文章基本信息

标题：Extended x-ray absorption fine structure of copper in cytochrome c oxidase: Direct evidence for copper—sulfur ligation
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作者：Robert A. Scott ; Stephen P. Cramer ; Robert W. Shaw 等
期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1981
卷号：78
期号：2
页码：664-667
DOI：10.1073/pnas.78.2.664
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：The copper x-ray fluorescence excitation spectrum of cytochrome c oxidase (ferrocytochrome c:oxygen oxidoreductase, EC 1.9.3.1 ) has been recorded in the 245--270 K range. The beat pattern observed in the extended x-ray absorption fine structure can be accounted for only by postulating a combination of sulfur and nitrogen (or oxygen) ligands to the copper. The average Cu--S distance is 2.27 {+/-} 0.02 A and the average Cu--N (or Cu--O) distance is 1.97 {+/-} 0.02 A. The amplitudes require ca, 1-1.5 sulfurs and 2 nitrogens (or oxygens) per copper. The distribution of sulfur ligands between CuA and CuB sites is not known, although there is some evidence that two sulfur atoms are bound to CuA.
关键词：cytochrome aa ₃ ; copper sites ; sulfur ligation ; x-ray absorption spectroscopy ; x-ray fluorescence detection