title: Redox proteomics uncovers peroxynitrite-sensitive proteins that help Escherichia coli to overcome nitrosative stress.
abstract: Peroxynitrite is a highly reactive chemical species with antibacterial properties that are synthesized in immune cells. In a proteomic approach, we identified specific target proteins of peroxynitrite-induced modifications in Escherichia coli. Although peroxynitrite caused a fairly indiscriminate nitration of tyrosine residues, reversible modifications of protein thiols were highly specific. We used a quantitative redox proteomic method based on isotope-coded affinity tag chemistry and identified four proteins consistently thiol-modified in cells treated with peroxynitrite as follows: AsnB, FrmA, MaeB, and RidA. All four were required for peroxynitrite stress tolerance in vivo. Three of the identified proteins were modified at highly conserved cysteines, and MaeB and FrmA are known to be directly involved in the oxidative and nitrosative stress response in E. coli. In in vitro studies, we could show that the activity of RidA, a recently discovered enamine/imine deaminase, is regulated in a specific manner by the modification of its single conserved cysteine. Mutation of this cysteine 107 to serine generated a constitutively active protein that was not susceptible to peroxynitrite.
authors.affiliation: Medical Proteome Center, Ruhr University Bochum, Universitätsstrasse 150, 44780 Bochum, Germany.
authors.forename: Claudia
authors.initials: C
authors.lastname: Lindemann
authors.forename: Nataliya
authors.initials: N
authors.lastname: Lupilova
authors.forename: Alexandra
authors.initials: A
authors.lastname: Müller
authors.forename: Bettina
authors.initials: B
authors.lastname: Warscheid
authors.forename: Helmut E
authors.initials: HE
authors.lastname: Meyer
authors.forename: Katja
authors.initials: K
authors.lastname: Kuhlmann
authors.forename: Martin
authors.initials: M
authors.lastname: Eisenacher
authors.forename: Lars I
authors.initials: LI
authors.lastname: Leichert
mesh_terms: D004926:Escherichia coli / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010084:Oxidation-Reduction; D018384:Oxidative Stress / Q000187:drug effects* / Q000235:genetics; D030421:Peroxynitrous Acid / Q000737:chemistry / Q000494:pharmacology*; D040901:Proteomics
chemical_list: D029968:Escherichia coli Proteins; D030421:Peroxynitrous Acid
keywords: Microbiology; Nitrosative Stress; Peroxynitrite; Proteomics; Redox; Thiol