Johnson M L
Biochemistry. 1986 Feb 25;25(4):791-7. doi: 10.1021/bi00352a009.
The concept of free energy couplings has been extensively used in studies of the ligand-linked subunit assembly of oligomeric proteins such as human hemoglobin A [cf. Ackers, G. K. (1980) Biophys. J. 32, 331-346]. Recently, the concept of "order" of free energy couplings has been introduced as a description of the number of protein subunits that must be liganded to effect changes in intersubunit interactions [Weber, G. (1984) Proc. Natl. Acad. Sci. U.S.A. 81, 7098-7102]. That report utilized the concept of order of free energy couplings to analyze a set of previously published equilibrium constants derived from data pertaining to the chemical equilibrium between oxygen and stripped hemoglobin A [Mills, F. C., Johnson, M. L., & Ackers, G. K. (1976) Biochemistry 15, 5350-5362]. The Weber report claims to have "unequivocally" demonstrated that the coupling between oxygenation and subunit assembly in hemoglobin A is "first order". In the present report, it is demonstrated that free energy couplings of both the first and second order are capable of describing the original oxygen binding data.
自由能偶联的概念已广泛应用于寡聚蛋白（如人血红蛋白A）的配体连接亚基组装研究中[参见Ackers, G. K. (1980) Biophys. J. 32, 331 - 346]。最近，引入了自由能偶联“阶数”的概念，用于描述为影响亚基间相互作用变化而必须被配体结合的蛋白质亚基数量[Weber, G. (1984) Proc. Natl. Acad. Sci. U.S.A. 81, 7098 - 7102]。该报告利用自由能偶联阶数的概念分析了一组先前发表的平衡常数，这些常数源自与氧气和脱辅基血红蛋白A之间化学平衡相关的数据[Mills, F. C., Johnson, M. L., & Ackers, G. K. (1976) Biochemistry 15, 5350 - 5362]。Weber的报告声称已“明确”证明血红蛋白A中氧合与亚基组装之间的偶联是“一级”的。在本报告中，证明了一级和二级自由能偶联都能够描述原始的氧结合数据。
