Crystal structure and biochemical features of dye-decolorizing peroxidase YfeX from Escherichia coli O157 Asp143 and Arg232 play divergent roles toward different substrates.
Crystal structure and biochemical features of dye-decolorizing peroxidase YfeX from Escherichia coli O157 Asp143 and Arg232 play divergent roles toward different substrates.
复制标题
DOI：
10.1016/j.bbrc.2017.01.081
复制
发表时间：
2017-02
影响因子：
3.1
通讯作者：
Xiuhua Liu;Zenglin Yuan;Jiaxu Wang;Yaqi Cui;Shuang Liu;Yinliang Ma;L. Gu;Sujuan Xu
中科院分区：
文献类型：
--
作者：
Xiuhua Liu;Zenglin Yuan;Jiaxu Wang;Yaqi Cui;Shuang Liu;Yinliang Ma;L. Gu;Sujuan Xu
来自大肠杆菌 O157 的 YfeX 是一种细菌染料脱色过氧化物酶，既具有染料脱色活性又具有典型的过氧化物酶活性。我们以 2.09 Å 分辨率报道了与血红素结合的 YfeX 的晶体结构。 YfeX 单体类似于铁氧还蛋白样折叠并包含两个结构域。血红素基团周围的三个保守残基是 His215、Asp143 和 Arg232。 His215 充当血红素铁原子的近端轴向配体。生化数据表明，保守的Asp143和Arg232的催化意义取决于底物类型，并且YfeX可能对不同的底物采取不同的催化机制。此外，观察到从蛋白质分子表面到血红素远端区域有一条通道，它作为H2O2进入和结合的通道。
YfeX fromEscherichia coliO157 is a bacterial dye-decolorizing peroxidase that represents both dye-decoloring activity and typical peroxidase activity. We reported the crystal structure of YfeX bound to heme at 2.09 Å resolution. The YfeX monomer resembles a ferredoxin-like fold and contains two domains. The three conserved residues surrounding the heme group are His215, Asp143and Arg232. His215functions as the proximal axial ligand of the heme iron atom. Biochemical data show that the catalytic significance of the conserved Asp143and Arg232depends on the substrate types and that YfeX may adopt various catalytic mechanisms toward divergent substrates. In addition, it is observed that an access tunnel spans from the protein molecular surface to the heme distal region, it serves as the passageway for the entrance and binding of the H2O2.