Characterization of intermediate-molecular-weight acid phosphatase from bovine kidney cortex.
The distribution of acid phosphatases of intermediate molecular weight was determined in various mammalian tissues. The intermediate-molecular-weight acid phosphatases (designated P-II-1 and 2) comprised about 25% of the p-nitrophenyl phosphatase activity in the supernatant of bovine kidney cortex homogenate. The P-II-1 and 2 purified 2,000 fold showed the pI values of 5.9 and 5.7, respectively, on isoelectric focusing. Apparent molecular weights of both P-II-1 and 2 were estimated to be 42,000 by Sephadex G-100 gel filtration and 44,000 by SDS-polyacrylamide disc gel electrophoresis. Both the enzymes catalyzed the hydrolysis of a wide variety of natural phosphomonoesters, except for the phosphoproteins phosphoserine and o-phosphocholine. The enzymes showed a high activity on pyridoxal phosphate, beta-glycerophosphate, and 2'-AMP. The optimum activity pH was near 5 with p-nitrophenyl phosphate, but was shifted to the neutral range when pyridoxal phosphate was the substrate. The cations Hg2+ and Ag+ had a marked inhibitory effect. Neither enzyme was inhibited significantly by L-(+)-tartrate or pCMB. The two other types of acid phosphatases, the high-molecular-weight (designated P-I) and low-molecular-weight (designated P-III), were also purified to homogeneity from bovine kidney cortex, and were compared with P-II from several aspects including substrate specificity and susceptibility to various compounds.
D000135:Acid Phosphatase / Q000302:isolation & purification* / Q000378:metabolism; D000818:Animals; D002417:Cattle; D004285:Dogs; D006168:Guinea Pigs; D007527:Isoenzymes / Q000302:isolation & purification / Q000378:metabolism; D007668:Kidney / Q000201:enzymology; D007672:Kidney Cortex / Q000201:enzymology*; D007700:Kinetics; D008970:Molecular Weight; D009928:Organ Specificity; D011817:Rabbits; D051381:Rats; D013045:Species Specificity; D013552:Swine
D007527:Isoenzymes; D000135:Acid Phosphatase