title: Fatty acyl-AMP ligase involvement in the production of alkylresorcylic acid by a Myxococcus xanthus type III polyketide synthase.
abstract: Fatty acyl-AMP ligases (FAALs) activate fatty acids as acyladenylates, and subsequently catalyze their transfer onto the acyl carrier proteins (ACPs) of polyketide synthases (PKSs) or nonribosomal peptide synthetases to produce lipidic metabolites. Myxococcus xanthus contains a polyketide biosynthesis gene cluster in which putative FAAL (FtpD) and ACP (FtpC) genes are located close to a type III PKS (FtpA) gene. Here we describe the characterization of these three proteins in vitro. FtpD adenylated stearic acid and produced stearoyl-FtpC. The stearoyl moiety was then transferred to FtpA. When extender substrates (malonyl-CoA and methylmalonyl-CoA) were added to the reaction, the alkylresorcinol 5-heptadecyl-4-methyl-benzene-1,3-diol was synthesized. Further in vitro analysis indicated that FtpA produces an alkylresorcylic acid as the direct product, and that this decarboxylates to alkylresorcinol nonenzymatically. This is the first report of a FAAL supplying a long-chain fatty acyl-ACP starter substrate to a type III PKS.
authors.affiliation: Department of Biotechnology, Graduate School of Agriculture and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Tokyo 113-8567, Japan.
authors.forename: Takayuki
authors.initials: T
authors.lastname: Hayashi
authors.forename: Yuta
authors.initials: Y
authors.lastname: Kitamura
authors.forename: Nobutaka
authors.initials: N
authors.lastname: Funa
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Ohnishi
authors.forename: Sueharu
authors.initials: S
authors.lastname: Horinouchi
mesh_terms: D001554:Benzene / Q000737:chemistry / Q000378:metabolism; D055162:Biocatalysis; D019730:Carbon-Sulfur Ligases / Q000235:genetics / Q000378:metabolism*; D019295:Computational Biology; D004274:DNA, Recombinant / Q000235:genetics; D005227:Fatty Acids / Q000096:biosynthesis*; D005810:Multigene Family; D016941:Myxococcus xanthus / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D048630:Polyketide Synthases / Q000378:metabolism*; D012118:Resorcinols / Q000378:metabolism; D048170:Streptomyces lividans / Q000235:genetics
chemical_list: D004274:DNA, Recombinant; D005227:Fatty Acids; D012118:Resorcinols; D048630:Polyketide Synthases; D019730:Carbon-Sulfur Ligases; C018749:long-chain-fatty-acid-(acyl-carrier-protein) ligase; D001554:Benzene; C031389:resorcinol