Studies on Human Urinary Enzymes and Inhibitors

Abstract

Urinary enzymes and inhibitors were concentrated by using several methods, such as membrane filter, polyethyleneglycol, ion exchange, bentonite, celite, silica gel, and Arg-Sepharose columns. Of these methods, Arg-Sepharose adsorption was shown to be the most suitable for the concentration method. One liter of normal human urine concentrated by Arg-Sepharose column contained not only esterase activities on Nα-acetylglycyl-L-lysine methyl ester (AGLMe); 9.15, p-tosyl-L-arginine methyl ester (TAMe); 3.00, N-acetyl-L-arginie methyl ester (AAMe); 2.33, Nα-benzoyl-L-arginine ethyl ester (BAEe); 2.01, p-tosyl-L-lysine methyl ester (TLMe); 1.47, and N-acetyl-L-tyrosine ethyl ester (ATEe); 0.55 μmol/min, but also very strong anti-trypsin activity (inhibiting 5,049 μg of trypsin). The AGLMe hydrolyzing enzyme showed two peaks with molecular weights of 54,000 and above 100,000 on using gel filtration on Sephadex G-200, both of which had plasminogen activating activity and were completely neutralized by anti-urokinase antiserum, and were thought to be urokinase. The TAMe hydrolyzing enzyme was thought to be kallikrein, which corresponded to a molecular weight of 43,000 and had strong kinin-producing activity. Urinary trypsin inhibitor showed a molecular weight of 67,000 and migrated to the serum prealbumin fraction on Pevikon block electrophoresis at pH 8.6. From the substrate spectrum and the enzyme recovery of the urine concentrate the possibility of the presence of some other new urinary enzymes and inhibitors was also suggested.