title: Unprecedented anthranilate priming involving two enzymes of the acyl adenylating superfamily in aurachin biosynthesis.
abstract: Biosynthesis of many polyketide-derived secondary metabolites is initiated by incorporating starter units other than acetate. Thus, understanding their priming mechanism is of importance for metabolic engineering. Insight into the loading process of anthranilate into the biosynthetic pathway for the quinoline alkaloids aurachins has been provided by the sequencing of a partial biosynthetic gene cluster in the myxobacterium Stigmatella aurantiaca. The cluster encodes a predicted aryl:CoA ligase AuaE that was hypothesized to activate and transfer anthranilate to the acyl carrier protein AuaB. However, gene inactivation and in vitro experiments described here contradicted this model. Aided by the genome sequence of S. aurantiaca, we identified an additional aryl:CoA ligase homologue, AuaEII, encoded in a different gene operon, which is additionally required for anthranilate priming. We report the characterization of both enzymes and the elucidation of a novel non-acetate priming strategy in thio-templated biosynthetic machineries.
authors.affiliation: Helmholtz-Institut für Pharmazeutische Forschung Saarland, Helmholtz Zentrum für Infektionsforschung Braunschweig and Pharmazeutische Biotechnologie, Universität des Saarlandes, Postfach 151150, 66041 Saarbrücken, Germany.
authors.forename: Dominik
authors.initials: D
authors.lastname: Pistorius
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Li
authors.forename: Stéphane
authors.initials: S
authors.lastname: Mann
authors.forename: Rolf
authors.initials: R
authors.lastname: Müller
mesh_terms: D000213:Acyl Carrier Protein / Q000235:genetics / Q000378:metabolism; D000595:Amino Acid Sequence; D003066:Coenzyme A Ligases / Q000235:genetics* / Q000378:metabolism; D005798:Genes, Bacterial; D008969:Molecular Sequence Data; D009876:Operon; D011804:Quinolines / Q000378:metabolism*; D015363:Quinolones / Q000378:metabolism*; D016415:Sequence Alignment; D020606:Stigmatella aurantiaca / Q000201:enzymology* / Q000235:genetics* / Q000378:metabolism; D062367:ortho-Aminobenzoates / Q000378:metabolism*
chemical_list: D000213:Acyl Carrier Protein; D011804:Quinolines; D015363:Quinolones; D062367:ortho-Aminobenzoates; C031385:anthranilic acid; D003066:Coenzyme A Ligases