Crystal structure of heat shock locus V (HslV) from Escherichia coli
Crystal structure of heat shock locus V (HslV) from Escherichia coli
复制标题
DOI：
10.1073/pnas.94.12.6070
复制
发表时间：
1997-06-10
影响因子：
11.1
通讯作者：
Huber, R
中科院分区：
文献类型：
--
作者：
Bochtler, M;Ditzel, L;Huber, R
热休克基因座V(HslV；又称ClpQ)是大肠杆菌中依赖于ATP的蛋白水解酶HslVU的蛋白分解核心，它与真核细胞和古细菌蛋白酶体的β亚基具有序列相似性。与这些具有72点对称性的粒子不同，它是具有62点对称性的六角体的二聚体，由同晶取代和对称平均确定的3.8埃分辨率的HSLV的晶体结构表明，尽管粒子的对称性不同，但折叠和亚基之间的接触是保守的。三肽醛抑制剂乙酰亮氨酸去亮氨酸与HslV的N-末端苏氨酸残基结合，可能是半缩醛，在功能上也与古生物和真核生物的蛋白酶体有关。
Heat shock locus V (HslV; also called ClpQ) is the proteolytic core of the ATP-dependent protease HslVU in Escherichia coli, It has sequence similarity with the beta-type subunits of the eukaryotic and archaebacterial proteasomes. Unlike these particles, which display 72-point symmetry, it is a dimer of hexamers with 62-point symmetry, The crystal structure of HslV at 3.8-Angstrom resolution, determined by isomorphous replacement and symmetry averaging, shows that in spite of the different symmetry of the particle, the fold and the contacts between subunits are conserved. A tripeptide aldehyde inhibitor, acetyl-Leu-Leu-norleucinal, binds to the N-terminal threonine residue of HslV, probably as a hemiacetal, relating HslV also functionally to the proteasomes of archaea and eukaryotes.