Proteomic characterization of spore coat protein mutants of Bacillus subtilis

Spore coat proteins play an important role in maintaining spore structure as well as the resistive capacity of the spores. Spore morphogenetic proteins are responsible for layering the proteinaceous layers during spore morphogenesis. Previous studies have analyzed the dependence of certain coat proteins on the well-known morphogenetic proteins such as SpoIVA, CotE, CotH etc. Yet many coat proteins remain to be studied for regulation of their assembly and their dependence on the morphogenetic or other coat proteins. With the aim to map the dependence of coat protein deposition on CotA, CotE, Tgl, we studied protein profiles from the ΔcotA, ΔcotE and Δtgl spores. We identified a subset of coat proteins dependent and/or affected by the absence of the candidate protein genes cotE and tgl in these spores. ΔcotA spores did not show an effect on the overall protein composition of spore coat. The thermals stress resistance tests of ΔcotE and Δtgl mutant spores compared to the wild-type spores showed that Δtgl spores are more resistant to thermal stress than ΔcotE spores. Δtgl spores are compared to the equally thermal resistant spores from control wild-type cells, under our test conditions.