Abstract
From the cells of two strains of Bacillus subtilis, one producing liquefying α-amylase and the other, saccharifying α-amylase, were isolated each two kinds, four in total, of aminopeptidases. Their stabilities and activities were different from one another under various conditions, although all of them required either manganese or cobalt ions for the enzyme actions. They were also distinguished from each other by their specificities towards peptide linkages as tested by synthetic peptides. They showed different activities according to the kinds of amino acids of the N-terminus. The experiment also indicated that the hydrolytic activity of the peptidases was influenced by the kind and sequence of amino acids adjacent to the N-terminal amino acid.
