title: Factors that regulate the activity of the phosphatidylinositol kinase present in oocyte membranes of Xenopus laevis.
abstract: 1. Phosphatidylinositol kinase present in the membranes of Xenopus laevis oocytes was characterized. 2. The enzyme requires Mg2+ or Mn2+ at 10 mM and exogenous phosphatidylinositol (50 microM) increases the formation of phosphatidylinositol-4-phosphate. 3. The oocyte phosphatidylinositol kinase cannot use GTP as a phosphate donor but this compound inhibits competitively the utilization of ATP. 4. Addition of phosphatidylserine and phosphatidylinositol-4,5-bisphosphate stimulates the phosphorylation of phosphatidylinositol but 2,3-bisphosphoglycerate at 5 mM concentration is a strong inhibitor of the reaction.
authors.affiliation: Departamento de Bioquimica, Facultad de Medicina, Universidad de Chile, Santiago.
authors.forename: D
authors.initials: D
authors.lastname: Carrasco
authors.forename: C C
authors.initials: CC
authors.lastname: Allende
authors.forename: J E
authors.initials: JE
authors.lastname: Allende
mesh_terms: D019870:1-Phosphatidylinositol 4-Kinase; D019794:2,3-Diphosphoglycerate; D000255:Adenosine Triphosphate / Q000378:metabolism; D000818:Animals; D004163:Diphosphoglyceric Acids / Q000494:pharmacology; D005260:Female; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology; D008345:Manganese / Q000494:pharmacology; D008566:Membranes / Q000378:metabolism; D009865:Oocytes / Q000378:metabolism*; D010716:Phosphatidylinositols / Q000494:pharmacology; D010770:Phosphotransferases / Q000037:antagonists & inhibitors / Q000378:metabolism*; D014982:Xenopus laevis / Q000378:metabolism*
chemical_list: D004163:Diphosphoglyceric Acids; D010716:Phosphatidylinositols; D019794:2,3-Diphosphoglycerate; D008345:Manganese; D000255:Adenosine Triphosphate; D010770:Phosphotransferases; D019870:1-Phosphatidylinositol 4-Kinase; D008274:Magnesium