyl-CoA ligase (4CL) and stilbene synthase (STS) for resveratrol production in Chlamydomonas reinhardtii

Resveratrol is a plant phenolic secondary metabolite derived from phenylpropane metabolic pathway. It is a phytoalexin of high pharmaceutical interest produced in the defense response of plants. To produce resveratrol in Chlamydomonas reinhardtii , 4-coumaroyl-CoA ligase (4CL) and stilbene synthase (STS), two enzymes in the last two steps of resveratrol synthesis in higher plants, were fused together by a glycine–serine–glycine (GSG) tripeptide linker after codon adaptation according to the genome of C. reinhardtii . The fusion protein 4CL-GSG-STS was overexpressed in a wild-type (CC125) and a wall-deficient C. reinhardtii (CC 425). A high level of resveratrol accumulation (22.8 μg g −1 , dry weight) was obtained in CC125 transformed with codon-adapted 4CL-GSG-STS after supplementary of cinnamic acid in the culture medium.