Redox sensing by prokaryotic transcription factors.
Prokaryotic cells employ redox-sensing transcription factors to detect elevated levels of reactive oxygen species and regulate expression of antioxidant genes. In Escherichia coli, two such transcription factors, OxyR and SoxR, have been well characterized. The OxyR protein contains a thiol-disulfide redox switch to sense hydrogen peroxide. The SoxR protein uses a 2Fe-2S cluster to sense superoxide generated by redox-cycling agents, as well as to sense nitric oxide. Both proteins are turned on and off with very fast kinetics (approximate minutes), allowing rapid cellular responses to oxidative stress. The mechanisms by which these and other prokaryotic proteins sense redox signals have provided useful paradigms for understanding redox signal transduction in eukaryotic cells.
Zheng
M
M
Cell Biology and Metabolism Branch, National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD 20892, USA. ming@chemvax.princeton.edu
Storz
G
G
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000378:metabolism*; D004268:DNA-Binding Proteins; D004926:Escherichia coli / Q000378:metabolism*; D029968:Escherichia coli Proteins; D006861:Hydrogen Peroxide / Q000378:metabolism; D007506:Iron-Sulfur Proteins / Q000378:metabolism; D008969:Molecular Sequence Data; D010084:Oxidation-Reduction; D018384:Oxidative Stress; D012097:Repressor Proteins / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D013481:Superoxides / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism*
D001426:Bacterial Proteins; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; D007506:Iron-Sulfur Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; C499299:oxyR protein, E coli; D013481:Superoxides; C070724:SoxR protein, Bacteria; D006861:Hydrogen Peroxide