Bloch W, Bickar D
J Biol Chem. 1978 Sep 10;253(17):6211-7.
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.
在两个温度和两个离子强度条件下，通过平衡透析法研究了无机磷酸盐在pH 8时与大肠杆菌碱性磷酸酶的可逆、非共价结合。结合时，每个二聚体酶分子与两个磷酸根离子的化学计量比为1:2，且单一解离常数对温度或离子强度不太敏感。这些结果与已发表的关于无机磷酸盐与碱性磷酸酶反协同结合的证据相矛盾。文中给出了理由，认为其他研究人员报道的明显反协同性是人为造成的。
