biostudies-literatureNakano MMNIAID NIH HHSNational Institutes of HealthNIGMS NIH HHSNational Science Foundation815-27https://www.ebi.ac.uk/biostudies/studies/S-EPMC4258114biostudies-literatureUnknown94(4)Spx, a member of the ArsC (arsenate reductase) protein family, is conserved in Gram-positive bacteria, and interacts with RNA polymerase to activate transcription in response to toxic oxidants. In Bacillus anthracis str. Sterne, resistance to oxidative stress requires the activity of two paralogues, SpxA1 and SpxA2. Suppressor mutations were identified in spxA1 mutant cells that conferred resistance to hydrogen peroxide. The mutations generated null alleles of the saiR gene and resulted in elevated spxA2 transcription. The saiR gene resides in the spxA2 operon and encodes a member of the Rrf2 family of transcriptional repressors. Derepression of spxA2 in a saiR mutant required SpxA2, indicating an autoregulatory mechanism of spxA2 control. Reconstruction of SaiR-dependent control of spxA2 Molecular microbiologyspxA2, encoding a regulator of stress resistance in Bacillus anthracis, is controlled by SaiR, a new member of the Rrf2 protein family.PMC4258114AI092313T32 AI0074725T32AI007472R21 AI092313MCB1157424GM045898R01 GM045898Kominos-Marvell WNader YMZuber PBarendt SMNakano MMSane BJones MBfalsespxA2, encoding a regulator of stress resistance in Bacillus anthracis, is controlled by SaiR, a new member of the Rrf2 protein family.Spx, a member of the ArsC (arsenate reductase) protein family, is conserved in Gram-positive bacteria, and interacts with RNA polymerase to activate transcription in response to toxic oxidants. In Bacillus anthracis str. Sterne, resistance to oxidative stress requires the activity of two paralogues, SpxA1 and SpxA2. Suppressor mutations were identified in spxA1 mutant cells that conferred resistance to hydrogen peroxide. The mutations generated null alleles of the saiR gene and resulted in elevated spxA2 transcription. The saiR gene resides in the spxA2 operon and encodes a member of the Rrf2 family of transcriptional repressors. Derepression of spxA2 in a saiR mutant required SpxA2, indicating an autoregulatory mechanism of spxA2 control. Reconstruction of SaiR-dependent control of spxA2 2014-01-01T00:00:00Z2014 Nov2026-05-02T09:48:56.666Z2019-03-27T01:41:13ZS-EPMC42581142523123510.1111/mmi.12798