[Purification and partial characterization of an extracellular aminopeptidase of a collagenolytic bacterium: Empedobacter collagenolyticum].

An aminopeptidase was purified from the culture filtrates of a collagenolytic bacterium Empedobacter collagenolyticum. Purification of this enzyme was accomplished by ammonium sulphate precipitation, gel filtration on Sephadex-G200 and chromatography on DEAE-Sephacel. The purified enzyme seemed homogeneous on polyacrylamide gel electrophoresis. The molecular weight of the enzyme was about 100,000 daltons as determined by gel filtration on Sephadex-G200 but it was only 33,000 daltons by disc gel electrophoresis in the presence of sodium dodecyl sulphate. This enzyme selectively hydrolysed N-terminal arginine and lysine residues of peptides and arylamides substrates. The enzyme was strongly inhibited by EDTA, ZnCl2 and L-arginine.