OmpR binds to its own promoter Although the evidence suggests that OmpR can regulate its own expression , OmpR autoregulation could be indirect , with OmpR controlling the expression of a second gene , the product of which directly controls the ompR promoter .
The results presented here reveal that H-NS represses ompR , and that OmpR protein directly autoregulates its own expression in response to acid shock by overcoming H-NS repression .
Consequently , DNA mobility-shift assays were performed to determine whether OmpR actually binds to the ompR promoter region .
The results clearly demonstrate that phosphorylated OmpR protein binds to the ompR promoter region with a greater affinity than that of unphosphorylated OmpR .
OmpR footprint In vitro DNA footprinting experiments were then conducted to determine which of the three potential OmpR binding sites in the ompR promoter are actually bound by OmpR .
the ompR promoter region serve as internal controls for spurious binding of OmpR
the ompR promoter region serve as internal controls for spurious binding of OmpR
the ompR promoter region serve as internal controls for spurious binding of OmpR
the ompR promoter region serve as internal controls for spurious binding of OmpR
OmpR binds to its own promoter Although the evidence suggests that OmpR can regulate its own expression , OmpR autoregulation could be indirect , with OmpR controlling the expression of a second gene , the product of which directly controls the ompR promoter .
The results presented here reveal that H-NS represses ompR , and that OmpR protein directly autoregulates its own expression in response to acid shock by overcoming H-NS repression .
Consequently , DNA mobility-shift assays were performed to determine whether OmpR actually binds to the ompR promoter region .
The results clearly demonstrate that phosphorylated OmpR protein binds to the ompR promoter region with a greater affinity than that of unphosphorylated OmpR .
OmpR footprint In vitro DNA footprinting experiments were then conducted to determine which of the three potential OmpR binding sites in the ompR promoter are actually bound by OmpR .
the ompR promoter region serve as internal controls for spurious binding of OmpR
the ompR promoter region serve as internal controls for spurious binding of OmpR
the ompR promoter region serve as internal controls for spurious binding of OmpR
the ompR promoter region serve as internal controls for spurious binding of OmpR
Lee et al. established that loss of virulence in ompR mutants could be partly attributed to the loss of the transcriptional regulator of the SsrA-SsrB system-the OmpR protein .
Genes previously characterised as OmpR-regulated with decreased levels of expression in S. Typhi Ty2 ompR mutants were tviABCDE , vexABCDE , ompC and ompS .
Since previous studies have demonstrated that OmpR is a regulator of Agf expression , we decided to determine whether the TnphoA insertion in 2 final candidate mutants is in the ompR gene .
ompR are required for resistance to the bile salt sodium deoxycholate in S. Typhi We have shown that LtrR has a role in the synthesis of the major outer membrane proteins OmpF and OmpC through its direct regulation of OmpR .
The ompR mutant was also complemented with the ompR coding region from Escheri-chia coli under the control of pQE60ompR ; this construct was used since it is identical to the S. Typhi OmpR protein .
The ompR mutant was also complemented with the ompR coding region from Escheri-chia coli under the control of an IPTG-inducible promoter ; this construct was used since it is identical to the S. Typhi OmpR protein .
CadC interacts directly with OmpR Since S. enterica serovar Typhimurium OmpR response re-gulator was shown to induce its own synthesis by binding to its promoter , we hypothesized that CadC could mediate the repression of ompR gene expression by direct interaction with OmpR , sterically hindering binding of OmpR to RNA polymerase .
CadC interacts directly with OmpR Since S. enterica serovar Typhimurium OmpR response re-gulator was shown to induce its own synthesis by binding to its promoter , we hypothesized that CadC could mediate the repression of ompR gene expression by direct interaction with OmpR , sterically hindering binding of OmpR to its own promoter .
Thus , OmpR only directly regulates two , i.e. , ompR , of the four genes .