Revealing two important tryptophan residues with completely different roles in a dye-decolorizing peroxidase from Irpex lacteus F17.
Revealing two important tryptophan residues with completely different roles in a dye-decolorizing peroxidase from Irpex lacteus F17.
复制标题
DOI：
10.1186/s13068-021-01978-y
复制
发表时间：
2021-05-31
影响因子：
6.3
通讯作者：
He C
中科院分区：
文献类型：
--
作者：
Li L;Wang T;Chen T;Huang W;Zhang Y;Jia R;He C
染料脱色过氧化物酶（DyPs）是一类以H2 O2为最终电子受体的血红素过氧化物酶家族，具有催化氧化多种有机物的功能。通过异源表达获得的来自Irpex lacteus F17的DyP（Il-DyP 4，对应于GenBank MG 209114）对酚类化合物表现出高催化效率，并且对各种合成染料表现出强脱色能力。然而，参与底物氧化的酶结构和催化残基仍然知之甚少。在这里，我们获得了Il-DyP 4的高分辨率结构（2.0 μ m，PDB：7 D8 M），具有α-螺旋，反平行β-折叠和夹在两个结构域之间的一个铁血红素辅因子。Il-DyP 4的晶体结构揭示了两个血红素通道，从酶分子表面通向其血红素区域，并且还显示了四个保守的氨基酸残基，形成了将过氧化氢转化为水分子的口袋。此外，我们通过定点突变和电子顺磁共振（EPR）研究发现，Trp 264和Trp 380是Il-DyP 4中两个重要的具有不同作用的残基。Trp 264是一种非催化残基，主要用于维持Il-DyP 4的血红素区域的正常空间构象和血红素Fe 3+的高自旋态，而Trp 380则作为表面暴露的自由基形成残基，与底物的氧化密切相关，不仅包括大体积染料，还包括简单的酚类。该研究对于深入了解真菌DyPs的催化性质及其结构与功能的关系具有重要意义。在线版本包含补充材料，可在10.1186/s13068-021-01978-y获得。
Dye-decolorizing peroxidases (DyPs) represent a novel family of heme peroxidases that use H2O2 as the final electron acceptor to catalyze the oxidation of various organic compounds. A DyP from Irpex lacteus F17 (Il-DyP4, corresponding to GenBank MG209114), obtained by heterologous expression, exhibits a high catalytic efficiency for phenolic compounds and a strong decolorizing ability toward various synthetic dyes. However, the enzyme structure and the catalytic residues involved in substrate oxidation remain poorly understood. Here, we obtained a high-resolution structure (2.0 Å, PDB: 7D8M) of Il‑DyP4 with α-helices, anti-parallel β-sheets and one ferric heme cofactor sandwiched between two domains. The crystal structure of Il‑DyP4 revealed two heme access channels leading from the enzyme molecular surface to its heme region, and also showed four conserved amino acid residues forming the pocket for the conversion of hydrogen peroxide into the water molecule. In addition, we found that Trp264 and Trp380, were two important residues with different roles in Il‑DyP4, by using site-directed mutagenesis and an electron paramagnetic resonance (EPR) study. Trp264 is a noncatalytic residue that mainly is used for maintaining the normal spatial conformation of the heme region and the high-spin state of heme Fe3+ of Il‑DyP4, while Trp380 serves as the surface-exposed radical-forming residue that is closely related to the oxidation of substrates including not only bulky dyes, but also simple phenols. This study is important for better understanding the catalytic properties of fungal DyPs and their structure–function relationships. The online version contains supplementary material available at 10.1186/s13068-021-01978-y.
登录
查看更多内容
影响因子：
4.8
作者：
Pfanzagl, Vera;Nys, Kevin;Obinger, Christian
通讯作者：
Obinger, Christian
绘制木质素分解过氧化物酶中的长程电子转移途径图
影响因子：
3.3
作者：
Acebes, Sandra;Ruiz-Duenas, Francisco J.;Guallar, Victor
通讯作者：
Guallar, Victor
影响因子：
14.9
作者：
Koua D;Cerutti L;Falquet L;Sigrist CJ;Theiler G;Hulo N;Dunand C
通讯作者：
Dunand C
影响因子：
12.9
作者：
Brissos, Vania;Tavares, Diogo;Martins, Ligia O.
通讯作者：
Martins, Ligia O.
影响因子：
2.9
作者：
Chattopadhyay, K;Mazumdar, S
通讯作者：
Mazumdar, S