Dynamical magnetostructural properties of Anabaena ferredoxin
Dynamical magnetostructural properties of Anabaena ferredoxin
复制标题
鱼腥藻铁氧化还原蛋白的动态磁结构特性
DOI：
--
复制
发表时间：
2007
影响因子：
11.1
通讯作者：
D. Marx
中科院分区：
文献类型：
--
作者：
E. Schreiner;N. N. Nair;R. Pollet;V. Staemmler;D. Marx
在室温下，对氧化鱼腥藻PCC7119铁氧还蛋白的动态磁结构性质进行了量子/经典混合研究。这种蛋白质含有一个[2Fe-2S]簇，其中两个铁中心反铁磁性地耦合到具有真正的多参考特征的整体低自旋电子基态。为了研究这个基团的磁动力学，在密度泛函理论的框架下建立了一个近似的自旋投影法，它允许高效地进行多行列式从头算分子动力学模拟。利用该方案，研究了热涨落和构象运动对[2Fe-2S]团簇结构和反铁磁耦合常数J(T)动力学的影响。除了证明[2Fe-2S]核本身的形状受氢键的影响是多么敏感之外，分析还揭示了J对局部振动和大幅度运动的复杂的动力学耦合。结果表明，这种相互作用可以通过铁-硫团簇和蛋白质骨架之间特定的振动模式和不同的氢键模式来理解。这意味着超越了古德足够-卡纳森规则对氧化铁-硫假体基团的角磁结构关联。
A mixed quantum/classical investigation of the dynamical magnetostructural properties, that is, “magnetodynamics,” of oxidized Anabaena PCC7119 ferredoxin is carried out at room temperature in two distinct conformational states. This protein hosts a [2Fe–2S] cluster in which two iron centers are antiferromagnetically coupled to an overall low-spin electronic ground state that has a genuine multireference character. To study the magnetodynamics of this prosthetic group, an approximate spin projection method is formulated in the framework of density functional theory that allows for multideterminant ab initio molecular dynamics simulations to be carried out efficiently. By using this scheme, the influence of both thermal fluctuations and conformational motion on the structure of the [2Fe–2S] cluster and on the dynamics of the antiferromagnetic coupling constant, J(t), has been investigated. In addition to demonstrating how sensitively the shape of the [2Fe–2S] core itself is affected by hydrogen bonding, the analyses reveal a complex dynamical coupling of J to both local vibrations and large-amplitude motion. It is shown that this interplay can be understood in terms of specific vibrational modes and distinct hydrogen-bonding patterns between the iron–sulfur cluster and the protein backbone, respectively. This implies going beyond the Goodenough–Kanamori rules for angular magnetostructural correlations of oxidized iron–sulfur prosthetic groups.
影响因子：
56.9
作者：
Beinert, H;Holm, RH;Munck, E
通讯作者：
Munck, E