DUAL EFFECT OF AMINO-ACIDS ON THE DEVELOPMENT OF INTRACELLULAR PROTEOLYTIC ACTIVITY IN THE IRREVERSIBLE SPORULATION PHASE OF BACILLUS-MEGATERIUM

Amino acids added to a population of Bacillus megaterium immediately a fter its transfer to a sporulation medium stimulated growth, delayed s porulation by 1 h, and delayed the development of intracellular cytopl asmic serine proteinase (ISP) activity. However, the ISP activity in l ate sporulation stages exceeded twice that of the control population. Amino acids supplemented at T-3, i.e., at the time when engulfed fores pores were developing, caused a decrease of specific ISP activity. The course of the phenylmethane sulfonyl fluoride (PMSF)-resistant activi ty in the cytoplasm was not affected by amino acids. Intracellular deg radation of proteins prelabeled at the end of the growth phase was dec reased by amino acids during the reversible sporulation phase but was only slightly affected later.