Stavrakis Stavros, Koutsoupakis Konstantinos, Pinakoulaki Eftychia, Urbani Andrea, Saraste Matti, Varotsis Constantinos
Department of Chemistry, University of Crete, 71409 Heraklion, Crete, Greece.
J Am Chem Soc. 2002 Apr 17;124(15):3814-5. doi: 10.1021/ja0169825.
Time-resolved step-scan Fourier infrared spectroscopy has been used to study the CO-bound cbb(3)-type cytochrome c oxidase from Pseudomonas stutzeri at room temperature. We observe a single band in the FTIR spectrum at 1956 cm(-1) (beta-form). The time-resolved data indicate that upon photolysis, CO is transferred from heme b(3) (nu(CO) = 1956 cm(-1)) to CuB (nu(CO) = 2064 cm(-1)). The decay of the 2065 cm(-1) peak (t(1/2) = 120 +/- 16 ms) and the development of the 1956 cm(-1) peak (t(1/2) = 144 +/- 8 ms ) suggest that formation of the Fe-CO complex is concurrent with the decay of the CuB-CO complex. The intensity ratio of the Fe-CO/CuB-CO (2.15) remains constant for all data points, and thus we conclude that no fraction of CO escapes the binuclear center at 293 K.
时间分辨步进扫描傅里叶红外光谱已被用于在室温下研究来自施氏假单胞菌的CO结合的cbb(3)型细胞色素c氧化酶。我们在傅里叶变换红外光谱中观察到在1956 cm(-1)处有一个单峰（β形式）。时间分辨数据表明，光解后，CO从血红素b(3)（ν(CO)=1956 cm(-1)）转移到CuB（ν(CO)=2064 cm(-1)）。2065 cm(-1)峰的衰减（t(1/2)=120±16 ms）和1956 cm(-1)峰的出现（t(1/2)=144±8 ms）表明Fe-CO复合物的形成与CuB-CO复合物的衰减同时发生。Fe-CO/CuB-CO的强度比（2.15）对于所有数据点都保持恒定，因此我们得出结论，在293 K时没有一部分CO逸出双核中心。
