title: An ATP-independent strategy for amide bond formation in antibiotic biosynthesis.
abstract: A-503083 B, a capuramycin-type antibiotic, contains an L-aminocaprolactam and an unsaturated hexuronic acid that are linked via an amide bond. A putative class C beta-lactamase (CapW) was identified within the biosynthetic gene cluster that-in contrast to the expected beta-lactamase activity-catalyzed an amide-ester exchange reaction to eliminate the L-aminocaprolactam with concomitant generation of a small but significant amount of the glyceryl ester derivative of A-503083 B, suggesting a potential role for an ester intermediate in the biosynthesis of capuramycins. A carboxyl methyltransferase, CapS, was subsequently demonstrated to function as an S-adenosylmethionine-dependent carboxyl methyltransferase to form the methyl ester derivative of A-503083 B. In the presence of free L-aminocaprolactam, CapW efficiently converts the methyl ester to A-503083 B, thereby generating a new amide bond. This ATP-independent amide bond formation using methyl esterification followed by an ester-amide exchange reaction represents an alternative to known strategies of amide bond formation.
authors.affiliation: Bioengineering Research Group I, Process Technology Research Laboratories, Daiichi Sankyo Co., Ltd., Fukushima, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Funabashi
authors.forename: Zhaoyong
authors.initials: Z
authors.lastname: Yang
authors.forename: Koichi
authors.initials: K
authors.lastname: Nonaka
authors.forename: Masahiko
authors.initials: M
authors.lastname: Hosobuchi
authors.forename: Yoko
authors.initials: Y
authors.lastname: Fujita
authors.forename: Tomoyuki
authors.initials: T
authors.lastname: Shibata
authors.forename: Xiuling
authors.initials: X
authors.lastname: Chi
authors.forename: Steven G
authors.initials: SG
authors.lastname: Van Lanen
mesh_terms: D000255:Adenosine Triphosphate / Q000502:physiology*; D000577:Amides / Q000378:metabolism*; D000900:Anti-Bacterial Agents / Q000096:biosynthesis*; D001381:Azepines; D002264:Carboxylic Acids / Q000737:chemistry; D002384:Catalysis; D003001:Cloning, Molecular; D004252:DNA Mutational Analysis; D004269:DNA, Bacterial / Q000235:genetics; D004952:Esters / Q000378:metabolism; D015723:Gene Library; D006868:Hydrolysis; D007700:Kinetics; D008239:Lysine / Q000378:metabolism; D005810:Multigene Family; D011497:Protein O-Methyltransferase / Q000378:metabolism; D013302:Streptomyces / Q000235:genetics* / Q000378:metabolism; D014529:Uridine / Q000031:analogs & derivatives* / Q000096:biosynthesis / Q000235:genetics; D001618:beta-Lactamases / Q000096:biosynthesis / Q000235:genetics
chemical_list: C495801:A 503083 A; D000577:Amides; D000900:Anti-Bacterial Agents; D001381:Azepines; D002264:Carboxylic Acids; D004269:DNA, Bacterial; D004952:Esters; D000255:Adenosine Triphosphate; D011497:Protein O-Methyltransferase; D001618:beta-Lactamases; D008239:Lysine; D014529:Uridine