The 1.8-Å Crystal Structure of the N-Terminal Domain of an Archaeal MCM as a Right-Handed Filament
The 1.8-Å Crystal Structure of the N-Terminal Domain of an Archaeal MCM as a Right-Handed Filament
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DOI：
10.1016/j.jmb.2013.12.025
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发表时间：
2014-04-03
影响因子：
5.6
通讯作者：
Chen, Xiaojiang S.
中科院分区：
文献类型：
--
作者：
Fu, Yang;Slaymaker, Ian M.;Chen, Xiaojiang S.
微小染色体维持(MCM)蛋白是真核生物和古生物DNA复制所必需的复制型解旋酶。大多数古生菌只有一个MCM基因。在这里，我们报道了来自古细菌嗜酸热浆(TAPMCM)的N-端MCM的1.8埃晶体结构。在该结构中，MCM N-末端形成一个右手细丝，每圈包含六个亚基，其直径为中央通道开口的25A。内表面带高度正电荷，表明DNA结合。这种每转六个亚基的丝状结构也可能暗示了六聚体MCM的开环结构以及DNA复制起始和延伸阶段的动态构象变化。(C)2014爱思唯尔有限公司。保留所有权利。
Mini-chromosome maintenance (MCM) proteins are the replicative helicase necessary for DNA replication in both eukarya and archaea. Most of archaea only have one MCM gene. Here, we report a 1.8-angstrom crystal structure of the N-terminal MCM from the archaeon Thermoplasma acidophilum (tapMCM). In the structure, the MCM N-terminus forms a right-handed filament that contains six subunits in each turn, with a diameter of 25 A of the central channel opening. The inner surface is highly positively charged, indicating DNA binding. This filament structure with six subunits per turn may also suggests a potential role for an open-ring structure for hexameric MCM and dynamic conformational changes in initiation and elongation stages of DNA replication. (C) 2014 Elsevier Ltd. All rights reserved.