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Protease production by Clostridium perfringens in batch and continuous culture

Clostridium perfringens C1051 isolated from human faeces was studied to determine physiological and nutritional factors that govern protease production in the colon. In batch culture extracellular protease was formed during exponential growth but ceased in the stationary phase. In both glucose‐ and peptide‐limited chemostats protease activities increased with culture dilution rate. Proteolysis was greatest under glucose limitation at low growth rates (D= 0·1/h to D= 0·35/h), but no difference was found in the relative amounts of protease produced when dilution rates were increased to 0·7/h. In batch culture protease formation was optimal at pH 6·0. Ammonium chloride and glucose concentrations over the range 1–10 g/l had no significant effect on protease production, but high concentrations of peptone were stimulatory.