Young L J
Department of Biochemistry, Rice University, Houston, Texas 77251.
Biochemistry. 1988 Jul 12;27(14):5115-21. doi: 10.1021/bi00414a025.
Kinetic and equilibrium binding studies using optically correlated, quantitative electron paramagnetic resonance (EPR) spectroscopy are reported for the reaction of a modified Volpe-Caughey preparation of bovine heart cytochrome c oxidase with anionic (F-, CN-) and gaseous (NO) ligands. A fast phase of cyanide and fluoride ligation can be attributed to an EPR-silent conformer(s), while the slow and medium phases of cyanide binding are correlated with the g = 12 conformer(s). Using dioxygen or ferricyanide, it is possible to modulate reciprocally the relative amounts of these two species, that together account for at least 95% of the active-site conformers of the resting form of the enzyme.
本文报道了使用光学相关定量电子顺磁共振（EPR）光谱对改良的Volpe-Caughey法制备的牛心细胞色素c氧化酶与阴离子（F-、CN-）和气态（NO）配体反应进行的动力学和平衡结合研究。氰化物和氟化物结合的快速阶段可归因于一种EPR沉默构象体，而氰化物结合的慢速和中速阶段与g = 12构象体相关。使用氧气或铁氰化物，可以相互调节这两种构象体的相对含量，它们共同构成了该酶静止形式活性位点构象体的至少95%。
