title: Structure of the bacterial plant-ferredoxin receptor FusA.
abstract: Iron is a limiting nutrient in bacterial infection putting it at the centre of an evolutionary arms race between host and pathogen. Gram-negative bacteria utilize TonB-dependent outer membrane receptors to obtain iron during infection. These receptors acquire iron either in concert with soluble iron-scavenging siderophores or through direct interaction and extraction from host proteins. Characterization of these receptors provides invaluable insight into pathogenesis. However, only a subset of virulence-related TonB-dependent receptors have been currently described. Here we report the discovery of FusA, a new class of TonB-dependent receptor, which is utilized by phytopathogenic Pectobacterium spp. to obtain iron from plant ferredoxin. Through the crystal structure of FusA we show that binding of ferredoxin occurs through specialized extracellular loops that form extensive interactions with ferredoxin. The function of FusA and the presence of homologues in clinically important pathogens suggests that small iron-containing proteins represent an iron source for bacterial pathogens.
authors: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.|Institute of Microbiology and Infection, School of Immunity and Infection, University of Birmingham, Birmingham B15 2TT, UK.|Infection and Immunity Program, Biomedicine Discovery Institute and Department of Microbiology, Monash University, Clayton, Victoria 3804, Australia.
authors: Rhys
authors: 0000-0002-8195-5348
authors: R
authors: Grinter
authors: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
authors: Inokentijs
authors: I
authors: Josts
authors: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
authors: Khedidja
authors: K
authors: Mosbahi
authors: Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
authors: Aleksander W
authors: AW
authors: Roszak
authors: Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
authors: Richard J
authors: RJ
authors: Cogdell
authors: Bijvoet Center for Biomolecular Research, Faculty of Science, Utrecht University, Utrecht 3584 CH, The Netherlands.
authors: Alexandre M J J
authors: AM
authors: Bonvin
authors: School of Life Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
authors: Joel J
authors: JJ
authors: Milner
authors: Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
authors: Sharon M
authors: SM
authors: Kelly
authors: School of Life Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
authors: Olwyn
authors: O
authors: Byron
authors: Institute of Molecular, Cell and Systems Biology, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
authors: Brian O
authors: 0000-0003-3363-4168
authors: BO
authors: Smith
authors: Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK.
authors: Daniel
authors: D
authors: Walker
mesh_terms: D001425:Bacterial Outer Membrane Proteins / Q000737:chemistry*; D001426:Bacterial Proteins / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004926:Escherichia coli / Q000378:metabolism; D005288:Ferredoxins / Q000737:chemistry*; D015964:Gene Expression Regulation, Bacterial; D007501:Iron / Q000737:chemistry*; D007506:Iron-Sulfur Proteins / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008565:Membrane Proteins / Q000737:chemistry*; D016366:Open Reading Frames; D044043:Pectobacterium / Q000737:chemistry*; D020653:Peptide Elongation Factor G / Q000737:chemistry*; D010802:Phylogeny; D011485:Protein Binding; D000072417:Protein Domains
chemical_list: D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D005288:Ferredoxins; D007506:Iron-Sulfur Proteins; D008565:Membrane Proteins; D020653:Peptide Elongation Factor G; C057616:tonB protein, Bacteria; D007501:Iron