These features of the ugtL promoter are atypical for PhoP-regulated promoters and could be the reason that ugtL transcription also requires the SlyA protein ( Fig. 1A ) .
These features of the ugtL promoter are atypical for PhoP-regulated promoters and could be the reason that ugtL transcription also requires the SlyA protein ( Fig. 1A ) .
The PhoP and SlyA protein appear to be part of a feed-forward loop that controls transcription of the ugtL gene and possibly additional PhoP-regulated genes .
We propose that the PhoP proteins control ugtL transcription .
Then , we found that the PhoP protein binds to two regions of the ugtL promoter : an upstream region overlapping the potential 10 of the ugtL promoter .
Then , we found that the PhoP protein binds to two regions of the ugtL promoter : an upstream region harboring a 1-proximal region with no resemblance to the PhoP box .
Then , we found that the PhoP protein binds to two regions of the ugtL promoter : an upstream region harboring an imperfect hexanucleotide repeat .
These results demonstrate that the PhoP proteins bind to the ugtL promoter .
The PhoP Binding Sites in the ugtL Promoter Are Required for Binding of the PhoP Protein for Transcription of the ugtL Gene in Vivo -- To examine the role of the PhoP binding sites in the ugtL promoter , we generated a set of isogenic strains harboring nucleotide substitutions at either downstream PhoP binding sites in the ugtL promoter .
The PhoP Binding Sites in the ugtL Promoter Are Required for Binding of the PhoP Protein for Transcription of the ugtL Gene in Vivo -- To examine the role of the PhoP binding sites in the ugtL promoter , we generated a set of isogenic strains harboring nucleotide substitutions at either the upstream in the ugtL promoter .
The PhoP Binding Sites in the ugtL Promoter Are Required for Binding of the PhoP Protein for Transcription of the ugtL Gene in Vivo -- To examine the role of the PhoP binding sites in the ugtL promoter , we generated a set of isogenic strains harboring wild-type sequences at either downstream PhoP binding sites in the ugtL promoter .
The PhoP Binding Sites in the ugtL Promoter Are Required for Binding of the PhoP Protein for Transcription of the ugtL Gene in Vivo -- To examine the role of the PhoP binding sites in the ugtL promoter , we generated a set of isogenic strains harboring wild-type sequences at either the upstream in the ugtL promoter .
The PhoP Binding Sites in the ugtL Promoter Are Required for Binding of the PhoP Protein to the ugtL Promoter in Vitro -- To examine the role of the PhoP binding sites in the ugtL promoter , we generated a set of isogenic strains harboring nucleotide substitutions at either downstream PhoP binding sites in the ugtL promoter .
The PhoP Binding Sites in the ugtL Promoter Are Required for Binding of the PhoP Protein to the ugtL Promoter in Vitro -- To examine the role of the PhoP binding sites in the ugtL promoter , we generated a set of isogenic strains harboring nucleotide substitutions at either the upstream in the ugtL promoter .
The PhoP Binding Sites in the ugtL Promoter Are Required for Binding of the PhoP Protein to the ugtL Promoter in Vitro -- To examine the role of the PhoP binding sites in the ugtL promoter , we generated a set of isogenic strains harboring wild-type sequences at either downstream PhoP binding sites in the ugtL promoter .
The PhoP Binding Sites in the ugtL Promoter Are Required for Binding of the PhoP Protein to the ugtL Promoter in Vitro -- To examine the role of the PhoP binding sites in the ugtL promoter , we generated a set of isogenic strains harboring wild-type sequences at either the upstream in the ugtL promoter .
These results demonstrate that binding of the PhoP protein to both PhoP binding sites in the ugtL promoter is required for ugtL transcription .
The PhoP proteins bind to the ugtL promoter .
We have established that transcription of polymyxin B resistance gene ugtL is controlled by the PhoP proteins in what appears to be a feedforward loop design .
Mutation of the PhoP2 sites abolished Fig. 3A , possibly because it prevented binding of the PhoP protein to the ugtL promoter as suggested by the DNase Fig. 3B .
Mutation of the PhoP2 sites abolished Fig. 3A , possibly because it prevented binding of the PhoP protein to the ugtL promoter as suggested by the DNase I footprinting results .
Mutation of the PhoP2 sites abolished ugtL transcription , possibly because it prevented binding of the PhoP protein to the ugtL promoter as suggested by the DNase Fig. 3B .
Mutation of the PhoP2 sites abolished ugtL transcription , possibly because it prevented binding of the PhoP protein to the ugtL promoter as suggested by the DNase I footprinting results .
Mutation of the PhoP1 sites abolished Fig. 3A , possibly because it prevented binding of the PhoP protein to the ugtL promoter as suggested by the DNase Fig. 3B .
Mutation of the PhoP1 sites abolished Fig. 3A , possibly because it prevented binding of the PhoP protein to the ugtL promoter as suggested by the DNase I footprinting results .
Mutation of the PhoP1 sites abolished ugtL transcription , possibly because it prevented binding of the PhoP protein to the ugtL promoter as suggested by the DNase Fig. 3B .
Mutation of the PhoP1 sites abolished ugtL transcription , possibly because it prevented binding of the PhoP protein to the ugtL promoter as suggested by the DNase I footprinting results .
Taken together with the identification of binding sites for both PhoP proteins in Fig. 2C , these results support the notion of a feedforward design in the regulation of ugtL transcription .
