Subcellular localization of the pyoverdine biogenesis machinery of Pseudomonas aeruginosa: A membrane-associated "siderosome"

The peptidic siderophore pyoverdine is the primary iron uptake system of fluorescent pseudomonads, and a virulence factor in the opportunistic pathogen Pseudomonas aeruginosa. Pyoverdine biogenesis is a co-ordinate process requiring several precursor-generating enzymes and large nonribosomal peptide synthetases (NRPSs) in the cytoplasm, followed by extracytoplasmic maturation. By using cell fractionation, protein-protein interaction, and in vivo labeling assays we obtained evidence that, in P. aeruginosa, pyoverdine NRPSs assemble with precursor-generating enzymes into a membrane-bound multi-enzymatic complex, for which we propose the name "siderosome". The pyoverdine biogenetic complex represents a novel example of subcellular compartmentalization of a secondary metabolic pathway in prokaryotes. Structured summary of protein interactions: PvdA and PvdD colocalize by confocal microscopy (View interaction) PvdA and PvdJ colocalize by confocal microscopy (View interaction) PvdA physically interacts with PvdJ by two hybrid (View interaction) PvdA physically interacts with PvdJ and PvdL by pull down (View interaction) (C) 2013 Federation of European Biochemical Societies. Published by Elsevier B. V. All rights reserved.