Nature and functional implications of the cytochrome a3 transients after photodissociation of CO-cytochrome oxidase.
Nature and functional implications of the cytochrome a3 transients after photodissociation of CO-cytochrome oxidase.
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CO-细胞色素氧化酶光解离后细胞色素 a3 瞬态的性质和功能意义。
DOI：
10.1073/pnas.88.6.2588
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发表时间：
1991
影响因子：
11.1
通讯作者：
Kliger,DS
中科院分区：
文献类型：
--
作者：
Woodruff,WH;Einarsdóttir,O;Dyer,RB;Bagley,KA;Palmer,G;Atherton,SJ;Goldbeck,RA;Dawes,TD;Kliger,DS
Time-resolved electronic absorption, infrared, resonance Raman, and magnetic circular dichroism spectroscopies are applied to characterization of the intermediate that is formed within 20 ps after photodissociation of CO from cytochrome a3 in reduced cytochrome oxidase. This intermediate decays with the same half-life (approximately 1 microseconds) as the post-photodissociation CU+B-CO species previously observed by time-resolved infrared. The transient UV/visible spectra, kinetics, infrared, and Raman evidence suggest that an endogenous ligand is transferred from CuB to Fea3 when CO binds to CuB, forming a cytochrome a3 species with axial ligation that differs from the reduced unliganded enzyme. The time-resolved magnetic circular dichroism results suggest that this transient is high-spin and, therefore, five-coordinate. Thus we infer that the ligand from CuB binds on the distal side of cytochrome a3 and displaces the proximal histidine imidazole. This remarkable mechanistic feature is an additional aspect of the previously proposed "ligand-shuttle" activity of the CuB/Fea3 pair. We speculate as to the identity of the ligand that is transferred between CuB and Fea3 and suggest that the ligand shuttle may play a functional role in redox-linked proton translocation by the enzyme.
细胞色素氧化酶：合成
DOI：
--
发表时间：
1981
期刊：
影响因子：
--
作者：
M. Wikström;K. Krab;M. Saraste
通讯作者：
M. Saraste
嗜热栖热菌细胞色素 c1aa3 a 的 A 蛋白基因的分离和部分序列
影响因子：
5.2
作者：
J. Fee;M. W. Mather;P. Springer;S. Hensel;G. Buse
通讯作者：
G. Buse