title: Precursor-Directed Mutational Biosynthesis Facilitates the Functional Assignment of Two Cytochromes P450 in Thiostrepton Biosynthesis.
abstract: Side-ring-modified thiostrepton (TSR) derivatives that vary in their quinaldic acid (QA) substitution possess more potent biological activities and better pharmaceutical properties than the parent compound. In this work, we sought to introduce fluorine onto C-7' or C-8' of the TSR QA moiety via precursor-directed mutational biosynthesis to obtain new TSR variants. Unexpectedly, instead of the target product, the exogenous chemical feeding of 7-F-QA into the ΔtsrT mutant strain resulted in a unique TSR analog with an incomplete side-ring structure and an unoxidized QA moiety (1). Accordingly, two cytochrome P450 genes, tsrP and tsrR, were in-frame deleted to elucidate the candidate responsible for the monooxidation of the QA moiety in TSR. The unfluorinated analog of compound 1 that was thus isolated from ΔtsrP (2) and the abolishment of TSR production in ΔtsrR revealed not only the biosynthetic logic of the TSR side-ring but also the essential checkpoint in TSR maturation before macro-ring closure.
authors: State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road, Shanghai 200032, China.
authors: Qingfei
authors: Q
authors: Zheng
authors: State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road, Shanghai 200032, China.
authors: Shoufeng
authors: S
authors: Wang
authors: State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road, Shanghai 200032, China.
authors: Rijing
authors: R
authors: Liao
authors: State Key Laboratory of Bioorganic and Natural Products Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences , 345 Lingling Road, Shanghai 200032, China.|Huzhou Center of Bio-Synthetic Innovation , 1366 Hongfeng Road, Huzhou 313000, China.
authors: Wen
authors: W
authors: Liu
mesh_terms: D003577:Cytochrome P-450 Enzyme System / Q000378:metabolism*; D009154:Mutation; D013883:Thiostrepton / Q000096:biosynthesis*
chemical_list: D003577:Cytochrome P-450 Enzyme System; D013883:Thiostrepton