Laws W R, Shore J D
J Biol Chem. 1979 Apr 25;254(8):2582-4.
Resonance energy transfer from Trp-314 to ionized Tyr-286 was proposed (Laws, W. R., and Shore, J. D. (1978) J. Biol. Chem. 253, 8593-8597) as the mechanism for the observed decrease in protein fluorescence of liver alcohol dehydrogenase seen with alkaline pH, or with the formation of a ternary complex with NAD+ and trifluoroethanol. In the present study, ultraviolet difference spectra confirm the presence of ionized tyrosine not only in these two cases but also in the ternary complex with NADH and isobutyramide. Our results indicate that ternary complex formation, with either oxidized or reduced coenzyme, causes a conformational change leading to partial ionization of tyrosine residues in regions of the enzyme far from the active site.
有人提出（Laws, W. R., and Shore, J. D. (1978) J. Biol. Chem. 253, 8593 - 8597），从色氨酸-314到离子化酪氨酸-286的共振能量转移是肝脏乙醇脱氢酶在碱性pH条件下或与NAD⁺和三氟乙醇形成三元复合物时观察到的蛋白质荧光降低的机制。在本研究中，紫外差光谱证实不仅在这两种情况下存在离子化酪氨酸，而且在与NADH和异丁酰胺形成的三元复合物中也存在。我们的结果表明，与氧化型或还原型辅酶形成三元复合物会导致构象变化，从而导致酶中远离活性位点区域的酪氨酸残基部分离子化。
