The three-his triad in Dke1: comparisons to the classical facial triad.
The three-his triad in Dke1: comparisons to the classical facial triad.
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DOI：
10.1021/bi100892w
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发表时间：
2010-08-17
期刊：
影响因子：
2.9
通讯作者：
Solomon, Edward I.
中科院分区：
文献类型：
--
作者：
Diebold, Adrienne R.;Neidig, Michael L.;Moran, Graham R.;Straganz, Grit D.;Solomon, Edward I.
氧活化单核非血红素亚铁酶催化多种化学反应，但通常保持共同的结构基序：两个组氨酸和一个羧酸盐，协调面部三联体中的铁中心。在二酮裂解双加氧酶、Dke1 和半胱氨酸双加氧酶 (CDO) 两种酶中观察到一种新的 FeII 协调三联体，它由三个组氨酸残基组成。通过结合吸收、CD、MCD 和 VTVH MCD 光谱和 DFT 计算，探讨了 Dke1 中的 3 His 基序对 FeII 中心的几何和电子结构的影响。将 3 His 三联体的这种几何和电子结构与 α-酮戊二酸 (αKG) 依赖性双加氧酶克拉维酸合酶 2 (CS2) 和羟苯丙酮酸双加氧酶 (HPPD) 中经典 (2-His-1-羧酸酯) 面部三联体的几何和电子结构进行比较。 FeII 配体场的比较显示 3 His 和 2-His-1-羧酸盐面部三联体位点之间几乎没有差异。 Acac 是 Dke1 的底物，也会与 HPPD 结合，并被确定为强供体，类似于 αKG。 3 His 和 2-His-1-羧酸盐面部三联体位点之间的主要区别在于两种类型三联体观察到的 MLCT 转变，并反映了它们的电荷差异。这些研究深入了解了非血红素亚铁酶的面部三联体连接的扰动对其几何和电子结构的影响以及它们对反应性的可能贡献。
The oxygen activating mononuclear non-heme ferrous enzymes catalyze a diverse range of chemistry yet typically maintain a common structural motif: two histidines and a carboxylate coordinating the iron center in a facial triad. A new FeII coordinating triad has been observed in two enzymes, diketone cleaving dioxygenase, Dke1, and cysteine dioxygenase (CDO) and is composed of three histidine residues. The effect of this 3 His motif in Dke1 on the geometric and electronic structure of the FeII center is explored via a combination of absorption, CD, MCD and VTVH MCD spectroscopies and DFT calculations. This geometric and electronic structure of the 3 His triad is compared to that of the classical (2-His-1-carboxylate) facial triad in the α-ketoglutarate (αKG) dependent dioxygenases clavaminate synthase 2 (CS2) and hydroxyphenylpyruvate dioxygenase (HPPD). Comparison of the ligand fields at the FeII shows little difference between the 3 His and 2-His-1-carboxylate facial triad sites. Acac, the substrate for Dke1, will also bind to HPPD and is determined to be a strong donor, similar to αKG. The major difference between the 3 His and 2-His-1-carboxylate facial triad sites is in MLCT transitions observed for both types of triads and reflects their difference in charge. These studies provide insight into the effects of perturbation of the facial triad ligation of the non-heme ferrous enzymes on their geometric and electronic structure and their possible contributions to reactivity.
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影响因子：
15
作者：
Neidig, ML;Kavana, M;Solomon, EI
通讯作者：
Solomon, EI
影响因子：
15
作者：
Neidig, Michael L.;Brown, Christina D.;Solomon, Edward I.
通讯作者：
Solomon, Edward I.
影响因子：
15
作者：
Pavel, EG;Kitajima, N;Solomon, EI
通讯作者：
Solomon, EI
DOI：
10.1016/s0006-291x(02)02182-4
发表时间：
2002-09-20
影响因子：
3.1
作者：
Straganz, G;Brecker, L;Ribbons, DW
通讯作者：
Ribbons, DW
影响因子：
2.9
作者：
Brownlee, JM;Johnson-Winters, K;Moran, GR
通讯作者：
Moran, GR