The germination requirements of spores of Clostridium botulinum type E.

Abstract

ABSTRACTThe requirements for, and conditions influencing, the germination of spores of Clostridium botulinum type E were studied in chemically defined media. Spores of this organism germinated rapidly and completely in various combinations of L‐alanine and one of such carbon sources as sugars, lactate, and ribosides in the presence of bicarbonate. The most effective compounds tested were glucose, L‐ and D‐lactate, and inosine. The formation of lactic acid was found to occur during germination of spores in a combination of L‐alanine and glucose. Furthermore, the germination in this medium was strongly inhibited by fluoride or iodoacetate. The germination of spores was also initiated with high concentrations (100 mM or more) of L‐alanine or certain other amino acids alone in the presence of bicarbonate at pH 9.0. The spores germinating in L‐alanine alone and those in L‐alanine plus other compounds were compared as to the minimal concentration of L‐alanine required, pH optimum, temperature optimum for heat‐activation, bicarbonate requirement, and effects of various inhibitors. Significant differences among these characteristics led to a conclusion that different metabolic pathways, operating selectively each germinative compound used, might be involved in the germination of spores of the organism. The mode of action of combination in stimulating germination by the different germinative compounds has been discussed.