Purification and characterization of intestinal alkaline phosphatase from harp seal.
1. Alkaline phosphatase (EC 3.1.3.1.) from harp seal (Phagophilus groenlandicus) has been purified by concanavalin A-Sepharose chromatography to homogeneity with a specific activity of 1200-1500 units/mg of protein. 2. The mol. wt of the enzyme and its subunits were estimated as 260,000 and 70,000, respectively. By chromatofocusing the isoelectric point of this enzyme is 5.5. 3. With p-nitrophenylphosphate, pH-optimum and KM for the enzyme are 9.8 and 0.9 mM, respectively. 4. The enzyme was strongly inhibited by Sn4+, Fe3+ and Zn2+, whereas Mg2+ and Mn2+ were effective activators of the enzyme. Seal alkaline phosphatase was slightly inhibited by high concentrations of Ca2+ and Cr3+. 5. The enzyme activity reached a maximum at 55-60 degrees C. It was shown that the heat stability of seal and calf intestinal alkaline phosphatases were equal at 37 and 56 degrees C.
Sakharov IYu
Laboratory of Biologically Active Substances of Hydrobionts, Ministry of Health, Moscow, USSR.
Makarova
I E
IE
Ermolin
G A
GA
D000469:Alkaline Phosphatase / Q000037:antagonists & inhibitors / Q000302:isolation & purification / Q000378:metabolism*; D000818:Animals; D010872:Caniformia / Q000378:metabolism*; D002412:Cations / Q000494:pharmacology; D002417:Cattle; D006358:Hot Temperature; D007120:Immunochemistry; D007422:Intestines / Q000201:enzymology; D007526:Isoelectric Point; D007700:Kinetics; D008970:Molecular Weight; D046048:Seals, Earless / Q000378:metabolism*; D013045:Species Specificity; D013379:Substrate Specificity
D002412:Cations; D000469:Alkaline Phosphatase