cholerae there is a probable third source of (p) ppGpp synthesis.
Recent studies indicate that CgtA is involved in maintaining steady-state level of (p) ppGpp during exponential growth (9).
The Escherichia coli GTPase [CgtA.sub.E] cofractionates with the 50S ribosomal subunit and interacts with spoT, a ppGpp synthetase/hydrolase.
DksA affects ppGpp induction of RpoS at a translational level.
DksA potentiates direct activation of amino acid promoters by ppGpp. Proc Natl Acad Sci USA 2005; 102: 7823-8.
ppGpp with DksA controls gene expression in the locus of enterocyte effacement (LEE) pathogenicity island of enterohaemorrhagic Escherichia coli through activation of two virulence regulatory genes.
151) DksA, an RNA polymerase-interacting transcription factor, inhibits transcription of fis by increasing the sensitivity to ppGpp
, another RNA polymeraseinteracting nucleotide transcription factor.