Taken together with the identification of binding sites for both PhoP proteins in the ugtL promoter , these results support the notion of a feedforward design in the regulation of ugtL transcription .
Although full resist-ance to polymyxin B requires ugtL , these genes appear to be differentially regulated by PhoP in that transcription of Fig. 1A
Although full resist-ance to polymyxin B requires ugtL , these genes appear to be differentially regulated by PhoP in that transcription of the former
Model _ illustrating the feed-forward regulation of the ugtL gene by the PhoP proteins
PhoP along with SlyA bind to the ugtL promoter
The PhoP-regulated ugtL gene is required for resistance to magainin 2 and other alpha-helical antimicrobial peptides To examine whether the ugtL and STM1600 genes were required for resistance to magainin 2 , we constructed strains completely deleted for the chromosomal copies of these genes ( see Experimental procedures ) .
Having demonstrated previously that ugtL is a PhoP-activated gene ( Hilbert et al. , 1999 ) , these results validated our strategy for the recovery of the PhoP-regulated peptide resistance determinants .
The ugtL gene mediates polymyxin B resistance independently of the PmrA-PmrB system phoP Salmonella are > 20 times more polymyxin sensitive than a pmrA mutant when bacteria are grown in low ygjU 3394555 3392617 rfaB rfaI 3914096 3915562 slsA STM3760 cigR 3959077 3960805 rhaT rhaR 4260472 4262386 STM0725 STM0726 STM0724 792487 790384 Mg2 + ( Wosten et al. , 2000 ) , indicating that a PmrA-inde-pendent PhoP-regulated gene ( s ) is necessary for poly-myxin resistance .
These results demonstrate that PhoP-regulated polymyxin B resistance is mediated by the ugtL gene and by some of the targets of PmrA -- PmrB regulation ( Groisman et al. , 1997 ; Gunn et al. , 1998 ) .
w ild-type + y v q e jA cto + r y v q e jA cto + r pyqj PhoP-regulated magainin 2 resistance is mediated by the ugtL , pagP and yqjA genes Because the ugtL mutant was not as susceptible to magai-nin 2 as the phoP mutant ( Fig. 2A ) , we reasoned that another PhoP-regulated gene ( s ) must be involved in magainin 2 resistance .
w ild-type + y v q e jA cto + r y v q e jA cto + r pyqj PhoP-regulated magainin 2 resistance is mediated by the ugtL , pagP and yqjA genes Because the ugtL mutant was not as susceptible to magai-nin 2 as the phoP mutant ( Fig. 2A ) , we reasoned that another PhoP-regulated gene ( s ) must be involved in magainin 2 resistance .
A ugtL pagP double mutant was more sensitive than either the ugtL or pagP single mutants but still more resistant than the phoP mutant ( Fig. 2C ) , indicating that the ugtL and pagP genes participate in different pathways of magainin 2 resistance and that additional PhoP-regulated genes contribute to magainin 2 resistance .
The ugtL and pmrA genes mediate PhoP-controlled resistance to polymyxin B. A. Percentage survival of wild-type ( 14028s ) , phoP ( MS7953s ) and ugtL ( EG13682 ) strains after incubation with polymyxin B ( 1.0 mg ml-1 ) .
The ugtL and pmrA genes mediate PhoP-controlled resistance to polymyxin B. A. Percentage survival of wild-type ( 14028s ) , phoP ( MS7953s ) and ugtL ( EG13682 ) strains after incubation with polymyxin B ( 1.0 mg ml-1 ) .
In addition to ugtL , PhoP-regulated magainin 2 resistance requires the pagP and yqjA genes ( Fig. 2C ) .
The PhoP-regulated ugtL gene mediates the formation of a monophosphorylated lipid-A .
two genes -- ugtL -- are both transcriptionally regulated by the PhoP
Transcriptional control of the antimicrobial peptide resistance ugtL gene by the Salmonella PhoP .
Transcriptional control of the antimicrobial peptide resistance ugtL gene by the Salmonella PhoP .
Shi Y , Groisman E-A Transcriptional control of the antimicrobial peptide resistance ugtL gene by the Salmonella PhoP .
Shi Y , Groisman EA Transcriptional control of the antimicrobial peptide resistance ugtL gene by the Salmonella PhoP .
Shi Y , Groisman EA Transcriptional control of the antimicrobial peptide resistance ugtL gene by the Salmonella PhoP .
Two StpA-repressed PhoP-dependent genes _ bound by ugtL
The S. Typhimurium ugtL are regulated by a similar mechanism , involving the response regulator of the PhoP/PhoQ two-component system .
The S. Typhimurium ugtL are regulated by a similar mechanism , involving the response regulator of the PhoP/PhoQ two-component system .
The S. Typhimurium ugtL are regulated by a similar mechanism , involving PhoP .
To identify the PhoP-regulated gene ( s ) responsible for motility on 0.3 % agarose low Mg2 + media , we tested the behavior of strains mutated in each of 19 different PhoP-activated genes ( mgtA , mgtB , mgtC , mig-14 , pagC , pagK , pagM , pagN , pagO , pagP , pcgL , pgtE , phoN , pmrD , rstA , slyA , ugtL , virK , and yobG ) .
Transcriptional control of the antimicrobial peptide resistance ugtL gene by the Salmonella PhoP .