Prominent Roles of the NorR and Fur Regulators in the Escherichia coli Transcriptional Response to Reactive Nitrogen Species

• Published in: Proceedings of the National Academy of Sciences - PNAS 2004-01, Vol.101 (3), p.745-750
• Main Authors: Mukhopadhyay, Partha, Zheng, Ming, Bedzyk, Laura A., LaRossa, Robert A., Storz, Gisela
• Format: Article
• Language: English
• Subjects: Bacteria; Bacterial Proteins - metabolism; Biochemistry; Biological Sciences; Cell growth; Escherichia coli; Escherichia coli - drug effects; Escherichia coli - genetics; Escherichia coli - metabolism; Escherichia coli Proteins - metabolism; FurR protein; Gene Expression Profiling; Gene expression regulation; Gene Expression Regulation, Bacterial - drug effects; Genes; Genes, Bacterial; Genes, Regulator; Messenger RNA; Nitric Oxide Donors - pharmacology; Nitrogen; NorR protein; Oligonucleotide Array Sequence Analysis; Oxidation-Reduction; reactive nitrogen species; Reactive Nitrogen Species - metabolism; Regulator genes; Repressor Proteins - metabolism; RNA; sodium nitrite; Species; Transcription factors; Transcription Factors - genetics; Transcription Factors - metabolism; Transcription, Genetic - drug effects; Transcriptional regulatory elements
• ISSN: 0027-8424; 1091-6490
• DOI: 10.1073/pnas.0307741100

We examined the genomewide transcriptional responses of Escherichia coli treated with nitrosylated glutathione or the nitric oxide (NO)-generator acidified sodium nitrite (NaNO2) during aerobic growth. These assays showed that NorR, a homolog of NO-responsive transcription factors in Ralstonia eutrophus, and Fur, the global repressor of ferric ion uptake, are major regulators of the response to reactive nitrogen species. In contrast, SoxR and OxyR, regulators of the E. coli defenses against superoxide-generating compounds and hydrogen peroxide, respectively, have minor roles. Moreover, additional regulators of the E. coli response to reactive nitrogen species remain to be identified because several of the induced genes were regulated normally in norR, fur, soxRS, and oxyR mutant strains. We propose that the E. coli transcriptional response to reactive nitrogen species is a composite response mediated by the modification of multiple transcription factors containing iron or redox-active cysteines, some specifically designed to sense NO and its derivatives and others that are collaterally activated by the reactive nitrogen species.