Crystal structure of the probable haloacid dehalogenase PH0459 from Pyrococcus horikoshii OT3
Crystal structure of the probable haloacid dehalogenase PH0459 from Pyrococcus horikoshii OT3
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DOI：
10.1110/ps.051922406
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发表时间：
2006-02-01
期刊：
影响因子：
8
通讯作者：
Yokoyama, S
中科院分区：
文献类型：
--
作者：
Arai, R;Kukimoto-Niino, M;Yokoyama, S
PH0459，来自超嗜热古菌 Pyrococcus horikoshii OT3。是一种可能的卤代酸脱卤酶，分子量为 26,725 Da。在这里..我们报告了通过多波长反常色散法测定的 PH0459 (PDB ID: 1X42) 的 2.0 埃晶体结构。核心结构域具有由六链平行 P 片形成的 α/β 结构，两侧有六个 a 螺旋和三个 3(10) 螺旋。尽管 PH0459 似乎是一种细胞内蛋白质，但一个二硫键 Cys186-Cys212 在 α 螺旋和 3(10) 螺旋之间形成桥梁。插入核心结构域的子结构域具有四螺旋束结构。晶体堆积表明 PH0459 作为单体存在。结构同源性搜索显示 PH0459 类似于来自假单胞菌属的 L-2-卤酸脱卤酶 L-DEX YL。来自自养黄杆菌 GJ10 的 YL 和 Dh1B。活性位点比较表明PH0459可能具有卤酸脱卤酶活性，但其底物特异性可能不同。此外，PH0459 中的二硫键可能有助于单体形式的邻近区域的结构稳定。尽管 L-DEX YL 和 Dh1B 中的相应区域可以通过二聚化来稳定。由于热稳定脱卤酶可用于卤代脂肪族化合物的解毒。 PH0459将成为生物技术研究的有用靶点。
PH0459, from the hyperthermophilic archaeon Pyrococcus horikoshii OT3,. is a probable haloacid dehalogenase with a molecular mass of 26,725 Da. Here.. we report the 2.0 angstrom crystal structure of PH0459 (PDB ID: 1X42) determined by the multiwavelength anomalous dispersion method. The core domain has an alpha/beta structure formed by a six-stranded parallel P-sheet flanked by six a-helices and three 3(10)-helices. One disulfide bond, Cys186-Cys212,, forms a bridge between an alpha-helix and a 3(10)helix, although PH0459 seems to be an intracellular protein. The subdomain inserted into the core domain has a four-helix bundle structure. The crystal packing suggests that PH0459 exists as a monomer. A structural homology search revealed that PH0459 resembles the L-2-haloacid dehalogenases L-DEX YL from Pseudomonas sp. YL and Dh1B from Xanthobacter autotrophicus GJ10. A comparison of the active sites Suggested that PH0459 probably has haloacid dehalogenase activity, but its substrate specificity may be different. In addition, the disulfide bond in PH0459 probably facilitates the structural stabilization of the neighboring, region in the monomeric form. although the corresponding regions in L-DEX YL and Dh1B may be stabilized by dimerization. Since heat-stable dehalogenases can be used for the detoxification of halogenated aliphatic compounds,. PH0459 will be a useful target for biotechnological research.