title: Purification and characterization of intestinal alkaline phosphatase from harp seal.
abstract: 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.
authors.affiliation: Laboratory of Biologically Active Substances of Hydrobionts, Ministry of Health, Moscow, USSR.
authors.lastname: Sakharov IYu
authors.forename: I E
authors.initials: IE
authors.lastname: Makarova
authors.forename: G A
authors.initials: GA
authors.lastname: Ermolin
mesh_terms: 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
chemical_list: D002412:Cations; D000469:Alkaline Phosphatase