The crystal structure of bonito (katsuo) ferrocytochrome c at 2.3 A resolution. II. Structure and function.
The crystal structure of bonito (katsuo) ferrocytochrome c at 2.3 A resolution. II. Structure and function.
复制标题
鲣鱼 (katsuo) 铁细胞色素 c 的晶体结构，分辨率为 2.3 A。
DOI：
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发表时间：
1976
期刊：
影响因子：
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通讯作者：
M. Kakudo
中科院分区：
文献类型：
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作者：
N. Tanaka;T. Yamane;T. Tsukihara;T. Ashida;M. Kakudo
利用X射线衍射技术在2.3A分辨率下对鲣鱼心铁细胞色素c进行了结构分析，并建立了Kendrew型骨架模型。该分子整体呈蛋形，高35 A，宽30 A，厚23 A;血红素铁原子的第5个配体是His-18咪唑环的N-硫原子，第6个是Met-80硫原子。不同的α-螺旋区域存在于N-末端和残基11之间、60和69之间以及90和C-末端之间。本发明分子的构象与马氧化分子的构象之间最明显的差异是Phe-82苯环的位置。在本还原分子中，苯环与铁原子的接触更紧密，并对铁原子的性质产生影响。在分子内部，在血红素口袋的下部，有一个扩展的氢键网络，包括血红素基团的丙酸残基。Phe-82和氢键网络可能在该分子的功能中起关键作用。
The structure analysis of bonito heart ferrocytochrome c was carried out at 2.3 A resolution by X-ray diffraction, and a Kendrew-type skeletal model was built up. This molecule has an overall egg shape, 35 A in height, 30 A in width and 23 A in thickness; the 5th ligand of the heme iron atom is the N-epsilon atom of the His-18 imidazole ring and the 6th is the Met-80 sulfur atom. Distinct alpha-helix regions are found between the N-terminus and reside 11, between 60 and 69, and between 90 and the C-terminus. The most distinct difference between the conformation of the present molecule and that of the horse oxidized molecule is the location of the Phe-82 phenyl ring. In the present reduced molecule, the phyenyl ring is in closer contact with the iron atom and gives influences on the character of the iron atom. Inside the molecule, at the lower part of the heme pocket, there is an extended hydrogen bond network including the propionic acid residues of the heme group. Both Phe-82 and the hydrogen bond network may play a key role in the function of this molecule.