Ling Yan, Davidson Victor L, Zhang Yong
Department of Chemistry and Biochemistry, University of Southern Mississippi, 118 College Drive #5043, Hattiesburg, MS 39406, USA.
J Phys Chem Lett. 2010;1(19):2936-2939. doi: 10.1021/jz101159x.
Ferryl species are important catalytic intermediates in heme enzymes. A recent experimental investigation of a diheme protein MauG reported the first case of using two Fe(IV) species as an alternative to compound I in catalysis. Both Fe(IV) species have unusual Mössbauer properties, which was found to originate from novel structural features based on a quantum chemical investigation. With comparison to the previously reported Fe(IV)=O and Fe(IV)-OH species, results here provide the first evidence of a couple of new mechanisms by which proteins influence the properties of ferryl species by directly providing the O via Tyr, or stabilizing exogenous O via hydrogen bonding interaction. These results expand our ability to identify and evaluate high-valent heme proteins and models.
高铁物种是血红素酶中重要的催化中间体。最近对双血红素蛋白MauG的一项实验研究报道了首例在催化过程中使用两个Fe(IV)物种替代化合物I的情况。这两个Fe(IV)物种都具有不寻常的穆斯堡尔性质，基于量子化学研究发现这源于新颖的结构特征。与先前报道的Fe(IV)=O和Fe(IV)-OH物种相比，这里的结果首次提供了一些新机制的证据，即蛋白质通过酪氨酸直接提供氧或通过氢键相互作用稳定外源氧来影响高铁物种的性质。这些结果扩展了我们识别和评估高价血红素蛋白及模型的能力。
