title: Polyphosphoinositides undergo charge neutralization in the physiological pH range: a 31P-NMR study.
abstract: The charge state of phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate was determined as a function of pH by way of 31P-NMR spectroscopy. The pK values for the first protonation of the phosphomonoester residues in phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate were found to be 6.2 and 6.6, respectively, for the 4-phosphate moiety, and 7.7 for the 5-phosphate moiety.
mesh_terms: D000818:Animals; D002118:Calcium; D002645:Chickens; D004530:Egg Yolk; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D008823:Micelles; D019269:Phosphatidylinositol 4,5-Diphosphate; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols
chemical_list: D008823:Micelles; D019269:Phosphatidylinositol 4,5-Diphosphate; D018129:Phosphatidylinositol Phosphates; D010716:Phosphatidylinositols; C037178:phosphatidylinositol 4-phosphate; D002118:Calcium