Prominent roles of the NorR and Fur regulators in the Escherichia coli transcriptional response to reactive nitrogen species.
We examined the genomewide transcriptional responses of Escherichia coli treated with nitrosylated glutathione or the nitric oxide (NO)-generator acidified sodium nitrite (NaNO(2)) 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.
Mukhopadhyay
Partha
P
Cell Biology and Metabolism Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA.
Zheng
Ming
M
Bedzyk
Laura A
LA
LaRossa
Robert A
RA
Storz
Gisela
G
D001426:Bacterial Proteins / Q000378:metabolism*; D004926:Escherichia coli / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D029968:Escherichia coli Proteins / Q000378:metabolism*; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial / Q000187:drug effects; D005798:Genes, Bacterial; D005809:Genes, Regulator; D020030:Nitric Oxide Donors / Q000494:pharmacology; D020411:Oligonucleotide Array Sequence Analysis; D010084:Oxidation-Reduction; D026361:Reactive Nitrogen Species / Q000378:metabolism*; D012097:Repressor Proteins / Q000378:metabolism*; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic / Q000187:drug effects
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D020030:Nitric Oxide Donors; D026361:Reactive Nitrogen Species; D012097:Repressor Proteins; D014157:Transcription Factors; C068477:ferric uptake regulating proteins, bacterial