Heterodimeric aminopeptidase A from Bacillus licheniformis NS115.

An aminopeptidase A (EC 3.4.11.7) was purified to homogeneity from Bacillus licheniformis NS115 and its enzymatic properties were characterized. The enzyme had an apparent molecular mass of 64 kDa, consisting of heterodimeric 42 kDa and 22 kDa subunits, and is a new enzyme from N-terminal analysis of heavy and light subunits. The light subunit had no catalytic activity against the substrate and apparent K(m) values of heavy and whole enzyme were 0.26 and 0.087 mM of gamma-glutamyl-p-nitroanilide, respectively.