The catalytic pathway of cytochrome P450cam at atomic resolution
The catalytic pathway of cytochrome P450cam at atomic resolution
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DOI：
10.1126/science.287.5458.1615
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发表时间：
2000-03-03
期刊：
影响因子：
56.9
通讯作者：
Sligar, SG
中科院分区：
文献类型：
--
作者：
Schlichting, I;Berendzen, J;Sligar, SG
细胞色素P450超家族的成员在生理温度下催化分子氧与未活化的烃的加成反应，该反应需要在没有催化剂的情况下在高温下进行。用捕集技术和冷冻色谱法测定了樟脑与P450 cam羟基化反应中三个中间体的结构。使用0.91埃波长的X射线确定了P450 cam的二价铁分子加合物的结构;用1.5埃的X射线照射会导致二价铁分子分解为与氧铁基物种一致的中间体。结构显示在几个重要的残基的构象变化，并揭示了一个网络的结合水分子，可能提供所需的质子的反应。
Members of the cytochrome P450 superfamily catalyze the addition of molecular oxygen to nonactivated hydrocarbons at physiological temperature-a reaction that requires high temperature to proceed in the absence of a catalyst. Structures were obtained for three intermediates in the hydroxylation reaction of camphor by P450cam with trapping techniques and cryocrystallography. The structure of the ferrous dioxygen adduct of P450cam was determined with 0.91 angstrom wavelength x-rays; irradiation with 1.5 angstrom x-rays results in breakdown of the dioxygen molecule to an intermediate that would be consistent with an oxyferryl species. The structures show conformational changes in several important residues and reveal a network of bound water molecules that may provide the protons needed for the reaction.