title: Helicobacter pylori thioredoxin is an arginase chaperone and guardian against oxidative and nitrosative stresses.
abstract: The gastric human pathogen Helicobacter pylori faces formidable challenges in the stomach including reactive oxygen and nitrogen intermediates. Here we demonstrate that arginase activity, which inhibits host nitric oxide production, is post-translationally stimulated by H. pylori thioredoxin (Trx) 1 but not the homologous Trx2. Trx1 has chaperone activity that renatures urea- or heat-denatured arginase back to the catalytically active state. Most reactive oxygen and nitrogen intermediates inhibit arginase activity; this damage is reversed by Trx1, but not Trx2. Trx1 and arginase equip H. pylori with a "renox guardian" to overcome abundant nitrosative and oxidative stresses encountered during the persistence of the bacterium in the hostile gastric environment.
authors.affiliation: Department of Microbiology & Immunology and Biological Sciences, University of South Alabama, Mobile, AL, USA. dmcgjee@lsuhsc.edu
authors.forename: David J
authors.initials: DJ
authors.lastname: McGee
authors.forename: Sateesh
authors.initials: S
authors.lastname: Kumar
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Viator
authors.forename: Jeffrey R
authors.initials: JR
authors.lastname: Bolland
authors.forename: Julio
authors.initials: J
authors.lastname: Ruiz
authors.forename: Domenico
authors.initials: D
authors.lastname: Spadafora
authors.forename: Traci L
authors.initials: TL
authors.lastname: Testerman
authors.forename: David J
authors.initials: DJ
authors.lastname: Kelly
authors.forename: Lewis K
authors.initials: LK
authors.lastname: Pannell
authors.forename: Henry J
authors.initials: HJ
authors.lastname: Windle
mesh_terms: D001119:Arginase / Q000737:chemistry*; D018834:Chaperonin 60 / Q000737:chemistry; D002846:Chromatography, Affinity; D003001:Cloning, Molecular; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism; D016480:Helicobacter pylori / Q000378:metabolism*; D006801:Humans; D013058:Mass Spectrometry; D008565:Membrane Proteins / Q000378:metabolism; D018832:Molecular Chaperones / Q000378:metabolism; D009154:Mutation; D009584:Nitrogen / Q000737:chemistry* / Q000378:metabolism; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D010455:Peptides / Q000737:chemistry; D010957:Plasmids / Q000378:metabolism; D017382:Reactive Oxygen Species; D013050:Spectrometry, Fluorescence; D013270:Stomach / Q000382:microbiology; D013879:Thioredoxins / Q000378:metabolism*; D014461:Ultracentrifugation; D014510:Urease / Q000737:chemistry
chemical_list: D018834:Chaperonin 60; D008565:Membrane Proteins; D018832:Molecular Chaperones; D010455:Peptides; D017382:Reactive Oxygen Species; D013879:Thioredoxins; D014510:Urease; D001119:Arginase; D009584:Nitrogen