Kosinostatin(KST)contains an uncommon aminopyrrole moiety,whose biosynthesis has remained elusive.Herein,aminopyrrolinic acid,which was generated by an L-ectoine synthase-like enzyme KstB3 via cyclization of L-glutami...Kosinostatin(KST)contains an uncommon aminopyrrole moiety,whose biosynthesis has remained elusive.Herein,aminopyrrolinic acid,which was generated by an L-ectoine synthase-like enzyme KstB3 via cyclization of L-glutamine,was identified to be the real substrate of adenylation enzyme KstB1.Subsequently,a FAD-dependent dehydrogenase KstB4 along with a transglutaminase-like enzyme KstB6 were also involved in formation of aminopyrrole.These results provided an unusual pathway for 2-aminopyrrole formation in KST biosynthesis.展开更多
of main observation and conclusion Trioxacarcin A(TXN-A)is a polycyclic aromatic natural product with remarkable biological activity.TxnB11,a membrane-bound O-acetyltransferase involved in TXN-A biosynthesis that is d...of main observation and conclusion Trioxacarcin A(TXN-A)is a polycyclic aromatic natural product with remarkable biological activity.TxnB11,a membrane-bound O-acetyltransferase involved in TXN-A biosynthesis that is difficult for protein manipulation,is biochemically characterized here for its acetylation function on C4-sugar.A proposed catalytic mechanism is supported by transmembrane helix analysis and site-directed mutagenesis,in which four conserved amino acid residues His35,Ser71,His1OO and His317 are essential for enzyme activity.We tested the substrate tolerance of TxnB11 to acyl donors in vitro and found that TxnB11 can also utilize propionyl-CoA and glycolyl-CoA,resulting in two new TXN analogs with anti-tumor activity.This work provides a first understanding of the catalytic mechanism of this unusual acyltransferase family and presents good candidates for creating structural diversity for natural products.展开更多
基金We thank Prof.Zixin Deng's Lab.at Shanghai Jiao Tong University and Dr.Chao Peng of the Mass Spectrometry System at the National Facility for Protein Science in Shanghai(NFPS),Zhangjiang Lab,China for obtaining MS data of proteins.Supporting grants including the National Natural Science Foundation of China(21632007 and 21621002)the Chinese Academy of Sciences(QYZDJ-SSW-SLH037)+1 种基金the Academy of Finland(285971)the Sigrid Juselius Foundation are highly acknowledged.
文摘Kosinostatin(KST)contains an uncommon aminopyrrole moiety,whose biosynthesis has remained elusive.Herein,aminopyrrolinic acid,which was generated by an L-ectoine synthase-like enzyme KstB3 via cyclization of L-glutamine,was identified to be the real substrate of adenylation enzyme KstB1.Subsequently,a FAD-dependent dehydrogenase KstB4 along with a transglutaminase-like enzyme KstB6 were also involved in formation of aminopyrrole.These results provided an unusual pathway for 2-aminopyrrole formation in KST biosynthesis.
基金We thank the supporting grants from the NNSFC(Nos.21632007 and 21621002)the CAS(No.XDB20000000 and K.c.wong Education Foundation).
文摘of main observation and conclusion Trioxacarcin A(TXN-A)is a polycyclic aromatic natural product with remarkable biological activity.TxnB11,a membrane-bound O-acetyltransferase involved in TXN-A biosynthesis that is difficult for protein manipulation,is biochemically characterized here for its acetylation function on C4-sugar.A proposed catalytic mechanism is supported by transmembrane helix analysis and site-directed mutagenesis,in which four conserved amino acid residues His35,Ser71,His1OO and His317 are essential for enzyme activity.We tested the substrate tolerance of TxnB11 to acyl donors in vitro and found that TxnB11 can also utilize propionyl-CoA and glycolyl-CoA,resulting in two new TXN analogs with anti-tumor activity.This work provides a first understanding of the catalytic mechanism of this unusual acyltransferase family and presents good candidates for creating structural diversity for natural products.
