title: Nonribosomal peptide synthetase with a unique iterative-alternative-optional mechanism catalyzes amonabactin synthesis in Aeromonas.
abstract: Based on the exploration of data generated by genome sequencing, a bioinformatics approach has been chosen to identify the biosynthetic pathway of the siderophores produced by Aeromonas species. The amonabactins, considered as a virulence factor, represent a family of four variants of catechol peptidic siderophores containing Dhb, Lys, Gly, and an aromatic residue either Trp or Phe in a D-configuration. The synthesis operon is constituted of seven genes named amoCEBFAGH and is iron-regulated. The cluster includes genes encoding proteins involved in the synthesis and incorporation of the Dhb monomer, and genes encoding specific nonribosomal peptide synthetases, which are responsible for the building of the peptidic moiety. The amonabactin assembly line displays a still so far not described atypical mode of synthesis that is iterative, alternative, and optional. A disruption mutant in the adenylation domain of AmoG was unable to synthesize any amonabactin and to grow in iron stress conditions while a deletion of amoH resulted in the production of only two over the four forms. The amo cluster is widespread among most of the Aeromonas species, only few species produces the enterobactin siderophore.
authors.affiliation: EA 7394-ICV-Institut Charles Viollette, Univ. Lille, INRA, ISA, Univ. Artois, Univ. Littoral Côte d'Opale, F-59000, Lille, France. al_hamadi_82@yahoo.com.
authors.forename: Qassim
authors.initials: Q
authors.lastname: Esmaeel
authors.affiliation: EA 7394-ICV-Institut Charles Viollette, Univ. Lille, INRA, ISA, Univ. Artois, Univ. Littoral Côte d'Opale, F-59000, Lille, France.
authors.forename: Mickael
authors.initials: M
authors.lastname: Chevalier
authors.affiliation: EA 7394-ICV-Institut Charles Viollette, Univ. Lille, INRA, ISA, Univ. Artois, Univ. Littoral Côte d'Opale, F-59000, Lille, France.
authors.forename: Gabrielle
authors.initials: G
authors.lastname: Chataigné
authors.affiliation: EA 7394-ICV-Institut Charles Viollette, Univ. Lille, INRA, ISA, Univ. Artois, Univ. Littoral Côte d'Opale, F-59000, Lille, France.
authors.forename: Rathinasamy
authors.initials: R
authors.lastname: Subashkumar
authors.affiliation: EA 7394-ICV-Institut Charles Viollette, Univ. Lille, INRA, ISA, Univ. Artois, Univ. Littoral Côte d'Opale, F-59000, Lille, France.|TERRA Research Centre, Microbial Processes and Interactions, Gembloux Agro-Bio Tech, University of Liege, B-5030, Gembloux, Belgium.
authors.forename: Philippe
authors.initials: P
authors.lastname: Jacques
authors.affiliation: EA 7394-ICV-Institut Charles Viollette, Univ. Lille, INRA, ISA, Univ. Artois, Univ. Littoral Côte d'Opale, F-59000, Lille, France.|Inria-Lille Nord Europe, Univ Lille, CNRS, Centrale Lille, UMR9189 - CRIStAL- Centre de Recherche en Informatique Signal et Automatique de Lille, F-59000, Lille, France.
authors.forename: Valérie
authors.initials: V
authors.lastname: Leclère
mesh_terms: D000333:Aeromonas / Q000201:enzymology* / Q000235:genetics; D055786:Gene Knockout Techniques; D005810:Multigene Family; D009842:Oligopeptides / Q000096:biosynthesis*; D009876:Operon; D010453:Peptide Synthases / Q000235:genetics / Q000378:metabolism*; D017262:Siderophores / Q000096:biosynthesis*
chemical_list: D009842:Oligopeptides; D017262:Siderophores; D010453:Peptide Synthases; C104385:non-ribosomal peptide synthase
keywords: Aeromonas; Amonabactin; NRPS; Nonribosomal peptide synthetase; Siderophore