Biochemical Studies of Bacterial Sporulation and Germination: VIII. PATTERNS OF ENZYME DEVELOPMENT DURING GROWTH AND SPORULATION OF BACILLUS SUBTILIS

Abstract

The levels of eight enzymes from several different metabolic pathways were determined during growth and sporulation, as well as in the mature spore, of Bacillus subtilis. Three different patterns of development were observed. In one, the levels of DNA polymerase, adenylate kinase, and nucleoside phosphorylase closely followed that of total protein throughout growth and sporulation. In a second pattern, arginase, malic dehydrogenase, and ornithine transcarbamylase were undetectable in log phase cells and appeared only after the end of this period. In the third, aspartic transcarbamylase and IMP dehydrogenase were present during exponential phase but disappeared by the time of appearance of refractile spores. The pattern of development of several of these enzymes was different in an asporogenous, protease-negative strain. The susceptibility of certain of these enzymes to protease activity in extracts was observed, suggesting a possible role for protease elaborated during sporulation. In most instances, the specific activities of the enzymes in the spore were similar to their levels in stationary phase cells at the time of forespore formation. Certain enzymes were absent from spores or were present at very low levels. The results are discussed in relation to possible mechanisms for the origin of proteins found in the spore core.