Crystal structure of human thioesterase superfamily member 2
Crystal structure of human thioesterase superfamily member 2
复制标题
人硫酯酶超家族成员2的晶体结构。
DOI：
10.1016/j.bbrc.2006.08.025
复制
发表时间：
2006-10-13
影响因子：
3.1
通讯作者：
Gong, Weimin
中科院分区：
文献类型：
--
作者：
Cheng, Zhongjun;Song, Feng;Gong, Weimin
热狗折叠已经在1000多种蛋白质中被鉴定，但其中许多在真核生物中的研究较少。以前没有人硫酯酶超家族成员2（hTHEM 2）的结构或功能研究的报道。由于hTHEM 2与大肠杆菌PaeA蛋白具有约20%的序列同一性，因此提出其为具有热狗折叠的硫酯酶。在这里，我们报告的晶体结构的重组hTHEM 2，确定由单波长异常色散方法在2.3埃的分辨率。这种结构表明hTHEM 2确实包含热狗折叠，并与其他热狗蛋白形成背靠背四聚体。基于结构和序列保守性，预测了hTHEM 2的硫酯酶活性位点。结构和底物特异性与细菌苯乙酰辅酶A水解酶的结构和底物特异性最相似。Asp 65位于亚基B的中心α-螺旋上，通过定点突变显示对催化是必需的。(c)2006年爱思唯尔公司All rights reserved.
Hotdog-fold has been identified in more than 1000 proteins, yet many of which in eukaryotes are less studied. No structural or functional studies of human thioesterase superfamily member 2 (hTHEM2) have been reported before. Since hTHEM2 exhibits about 20% sequence identity to Escherichia coli PaaI protein, it was proposed to be a thioesterase with a hotdog-fold. Here, we report the crystallographic structure of recombinant hTHEM2, determined by the single-wavelength anomalous dispersion method at 2.3 angstrom resolution. This structure demonstrates that hTHEM2 indeed contains a hotdog-fold and forms a back-to-back tetramer as other hotdog proteins. Based on structural and sequence conservation, the thioesterase active site in hTHEM2 is predicted. The structure and substrate specificity are most similar to those of the bacterial phenylacetyl-CoA hydrolase. Asp65, located on the central alpha-helix of subunit B, was shown by site-directed mutagenesis to be essential to catalysis. (c) 2006 Elsevier Inc. All rights reserved.