This superfamily correspond to the CtsR C-terminal dimerisation domain. CtsR is an important repressor that modulates the transcription of class III stress genes in Gram-positive bacteria, mainly from Firmicute species.CtsR consists of an N-terminal domain, a DNA binding domain with a helix-turn-helix motif (HTH) and a C-terminal dimerisation domain organised in a four helix bundle, with an unknown function. CtsR has a role in forming a complex with DNA, binding to promoter regions of heat-shock genes. It is mainly involved in the regulatory network of the bacterial heat-shock response. The phosphorylation sites reside in the winged HTH domain [].
This superfamily represents the N-terminal winged HTH domain of CtsR, a dimeric repressor. The members include several Firmicute transcriptional repressor of class III stress genes (CtsR) proteins. CtsR of L. monocytogenes negatively regulates the clpC, clpP and clpE genes belonging to the CtsR regulon [].CtsR consists of an N-terminal domain, a DNA binding domain with a helix-turn-helix motif (HTH) and a C-terminal dimerisation domain organised in a four helix bundle, with an unknown function. CtsR has a role in forming a complex with DNA, binding to promoter regions of heat-shock genes. It is mainly involved in the regulatory network of the bacterial heat-shock response. The phosphorylation sites reside in the winged HTH domain [].
This family of bacterial arginine kinases catalyse the transfer of phosphate from ATP to arginine. Protein arginine phosphorylation is involved in the regulation of many critical cellular processes, such as protein degradation, competence and stress responses []. Bacterial protein arginine kinase McsB main targets comprise central factors of the stress response system including the CtsR and HrcA heat shock repressors, as well as major components of the protein quality control system such as the ClpCP protease and the GroEL chaperonine []. McsB has been shown to phosphorylate and inhibit global heat shock repressor CtsR []. Furthermore, McsB is an adaptor for the ClpCP protease. McsB is activated during heat stress by autophosphorylation, allowing the controlled degradation of CtsR by ClpCP []. It is also required for de-localization of competence proteins [].
