||Berger H, Jänig GR, Gerber G, Ruckpaul K, Rapoport SM.(1973). Interaction of haemoglobin with ions. Interactions among magnesium, adenosine 5'-triphosphate, 2,3-bisphosphoglycerate, and oxygenated and deoxygenated human haemoglobin under simulated intracellular conditions. European Journal Of Biochemistry 38(3): 553-562. p. 557 left column top sentence and p. 559 table 4PubMed ID4772673
||Researchers chose the data from (Phillips et al., 1966 PMID 5941264) to calculate the association constants prevailing under physiological conditions (ionic strength 0.15, 37°C). The Kass for the Mg2+ complexes of ATP4- and ATPH3- (MgATP2-, MgATPH1-) are 42.7 and 0.724mM^-1, respectively. The pK values for ATPH3- and MgATPH1- are 6.95 and 5.18, respectively. From these constants and those for NaATP and KATP (Kass˜13M^-1) [refs 25-27 in article] the K'ass was calculated to be 12mM^-1, which is in accordance with electrode measurements [table 2, p. 556 left column].