title: [Phosphoric esters of vitamin D2 and D3, new substrates for alkaline phosphatase of the bovine intestine].
abstract: Phosphate esters of vitamins D2 and D3 (D2-O-P and D3-O-P) are hydrolyzed by the alkaline phosphatase from calf intestine (CAPase). pH optimum and Km values are in agreement with those reported for other substrates for intestinal alkaline phosphatase. No effect of activation was noted at low concentrations of D2-O-P and D3-O-P (10(-5)-10(-4)M) in contrast with that stated in earlier works. At higher concentrations (1-4 mM) of the phosphorilated vitamins, accordingly with their function as substrates of CAPase, an inhibitory effect on the hydrolysis of p-nitrophenylphosphate was observed.
mesh_terms: D000469:Alkaline Phosphatase / Q000378:metabolism*; D000818:Animals; D002417:Cattle; D002762:Cholecalciferol; D004789:Enzyme Activation; D004872:Ergocalciferols; D006868:Hydrolysis; D007422:Intestines / Q000201:enzymology*; D009596:Nitrophenols / Q000378:metabolism; D010755:Organophosphates; D009943:Organophosphorus Compounds / Q000378:metabolism; D010766:Phosphorylation; D013053:Spectrophotometry
chemical_list: D004872:Ergocalciferols; D009596:Nitrophenols; D010755:Organophosphates; D009943:Organophosphorus Compounds; D002762:Cholecalciferol; C008644:nitrophenylphosphate; D000469:Alkaline Phosphatase
vernacular_title: Les esters phosphoriques des vitamines D2 et D3, nouveaux substrats pour la phosphatase alcaline de l'intestin de Boeuf.