Drug modulation of water-heme interactions in low-spin P450 complexes of CYP2C9d and CYP125A1.
Drug modulation of water-heme interactions in low-spin P450 complexes of CYP2C9d and CYP125A1.
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DOI：
10.1021/bi501402k
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发表时间：
2015-02-10
期刊：
影响因子：
2.9
通讯作者：
Bowman, Michael K.
中科院分区：
文献类型：
--
作者：
Conner, Kip P.;Cruce, Alex A.;Krzyaniak, Matthew D.;Schimpf, Alina M.;Frank, Daniel J.;de Montellano, Paul Ortiz;Atkins, William M.;Bowman, Michael K.
唑类和吡啶类化合物通常被掺入靶向细胞色素P450（CYP）的小分子抑制剂支架中，作为增加药物结合亲和力、赋予异构体依赖性选择性和改善代谢稳定性的策略。CYP-抑制剂复合物的光学吸收光谱被广泛用于推断这些抑制剂是否直接连接到血红素铁作为催化惰性，低自旋（II型）复合物。在这里，我们表明，药物代谢CYP 2C 9变体和4-（3-苯基丙基）-1H-1，2，3-三唑（PPT）之间的低自旋复合物保留了轴向水配体，尽管表现出“经典”II型光学行为的元素。氢的轴向水配体的脉冲电子顺磁共振（EPR）光谱观察到的两个无和无约束力的物种，并显示抑制剂结合不取代轴向水。一个15 N标记纳入PPT是0.444 nm的血红素铁，表明PPT也在活性位点。来自结核分枝杆菌的CYP 125 A1的反向I型抑制剂LP 10，从X射线晶体结构已知形成低自旋水桥复合物，通过EPR和可见光和近红外磁性圆二色光谱发现，以保留溶液中复合物中的轴向水配体。
Azoles and pyridines are commonly incorporated into small molecule inhibitor scaffolds that target cytochromes P450 (CYPs) as a strategy to increase drug binding affinity, impart isoform-dependent selectivity, and improve metabolic stability. Optical absorbance spectra of the CYP–inhibitor complex are widely used to infer whether these inhibitors are ligated directly to the heme iron as catalytically inert, low-spin (type II) complexes. Here, we show that the low-spin complex between a drug-metabolizing CYP2C9 variant and 4-(3-phenyl-propyl)-1H-1,2,3-triazole (PPT) retains an axial water ligand despite exhibiting elements of “classic” type II optical behavior. Hydrogens of the axial water ligand are observed by pulsed electron paramagnetic resonance (EPR) spectroscopy for both inhibitor-free and inhibitor-bound species and show that inhibitor binding does not displace the axial water. A 15N label incorporated into PPT is 0.444 nm from the heme iron, showing that PPT is also in the active site. The reverse type I inhibitor, LP10, of CYP125A1 from Mycobacterium tuberculosis, known from X-ray crystal structures to form a low-spin water-bridged complex, is found by EPR and by visible and near-infrared magnetic circular dichroism spectroscopy to retain the axial water ligand in the complex in solution.
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影响因子：
2.9
作者：
Pearson, MM;Rogers, D;Chapman, SW
通讯作者：
Chapman, SW
影响因子：
5.6
作者：
POULOS, TL;FINZEL, BC;HOWARD, AJ
通讯作者：
HOWARD, AJ
无底物细胞色素P450中轴向水结扎的强度取决于同工型。
影响因子：
2.9
作者：
Conner, Kip P.;Schimpf, Alina M.;Cruce, Alex A.;McLean, Kirsty J.;Munro, Andrew W.;Frank, Daniel J.;Krzyaniak, Matthew D.;de Montellano, Paul Ortiz;Bowman, Michael K.;Atkins, William M.
通讯作者：
Atkins, William M.
影响因子：
2.9
作者：
Roberts, Arthur G.;Yang, Jing;Halpert, James R.;Nelson, Sidney D.;Thummel, Kenneth T.;Atkins, William M.
通讯作者：
Atkins, William M.
影响因子：
15
作者：
Dikanov, SA;Xun, LY;Bowman, MK
通讯作者：
Bowman, MK