CHARACTERISTICS OF PARTIALLY PURIFIED PROLIDASE AND PROLINASE FROM THE HUMAN PROSTATE

Both prolidase and prolinase from the human prostate were separated in to two peaks by TSK DEAE-5PW chromatography. These peaks of prolidase isozymes I and II differed from each other in their responses to prein cubation with Mn2+, their substrate specificity, optimal pH, and heat stability. The molecular weights of prolidases I and II were estimated to be 110,000 and 165,000, respectively, by gel filtration. Substrate specificity of prolinase peaks I and H was almost the same, but they differed in optimal pH and heat stability. The molecular weights of pr olinases I and II were about 85,000 and 63,000, respectively. These re sults indicate that two isozymes of prolidase and of prolinase, which differ in various characteristics, are present in the human prostate.