Defining the Structural Consequences of Mechanism-Based Inactivation of Mammalian Cytochrome P450 2B4 Using Resonance Raman Spectroscopy
Defining the Structural Consequences of Mechanism-Based Inactivation of Mammalian Cytochrome P450 2B4 Using Resonance Raman Spectroscopy
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DOI：
10.1021/ja910276s
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发表时间：
2010-02-10
影响因子：
15
通讯作者：
Kincaid, James R.
中科院分区：
文献类型：
--
作者：
Mak, Piotr J.;Zhang, Haoming;Kincaid, James R.
鉴于细胞色素 P450 中间体的有效氧化强度，某些底物会产生能够攻击血红素或关键远端口袋蛋白残基的反应性物质，从而在基于机制 (MB) 失活的过程中不可逆地改变酶，这一结果并不令人惊讶，这一结果可能产生严重的生理后果，导致不良的药物相互作用和毒性。虽然存在记录这些底物片段附着的方法，但更难以深入了解这些修饰酶功能特性改变的结构基础。为了满足更好地了解 MB 抑制的迫切需要，我们在这里报告了共振拉曼光谱的首次应用，以研究炔类抑制剂 4-(叔丁基)苯乙炔对哺乳动物 CYP2B4 截短形式的失活，已知其激活形式附着在 CYP2B4 的远端口袋 T302 残基上。
In view of the potent oxidizing strength of cytochrome P450 intermediates, it is not Surprising that certain Substrates can give rise to reactive species capable of attacking the heme or critical distal-pocket protein residues to irreversibly modify the enzyme in a process known as mechanism-based (MB) inactivation, a result that can have serious physiological consequences leading to adverse drug-drug interactions and toxicity. While methods exist to document the attachment of these substrate fragments, it is more difficult to gain insight into the structural basis for the altered functional properties of these modified enzymes. In response to this pressing need to better understand MB inhibition, we here report the first application of resonance Raman spectroscopy to Study the inactivation of a truncated form of mammalian CYP2B4 by the acetylenic inhibitor 4-(tert-butyl)phenylacetylene, whose activated form is known to attach to the distal-pocket T302 residue of CYP2B4.