The oxyR from Agrobacterium tumefaciens: evaluation of its role in the regulation of catalase and peroxide responses

The Catalase-Peroxidase KatG Is Required for Virulence of Xanthomonas campestris pv. campestris in a Host Plant by Providing Protection against Low Levels of H 2 O 2

“…2B). This indicates that OxyR regulates the peroxide-inducible expression of katG and that the gene is a member of the OxyR regulon, as in several bacteria (6,16,20).…”

“…phaseoli highly match (10 of 16) the E. coli consensus sequence (5,14). Nonetheless, in several microorganisms, the OxyR binding sequences of the target promoters are diverse and differ from the consensus sequence (20,30).…”

The katA Catalase Gene Is Regulated by OxyR in both Free-Living and Symbiotic Sinorhizobium meliloti

“…This noninduction of oxyR expression after H 2 O 2 exposure indicates that oxyR is constitutively expressed, independently of exogenous H 2 O 2 . Nevertheless, a reduction in ␤-glucuronidase activity was observed in RmoxyR complemented by plasmid pBBR-oxyR compared to that in the RmoxyR mutant, indicating that oxyR downregulates its own expression as in all bacterial species studied so far (27).…”

“…An oxyR gene has been identified in 31 bacterial genomes (6,27). The position of oxyR is very variable in the different bacterial genomes, but it is often next to a gene involved in oxidative stress protection and regulated by OxyR: for example, ahpC in Mycobacterium tuberculosis (7) and Xanthomonas campestris pv.…”

Physiological and Expression Analyses of Agrobacterium tumefaciens trxA , Encoding Thioredoxin

“…The observed patterns of oxidants inducing A. tumefaciens trxA expression have similarity to patterns of A. tumefaciens OxyR (a H 2 O 2 sensor/ transcription regulator)-regulated genes (21). In addition, SoxR (7) and OhrR (6) are members of oxidative stress-responsive transcription regulators that sense increased levels of superoxide anions and organic hydroperoxides, respectively.…”