Characterization of aBacillus subtilis germination mutant with pleiotropic alterations in spore coat structure

One class of spore germination mutants ofBacillus subtilis produces lysozymesensitive spores with altered surface structure. These mutations were pleiotropic in that the pattern of soluble and insoluble spore coat proteins was extensively changed with the virtual absence of a major 12kd polypeptide. Reversion to the lysozyme-resistant phenotype (and wild-type spore coat profile) at or near the site of the original mutation occurred at a frequency consistent with an initial point mutation.The 12kd protein was also absent from extracts of sporulating cells of the mutant although antigens of 14kd and 32kd protein cross-reacting with antibody to the 12kd polypeptide were detected. The 32kd antigen was also present in extracts of sporulating cells but not in the extracts of the spore coat of the wild type and is probably a precursor. Improper processing of such a precursor could account for the extensive alterations of coat structure.