Woodruff W H, Norton K A, Swanson B I, Fry H A
Proc Natl Acad Sci U S A. 1984 Feb;81(4):1263-7. doi: 10.1073/pnas.81.4.1263.
Resonance Raman spectra of spinach plastocyanin and Pseudomonas aeruginosa azurin were studied as a function of temperature between 10 K and 300 K. The spectra are markedly improved both in signal/noise ratio and in resolution at low temperatures. The assignments of the resonance Raman-active vibrations are reinterpreted in view of the number and intensities of peaks observed in the low-temperature spectra. Features appear in the low-temperature spectra of azurin that may be due to copper-bound methionine. The plastocyanin spectra undergo a transition between 220 K and the melting point of water that results in dramatically narrowed peaks at lower temperature and a shift in the carbon-sulfur stretching frequency of the copper-bound cysteine, suggesting a structural change in the active site and an accompanying effect on vibrational dephasing. Considering that the structures and nonvibrational spectroscopies of these two proteins are similar, the substantial differences in the resonance Raman spectra are striking and significant.
研究了菠菜质体蓝素和铜绿假单胞菌天青蛋白在10 K至300 K温度范围内的共振拉曼光谱。在低温下，光谱的信噪比和分辨率都有显著提高。根据低温光谱中观察到的峰的数量和强度，重新解释了共振拉曼活性振动的归属。天青蛋白的低温光谱中出现的特征可能归因于与铜结合的甲硫氨酸。质体蓝素光谱在220 K和水的熔点之间经历了一个转变，这导致在较低温度下峰显著变窄，以及与铜结合的半胱氨酸的碳硫伸缩频率发生位移，表明活性位点发生了结构变化，并对振动去相产生了伴随影响。考虑到这两种蛋白质的结构和非振动光谱相似，共振拉曼光谱中的显著差异是惊人且重要的。
