Enhanced Rigidification within a Double Mutant of Soybean Lipoxygenase Provides Experimental Support for Vibronically Nonadiabatic Proton-Coupled Electron Transfer Models.
Enhanced Rigidification within a Double Mutant of Soybean Lipoxygenase Provides Experimental Support for Vibronically Nonadiabatic Proton-Coupled Electron Transfer Models.
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DOI：
10.1021/acscatal.7b00688
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发表时间：
2017-05-05
期刊：
影响因子：
12.9
通讯作者：
Klinman JP
中科院分区：
文献类型：
--
作者：
Hu S;Soudackov AV;Hammes-Schiffer S;Klinman JP
大豆脂肪氧合酶（SLO）是非绝热氢隧穿反应的原型，因此，已成为许多理论研究的主题。在本工作中，我们报道了一个几乎不依赖于温度的动力学同位素效应（KIE），在六个温度下，SLO的双突变体（DM）的平均KIE值为661 ± 27。的数据是很好地再现内的vibronically非绝热质子耦合电子转移模型，其中的活性位点已成为刚性相比，野生型酶和单位点突变体。一个组合的温度-压力扰动进一步表明，DM-SLO内的温度相关的全球运动更耐高压扰动。这些研究结果提供了强有力的实验支持SLO中的氢隧穿模型，其中局部蛋白质和配体运动和远端构象重排的优化是有效的质子振动波函数之间的基板和活性位点的铁辅因子重叠的先决条件。
Soybean lipoxygenase (SLO) is a prototype for nonadiabatic hydrogen tunneling reactions and, as such, has served as the subject of numerous theoretical studies. In this work, we report a nearly temperature-independent kinetic isotope effect (KIE) with an average KIE value of 661 ± 27 for a double mutant (DM) of SLO at six temperatures. The data are well-reproduced within a vibronically nonadiabatic proton-coupled electron transfer model in which the active site has become rigidified compared to wild-type enzyme and single-site mutants. A combined temperature–pressure perturbation further shows that temperature-dependent global motions within DM-SLO are more resistant to perturbation by elevated pressure. These findings provide strong experimental support for the model of hydrogen tunneling in SLO, where optimization of both local protein and ligand motions and distal conformational rearrangements is a prerequisite for effective proton vibrational wave function overlap between the substrate and the active-site iron cofactor.
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DOI：
10.1073/pnas.0710643105
发表时间：
2008-01-29
影响因子：
11.1
作者：
Meyer, Matthew P.;Tomchick, Diana R.;Klinman, Judith P.
通讯作者：
Klinman, Judith P.
影响因子：
62.1
作者：
Layfield, Joshua P.;Hammes-Schiffer, Sharon
通讯作者：
Hammes-Schiffer, Sharon
影响因子：
15
作者：
Hatcher, E;Soudackov, AV;Hammes-Schiffer, S
通讯作者：
Hammes-Schiffer, S
DOI：
10.1073/pnas.0702188104
发表时间：
2007-06-26
影响因子：
11.1
作者：
Dybala-Defratyka, Agnieszka;Paneth, Piotr;Truhlar, Donald G.
通讯作者：
Truhlar, Donald G.
影响因子：
62.1
作者：
Hammes-Schiffer, Sharon;Stuchebrukhov, Alexei A.
通讯作者：
Stuchebrukhov, Alexei A.