title: Cellular organization of siderophore biosynthesis in Pseudomonas aeruginosa: Evidence for siderosomes.
abstract: Pyoverdine I (PVDI) and pyochelin (PCH) are the two major siderophores produced by Pseudomonas aeruginosa PAO1 to import iron. The biochemistry of the biosynthesis of these two siderophores has been described in detail in the literature over recent years. PVDI assembly requires the coordinated action of seven cytoplasmic enzymes and is followed by a periplasmic maturation before secretion of the siderophore into the extracellular medium by the efflux system PvdRT-OpmQ. PCH biosynthesis also involves seven cytoplasmic enzymes but no periplasmic maturation. Recent findings indicate that the cytoplasmic enzymes involved in each of these two siderophore biosynthesis pathways can form siderophore-specific multi-enzymatic complexes called siderosomes associated with the inner leaflet of the cytoplasmic membrane. This organization may optimize the transfer of the siderophore precursors between the various participating enzymes and avoid the diffusion of siderophore precursors, able to chelate metals, throughout the cytoplasm. Here, we describe these recently published findings and discuss the existence of these siderosomes in P. aeruginosa.
authors.affiliation: UMR 7242, Université de Strasbourg-CNRS, ESBS, Blvd Sébastien Brant, Illkirch, Strasbourg F-67413, France.
authors.forename: Véronique
authors.initials: V
authors.lastname: Gasser
authors.affiliation: UMR 7242, Université de Strasbourg-CNRS, ESBS, Blvd Sébastien Brant, Illkirch, Strasbourg F-67413, France.
authors.forename: Laurent
authors.initials: L
authors.lastname: Guillon
authors.affiliation: UMR 7242, Université de Strasbourg-CNRS, ESBS, Blvd Sébastien Brant, Illkirch, Strasbourg F-67413, France.
authors.forename: Olivier
authors.initials: O
authors.lastname: Cunrath
authors.affiliation: UMR 7242, Université de Strasbourg-CNRS, ESBS, Blvd Sébastien Brant, Illkirch, Strasbourg F-67413, France. Electronic address: isabelle.schalk@unistra.fr.
authors.forename: Isabelle J
authors.initials: IJ
authors.lastname: Schalk
mesh_terms: D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D053898:Biosynthetic Pathways; D003593:Cytoplasm / Q000201:enzymology / Q000378:metabolism; D015151:Immunoblotting; D008164:Luminescent Proteins / Q000235:genetics / Q000378:metabolism; D008856:Microscopy, Fluorescence; D015394:Molecular Structure; D009842:Oligopeptides / Q000096:biosynthesis* / Q000737:chemistry; D011550:Pseudomonas aeruginosa / Q000235:genetics / Q000378:metabolism*; D017262:Siderophores / Q000096:biosynthesis* / Q000737:chemistry
chemical_list: D001426:Bacterial Proteins; D008164:Luminescent Proteins; D009842:Oligopeptides; D017262:Siderophores; C042453:pyoverdin
keywords: Iron uptake; Nonribosomal peptide synthetase; Pseudomonas aeruginosa; Siderophore; Siderosome