title: Relation between D-glucose and L- and D-alanine in the initiation of germination of Bacillus subtilis spore.
abstract: The rate of L-alanine-initiated germination of Bacillus subtilis spore was measured by both loss of heat resistance and loss of turbidity, and the effect of glucose on the germination response to a wide range of concentrations of the germinant was analyzed in the presence and absence of D-alanine, an inhibitor. Glucose stimulated L-alanine germination by means of a cooperative effect: glucose increased the affinity of L-alanine by about 3-fold and the rate of germination by about 1.3-fold. However, glucose had little effect on the binding affinity of D-alanine. The apparent binding constant of L-alanine to the spore, which was determined by the next measurable event in the trigger reaction, was 1.2 X 10(-5), that of D-alanine was 6 X 10(-6), and that of glucose was 5 X 10(-5). The relation between the binding site for glucose and those for L- and D-alanine on the spore is discussed. Effect of glucose analogs was also examined.
mesh_terms: D000409:Alanine / Q000378:metabolism / Q000494:pharmacology*; D001412:Bacillus subtilis / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D001665:Binding Sites / Q000187:drug effects; D002241:Carbohydrates / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005947:Glucose / Q000378:metabolism / Q000494:pharmacology*; D007700:Kinetics; D013171:Spores, Bacterial / Q000187:drug effects / Q000378:metabolism; D013237:Stereoisomerism; D013997:Time Factors
chemical_list: D002241:Carbohydrates; D005947:Glucose; D000409:Alanine