Extraction of spore-lytic enzyme from Clostridium perfringens spores

Various chemical reagents known to extract spore coat protein were used to extract spore-lytic enzyme (SLE) from intact and germinated spores of Clostridium perfringens. Of the reagents tested, 7.2 M-urea plus 10% (v/v) mercaptoethanol, pH 2.85, solubilized the most SLE activity per mg spores. The quantity of SLE extracted was dependent on the initial pH of the reagent, with a maximum between pH 2.7 and 3.0. Germinated spores yielded more SLE than non-germinated spores upon urea/mercaptoethanol extraction. SLE release during spore germination probably utilizes a trigger mechanism not satisfied by germination alone. Significant amounts of SLE were released during germination when spores were suspended in potassium chloride or a complex germinant mixture containing brain-heart infusion, yeast extract and chloramphenicol, but not during germination with sodium nitrite, which non-enzymically lysed the cortical peptidoglycan. Greater solubilization of SLE activity was obtained by urea/mercaptoethanol extraction of spores germinated with nitrite than of spores germinated with either potassium chloride or the complex germinant.