Phosphate binding to Escherichia coli alkaline phosphatase. Evidence for site homogeneity.
The reversible, noncovalent binding of inorganic phosphate to Escherichia coli alkaline phosphatase at pH 8 has been examined by equilibrium dialysis at two temperatures and two ionic strengths. Binding occurs with a stoichiometry of two phosphate ions per dimeric enzyme molecule and a single dissociation constant that is not very sensitive to temperature or ionic strength. These results contradict published evidence for anti-cooperative binding of inorganic phosphate to alkaline phosphatase. Reasons are presented for believing that the apparent anti-cooperativity reported by other workers is artifactual.
D000469:Alkaline Phosphatase / Q000378:metabolism; D001665:Binding Sites; D004926:Escherichia coli / Q000201:enzymology*; D007700:Kinetics; D009994:Osmolar Concentration; D010710:Phosphates; D011485:Protein Binding
D010710:Phosphates; D000469:Alkaline Phosphatase