Structural insight into human Zn(2+)-bound S100A2 from NMR and homology modeling.
Structural insight into human Zn(2+)-bound S100A2 from NMR and homology modeling.
复制标题
通过 NMR 和同源建模对人 Zn(2 ) 结合 S100A2 的结构进行深入了解。
DOI：
10.1006/bbrc.2001.5793
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发表时间：
2001
影响因子：
3.1
通讯作者：
Chazin,WJ
中科院分区：
文献类型：
--
作者：
Randazzo,A;Acklin,C;Schäfer,BW;Heizmann,CW;Chazin,WJ
EF-手蛋白的S100亚家族的特征在于除了Ca 2+之外还结合Zn 2+。为了了解Zn ~（2+）在调节S100蛋白活性中的作用，我们对Zn ~（2+）结合的S100 A2进行了异相NMR研究，获得了接近完整的共振归属。该分析揭示了由于脯氨酸残基在蛋白质的柔性区域中的顺反异构而导致的多种异构体之间的平衡。利用核磁共振化学位移指数（CSI）技术测定了S100 A2的二级结构。发现该蛋白具有与其他S100蛋白如S100 A6和S100 B基本相同的二级结构。基于其他S100蛋白的高分辨率三维结构，已经建立了同源性模型。该模型预测了两个Zn 2+结合簇，一个涉及残基His 17-Cys 21-Cys 93，另一个涉及Cys 2-His 39，并且Cys 86参与N-末端或C-末端结合位点。
The S100 subfamily of EF-hand proteins is distinguished by the binding of Zn2+in addition to Ca2+. In an effort to understand the role of Zn2+in modulating the activity of S100 proteins, we have carried out heteronuclear NMR studies of Zn2+-bound S100A2 and obtained near complete resonance assignments. This analysis revealed an equilibrium between multiple isoforms due to cis-trans isomerism of proline residues in flexible regions of the protein. The secondary structure of S100A2 has been determined based on the NMR chemical shift index (CSI) technique. The protein is found to possess essentially the same secondary structure found in other S100 proteins such as S100A6 and S100B. Homology models have been built based on the high resolution three-dimensional structures of other S100 proteins. The models predict two Zn2+binding clusters, one involving residues His17-Cys21-Cys93 and the other Cys2-His39, and with Cys86 participating in either the N-terminal or the C-terminal binding site.