title: The O-Carbamoyl-Transferase Alb15 Is Responsible for the Modification of Albicidin.
abstract: Albicidin is a potent antibiotic and phytotoxin produced by Xanthomonas albilineans which targets the plant and bacterial DNA gyrase. We now report on a new albicidin derivative which is carbamoylated at the N-terminal coumaric acid by the action of the ATP-dependent O-carbamoyltransferase Alb15, present in the albicidin (alb) gene cluster. Carbamoyl-albicidin was characterized by tandem mass spectrometry from cultures of a Xanthomonas overproducer strain and the gene function confirmed by gene inactivation of alb15 in X. albilineans. Expression of alb15 in Escherichia coli and in vitro reconstitution of the carbamoyltransferase activity confirmed albicidin as the substrate. The chemical synthesis of carbamoyl-albicidin finally enabled us to assess its bioactivity by means of in vitro gyrase inhibition and antibacterial assays. Compared to albicidin, carbamoyl-albicidin showed a significantly higher inhibitory efficiency against bacterial gyrase (∼8 vs 49 nM), which identifies the carbamoyl group as an important structural feature of albicidin maturation.
authors.affiliation: Institut für Chemie, Technische Universität Berlin , Straße des 17. Juni 124, 10623 Berlin, Germany.
authors.forename: Daniel
authors.initials: D
authors.lastname: Petras
authors.affiliation: Institut für Chemie, Technische Universität Berlin , Straße des 17. Juni 124, 10623 Berlin, Germany.
authors.forename: Dennis
authors.initials: D
authors.lastname: Kerwat
authors.affiliation: Institut für Chemie, Technische Universität Berlin , Straße des 17. Juni 124, 10623 Berlin, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Pesic
authors.affiliation: Institut für Chemie, Technische Universität Berlin , Straße des 17. Juni 124, 10623 Berlin, Germany.
authors.forename: Benjamin-F
authors.initials: BF
authors.lastname: Hempel
authors.affiliation: Institut für Chemie, Technische Universität Berlin , Straße des 17. Juni 124, 10623 Berlin, Germany.
authors.forename: Leonard
authors.initials: L
authors.lastname: von Eckardstein
authors.affiliation: Institut für Chemie, Technische Universität Berlin , Straße des 17. Juni 124, 10623 Berlin, Germany.
authors.forename: Siamak
authors.initials: S
authors.lastname: Semsary
authors.affiliation: Cirad , UMR BGPI, F-34398 Montpellier Cedex 5, France.
authors.forename: Julie
authors.initials: J
authors.lastname: Arasté
authors.affiliation: Cirad , UMR BGPI, F-34398 Montpellier Cedex 5, France.
authors.forename: Mélanie
authors.initials: M
authors.lastname: Marguerettaz
authors.affiliation: Cirad , UMR BGPI, F-34398 Montpellier Cedex 5, France.
authors.forename: Monique
authors.initials: M
authors.lastname: Royer
authors.affiliation: Cirad , UMR BGPI, F-34398 Montpellier Cedex 5, France.
authors.forename: Stéphane
authors.initials: S
authors.lastname: Cociancich
authors.affiliation: Institut für Chemie, Technische Universität Berlin , Straße des 17. Juni 124, 10623 Berlin, Germany.
authors.forename: Roderich D
authors.initials: RD
authors.lastname: Süssmuth
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D019878:Carboxyl and Carbamoyl Transferases / Q000235:genetics / Q000378:metabolism*; D005798:Genes, Bacterial; D005810:Multigene Family; D009930:Organic Chemicals / Q000737:chemistry / Q000378:metabolism; D013379:Substrate Specificity; D014974:Xanthomonas / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D009930:Organic Chemicals; C046156:albicidin; C025156:3'-hydroxymethylcephem O-carbamoyltransferase; D019878:Carboxyl and Carbamoyl Transferases