Flavin-dependent halogenases (FDHs) are well known to introduce carbon halide bonds (mainly C–Cl and C–Br) into natural products with the assistance of a partner protein flavin reductase to generate reduced flavin (...Flavin-dependent halogenases (FDHs) are well known to introduce carbon halide bonds (mainly C–Cl and C–Br) into natural products with the assistance of a partner protein flavin reductase to generate reduced flavin (FADH_(2)or FMNH_(2)).Compared with the common chloride-and bromide-containing natural products (approximately 5,000 compounds),iodinated natural products(approximately 100 compounds) are very limited.Specific iodinases have also rarely been identified in nature to date.This study discovered a novel relationship between iodination and flavin reductases for the first time.Through mechanistic studies,it was identified that peroxide (H_(2)O_(2)) was released from the uncoupling reaction of flavin reductases and then reacted with iodide ions(I^(-)) to produce hypoiodous acid (IOH) for the final iodination.Furthermore,this study also unintentionally verified that the recently reported flavin-dependent iodinase Vir X1 from the marine virus and its two homologs (MBG and NCV) did not catalyze iodination in the in vitro biochemical system but likely belonged to a new phylogenetic clade in the tryptophan halogenase superfamily.As a consequence,actual flavin-dependent iodinases in nature remain to be discovered by the scientific community in the future.展开更多
基金the National Natural Science Foundation of China(21632007,21661140002 for S.Lin81903525 for Y.Zhang)+1 种基金Research Fund for High-level Talents of Xinxiang Medical University(300-505272)Open Funding Project of State Key Laboratory of Microbial Metabolism,Shanghai Jiao Tong University(MMLKF2011)。
文摘Flavin-dependent halogenases (FDHs) are well known to introduce carbon halide bonds (mainly C–Cl and C–Br) into natural products with the assistance of a partner protein flavin reductase to generate reduced flavin (FADH_(2)or FMNH_(2)).Compared with the common chloride-and bromide-containing natural products (approximately 5,000 compounds),iodinated natural products(approximately 100 compounds) are very limited.Specific iodinases have also rarely been identified in nature to date.This study discovered a novel relationship between iodination and flavin reductases for the first time.Through mechanistic studies,it was identified that peroxide (H_(2)O_(2)) was released from the uncoupling reaction of flavin reductases and then reacted with iodide ions(I^(-)) to produce hypoiodous acid (IOH) for the final iodination.Furthermore,this study also unintentionally verified that the recently reported flavin-dependent iodinase Vir X1 from the marine virus and its two homologs (MBG and NCV) did not catalyze iodination in the in vitro biochemical system but likely belonged to a new phylogenetic clade in the tryptophan halogenase superfamily.As a consequence,actual flavin-dependent iodinases in nature remain to be discovered by the scientific community in the future.