On the other hand , the transcriptional regulator Crp , previously described as an activator of hlyE transcription in Escherichia coli , is involved in transcriptional repression of hlyE in S. Typhi .
The Crp regulator is involved in transcriptional repression of S. Typhi hlyE Crp is a transcriptional regulator previously reported to be an activator of hlyE transcription in E. coli .
increased b-galactosidase activity in comparison with the parental strain _ suggesting that Crp is involved in downregulation of hlyE transcription in S. Typhi
All these results together suggest that Crp is involved in downregulation of hlyE in S. Typhi .
Moreover , the addition of glucose to the growth medium results in decreasing the hlyE mRNA , suggesting that there is another factor related to catabolite-repression , different from Crp , involved in downregulation of hlyE Fig. 2 .
In addition , we found that Crp is involved in downregulation of hlyE in S. Typhi .
Crp is involved in transcriptional repression of S. Typhi hlyE .
Nevertheless , addition of glucose to the growth medium results in a decrease of hlyE mRNA in S. Typhi Δcrp mutant , suggesting that there is another factor related to catabolite-repression , different from CRP , involved in down-regulation of hlyE in S. Typhi .
Nevertheless , genetic experiments showed that CRP participates in the negative regulation of hlyE in S. Typhi since crp deletion led to increased β-galactosidase activit .
Fis participate in the repression of hlyE transcription by repressing rpoS transcription To find out whether CRP is repressing hlyE expression through a direct binding to the respective promoter region , we performed a shift mobility assay .
CRP participate in the repression of hlyE transcription by repressing rpoS transcription To find out whether CRP is repressing hlyE expression through a direct binding to the respective promoter region , we performed a shift mobility assay .
CRP participate in the repression of hlyE transcription by repressing rpoS transcription To find out whether CRP is repressing hlyE expression through a direct binding to the respective promoter region , we performed a shift mobility assay .
Thus , CRP might repress hlyE expression by repressing rpoS in S. Typhi .