Structure of the uncomplexed DNA repair enzyme endonuclease VIII indicates significant interdomain flexibility.
Structure of the uncomplexed DNA repair enzyme endonuclease VIII indicates significant interdomain flexibility.
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未复杂的DNA修复酶内核酸内切核酸酶VIII的结构表明域间柔韧性明显。
DOI：
10.1093/nar/gki796
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发表时间：
2005
影响因子：
14.9
通讯作者：
Shoham G
中科院分区：
文献类型：
--
作者：
Golan G;Zharkov DO;Feinberg H;Fernandes AS;Zaika EI;Kycia JH;Grollman AP;Shoham G
大肠杆菌内切酶VIII （Nei）从DNA中切除氧化嘧啶。它与细菌8-氧鸟嘌呤糖基化酶Fpg具有显著的序列同源性和相似的机制。共价Nei-DNA复合物的结构最近被确定，揭示了对DNA结合和催化重要的关键氨基酸残基。几个Fpg结构也被报道过；然而，由于缺乏来自同一来源的非络合酶和dna结合酶的结构，阻碍了Fpg/Nei家族蛋白的结构动力学分析。我们报道了自由野生型Nei的2.8 Å分辨率结构及其失活突变体Nei- e2a （2.3 Å）和Nei- r252a （2.05 Å）的两个结构。这三种结构实际上是相同的，这表明突变并没有影响蛋白质在自由状态下的整体构象。与DNA的Nei结构相比，该结构显示出明显的构象变化，反映了酶的两个主要结构域的旋转~ 50°。这种结构域间的灵活性以前没有报道过任何DNA糖基化酶，这可能是这类酶中DNA诱导的全局构象变化的第一个证据。一些局部但功能相关的结构变化在酶的其他部分也很明显。
Escherichia coli endonuclease VIII (Nei) excises oxidized pyrimidines from DNA. It shares significant sequence homology and similar mechanism with Fpg, a bacterial 8-oxoguanine glycosylase. The structure of a covalent Nei–DNA complex has been recently determined, revealing critical amino acid residues which are important for DNA binding and catalysis. Several Fpg structures have also been reported; however, analysis of structural dynamics of Fpg/Nei family proteins has been hindered by the lack of structures of uncomplexed and DNA-bound enzymes from the same source. We report a 2.8 Å resolution structure of free wild-type Nei and two structures of its inactive mutants, Nei-E2A (2.3 Å) and Nei-R252A (2.05 Å). All three structures are virtually identical, demonstrating that the mutations did not affect the overall conformation of the protein in its free state. The structures show a significant conformational change compared with the Nei structure in its complex with DNA, reflecting a ∼50° rotation of the two main domains of the enzyme. Such interdomain flexibility has not been reported previously for any DNA glycosylase and may present the first evidence for a global DNA-induced conformational change in this class of enzymes. Several local but functionally relevant structural changes are also evident in other parts of the enzyme.
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影响因子：
4.8
作者：
Gilboa, R;Zharkov, DO;Shoham, G
通讯作者：
Shoham, G
影响因子：
4.8
作者：
Jiang, DY;Hatahet, Z;Wallace, SS
通讯作者：
Wallace, SS
影响因子：
2.7
作者：
Buchko, GW;Wallace, SS;Kennedy, MA
通讯作者：
Kennedy, MA
DOI：
10.1107/s0907444998003254
发表时间：
1998-09-01
期刊：
ACTA CRYSTALLOGRAPHICA SECTION D-BIOLOGICAL CRYSTALLOGRAPHY
影响因子：
--
作者：
Brunger, AT;Adams, PD;Warren, GL
通讯作者：
Warren, GL
影响因子：
3.2
作者：
Jiang, DY;Hatahet, Z;Wallace, SS
通讯作者：
Wallace, SS