ABSTRACT
The effect of amino acids on sporulation is discussed. Heat-resistant spores were produced in a chemically defined medium.
Subject(s)
Bacillus/growth & development , Culture Media , Spores/growth & development , Amino Acids , Bacteriological Techniques , Hot Temperature , Magnesium Sulfate , Spores, Bacterial/growth & developmentABSTRACT
The heat resistance, fermentation reactions, nutritional requirements, and phage sensitivity of 18 selected morphological variants of Bacillus stearothermophilus NCA 1518 were studied. It was found that when smooth variants mutated to rough colonial morphology, there was no concurrent change in fermentation reactions, nutritional requirements, or heat resistance. The smooth variant, and the rough mutants derived directly from it, presented a uniform pattern of biochemical capabilities which differed from the pattern presented by the rough variants isolated from the same stock culture. This led to the conclusion that the smooth and rough types previously observed in stocks of B. stearothermophilus NCA 1518 either were carried in the stock since the original isolation or represent a very profound and uncommon mutation, or that one of the variants has been introduced into the stock culture from an extraneous source sometime in the past.
Subject(s)
Bacillus , Genetic Variation , Bacillus/growth & development , Bacillus/metabolism , Bacteriological Techniques , Bacteriophages , Carbohydrate Metabolism , Culture Media , Fermentation , Genetics, Microbial , Hot Temperature , Lysogeny , Microbial Sensitivity Tests , Mutation , Oxygen Consumption , Spores, Bacterial/growth & developmentABSTRACT
Studies of bacteriophages GH5 and GH8 of Bacillus stearothermophilus strain NCA1518 revealed that their properties were sufficiently different from known phages and from each other to indicate that each was a different entity, although no major deviation was demonstrated.