ABSTRACT
In silico analysis of the complete Bacillus subtilis genome revealed the presence of three genes whose deduced amino acid sequences exhibit an alpha-crystallin domain characteristic for the family of small heat shock proteins: cotM (which has already been identified [Henriques et al. (1997) J. Bacteriol 179, 1887-1897]), yocM, and cotP (formerly ydfT). Analysis of the expression of all three genes by slot-blot experiments and by transcriptional fusions revealed that none of them was heat-inducible. Transcription of cotP was induced late during sporulation by the sporulation-specific sigma factor sigma(K) and negatively controlled by the GerE repressor. No expression of the yocM gene was found under all standard laboratory conditions tested. Both a cotP knockout mutant as well as a cotM cotP double knockout turned out to be viable and form spores and exhibited no germination defect.