Chemical composition and heat resistance of some aerobic bacterial spores.

Walker, Homer W. (Iowa State University of Science and Technology, Ames), Jack R. Matches, and John C. Ayres. Chemical composition and heat resistance of some aerobic bacterial spores. J. Bacteriol. 82:960-966. 1961.-Analyses of spores of Bacillus species for nitrogen, carbohydrate, dipicolinic acid, and phosphorus showed little correlation with heat resistance. However, as the molar concentration of magnesium increased in relation to dipicolinic acid and calcium concentrations, heat resistance generally decreased. Analyses of several batches of spores indicated that this relationship between calcium, magnesium, and dipicolinic acid did not always hold true. Therefore, while these materials apparently play an important role, other factors need to be included before a full explanation of thermal stability of spores can be made.