PURIFICATION AND PARTIAL CHARACTERIZATION OF PEPTIDASE-1, A SEX-LINKED ENZYME IN PLEURODELES WALTL (URODELE AMPHIBIAN)

Peptidase-1 is a sex-linked enzyme, which can be purified from the liv er of the amphibian urodele Pleurodeles waltl. We estimated its appare nt molecular-mass as 170 kDa by gel filtration chromatography. The enz yme is composed of two subunits with apparent molecular masses of 90 a nd 99 kDa. it is strongly inhibited by ethylenediaminotetraacetic acid , ethylene glycol bis(beta-aminoethyl ether)-N,N-tetraacetic acid, and 1,10-phenanthroline, indicating that peptidase-l is a metallopeptidas e. Peptidase-l has optimal activity at 55 degrees C and pH 8.5. This a cidic enzyme displays two apparent isoelectric points, at 4.9 and 5.2, and is essentially located in the cytosolic subcellular fraction.