This is small family of Bacillus DegS proteins. The DegS-DegU two-component regulatory system of Bacillus subtilis controls various processes that characterise the transition from the exponential to the stationary growth phase, including the induction of extracellular degradative enzymes, expression of late competence genes and down-regulation of the sigma D regulon [1]. The family also contains one sequence Swiss:Q8R9D3 from Thermoanaerobacter tengcongensis which are described as sensory transduction histidine kinases.

1: Bacillus subtilis functional genomics: genome-wide analysis of the DegS-DegU regulon by transcriptomics and proteomics. Mader U, Antelmann H, Buder T, Dahl MK, Hecker M, Homuth G; Mol Genet Genomics 2002;268:455-467. PMID:12471443