Schweitzer-Stenner R, Wedekind D, Dreybrodt W
Biophys J. 1986 May;49(5):1077-88. doi: 10.1016/S0006-3495(86)83736-5.
The dispersion of the depolarization ratio of oxidation and spinmarker lines of oxyhemoglobin at low C1- concentration (less than 0.08 M) have been examined for different pH values in the acid and alkaline region. Interpreting the depolarization ratio dispersion curves by fifth order Loudon theory of the polarizibility tensor, we obtain tensor parameters depending linearly on symmetry classified distortions of the functional hemegroup. The pH dependence of these parameters are explained by assuming the influence of three titrable groups with pK = 7.8, 6.6, and 5.8 on the heme. Using these pK values, we are able to interpret the pH dependence of CO(O2)-dissociation and CO-association of the fourth hemoglobin subunit. We conclude from our measurements that the change of the Tyr HC2 beta-configuration induces heme-apoprotein interaction via the Tyr HC2 beta-Val FG5 beta H-bond, which are transduced to the heme via central and peripheral coupling.
在低氯离子浓度（小于0.08M）下，研究了酸性和碱性区域不同pH值时氧合血红蛋白氧化和自旋标记线去极化率的分散情况。用极化率张量的五阶劳登理论解释去极化率分散曲线，我们得到了线性依赖于功能性血红素基团对称分类畸变的张量参数。通过假定pK值分别为7.8、6.6和5.8的三个可滴定基团对血红素的影响来解释这些参数的pH依赖性。利用这些pK值，我们能够解释第四个血红蛋白亚基的CO（O2）解离和CO结合的pH依赖性。我们从测量结果得出结论，Tyr HC2β构型的变化通过Tyr HC2β-Val FG5β氢键诱导血红素-载脂蛋白相互作用，该相互作用通过中心和外周耦合传导至血红素。
