title: Effects of penetrating and non-penetrating oxidants on Escherichia coli.
abstract: Treatment of Escherichia coli K-12 cells aerobically grown in M9 glucose salt medium (H2O2) and non-penetrating (ferricyanide) oxidants resulted in similar inhibition of growth and decrease in intracellular K+ pool by 15%. Only H2O2 inhibited growth of auxotrophic strains grown in M9 medium supplemented with protein hydrolysate. Ferricyanide reduction was associated with decrease in low-molecular-weight thiols, whereas the treatment of cells with H2O2 increased their level. Pretreatment of cells with ferricyanide enhanced the H2O2-induced expression of katG gene encoding for catalase HPI; this gene is a member of the gene family controlled by the oxyR gene. Pretreatment with ferricyanide inhibited H2O2-induced expression of the sfiA gene which is the member of the gene family controlled by the recA and lexA genes. Glutathione is the major low-molecular-weight thiol in E. coli, and it can play different roles in cellular responses to H2O2 and ferricyanide.
authors.affiliation: Institute of Ecology and Genetics of Microorganisms, Ural Branch of the Russian Academy of Sciences, Perm, Russia.
authors.forename: G V
authors.initials: GV
authors.lastname: Smirnova
authors.forename: N G
authors.initials: NG
authors.lastname: Muzyka
authors.forename: M N
authors.initials: MN
authors.lastname: Glukhovchenko
authors.forename: O N
authors.initials: ON
authors.lastname: Oktyabrsky
mesh_terms: D000975:Antioxidants / Q000378:metabolism; D001426:Bacterial Proteins / Q000235:genetics; D002374:Catalase / Q000378:metabolism; D004926:Escherichia coli / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000378:metabolism; D029968:Escherichia coli Proteins; D005295:Ferrocyanides / Q000494:pharmacology*; D005798:Genes, Bacterial; D005978:Glutathione / Q000378:metabolism; D006861:Hydrogen Peroxide / Q000494:pharmacology*; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D018384:Oxidative Stress; D010544:Peroxidases / Q000235:genetics
chemical_list: D000975:Antioxidants; D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D005295:Ferrocyanides; C053139:sulA protein, E coli; D006861:Hydrogen Peroxide; D010544:Peroxidases; D002374:Catalase; C076136:catalase HPI; D009247:NADH, NADPH Oxidoreductases; C014227:ferricyanide reductase; C020354:hexacyanoferrate II; D005978:Glutathione