l -ALANINE DEHYDROGENASE: A MECHANISM CONTROLLING THE SPECIFICITY OF AMINO ACID-INDUCED GERMINATION OF BACILLUS CEREUS SPORES

Abstract

A study has been undertaken of the properties and specificity of germination of spores of Bacillus cereus strain T. In the absence of additional carbon sources, only L-alanine, L-[alpha]-NH2-n-butyric acid, and L-cysteine were effective germinating agents. The physical properties of germination, induced by L-alanine and L-[alpha]-NH2-n-butyric acid following extended heat shock, were in close agreement with those of L-alanine dehydrogenase. The specificity of the germination system, as well as amino acid deamination in vivo, support the view that L-alanine dehydrogenase activity is essential for germination and that the enzyme serves as the initial binding site for the L-alanine in heat-shocked spores.