Region 2 of sigma-70 is the most conserved region of the entire protein. All members of this class of sigma-factor contain region 2. The high conservation is due to region 2 containing both the -10 promoter recognition helix and the primary core RNA ...
Region 2 of sigma-70 is the most conserved region of the entire protein. All members of this class of sigma-factor contain region 2. The high conservation is due to region 2 containing both the -10 promoter recognition helix and the primary core RNA polymerase binding determinant. The core binding helix, interacts with the clamp domain of the largest polymerase subunit, beta prime [1,2]. The aromatic residues of the recognition helix, found at the C-terminus of this domain are though to mediate strand separation, thereby allowing transcription initiation [1,2].
The general stress response sigma factor in alphaproteobacteria, sigma EcfG is inactivated by the anti-sigma factor NepR, which is itself regulated by the response regulator PhyR. NepR forms two helices that extend over the surface of the PhyR subdom ...
The general stress response sigma factor in alphaproteobacteria, sigma EcfG is inactivated by the anti-sigma factor NepR, which is itself regulated by the response regulator PhyR. NepR forms two helices that extend over the surface of the PhyR subdomains. Homology modeling and comparative analysis of NepR, PhyR and sigmaEcfG mutants indicate that NepR contacts both proteins with the same determinants, showing sigma factor mimicry at the atomic level. This entry represents NepR domains found in alphaproteobacteria [1].
