Nonsequence-specific arginine interactions in the nucleosome core particle
Nonsequence-specific arginine interactions in the nucleosome core particle
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DOI：
10.1002/bip.10389
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发表时间：
2003-08-01
期刊：
影响因子：
2.9
通讯作者：
Subirana, JA
中科院分区：
文献类型：
--
作者：
García-Pérez, M;Pinto, M;Subirana, JA
我们分析了核小体核心颗粒中碱性氨基酸侧链对DNA的相对取向。DNA磷酸产生的电场没有明显的择优取向：没有发现精氨酸胍基团的择优取向。精氨酸可以直接与磷酸氧氢键结合，也可以通过范德华接触和局部负电场稳定在小槽中。另一方面，与精氨酸成键的磷酸氧原子总是被发现靠近胍基所定义的平面。由此可以得出结论，精氨酸的相互作用具有很强的方向性，而磷酸盐的相互作用则不是。我们还发现，组蛋白H2B的一个高度带电的片段，位于两个DNA旋转之间，具有非常可变的构象。当与DNA相互作用时，蛋白质正电荷密度的增加显然允许多种非特异性蛋白质构象。(C) 2003 Wiley期刊有限公司
We have analyzed the relative orientation of basic amino acid side chains towards DNA in the nucleosome core particle. The electric field created by DNA phosphates has no apparent preferential orientation: no favored orientation of the arginine guanidinium group is found. Arginine may be either directly hydrogen bonded to a phosphate oxygen or stabilized in the minor groove by van der Waals contacts and the local negative electric field. On the other hand, the phosphate oxygen atoms hydrogen bonded to arginines are always found close to the plane defined by the guanidinium group. Thus it can be concluded that the interactions of arginine are strongly directional, those of phosphate are not. We also find that a highly charged fragment of histone H2B, which is placed between two DNA turns, has a very variable conformation. An increase in protein positive charge density apparently allows multiple nonspecific protein conformations when interacting with DNA. (C) 2003 Wiley Periodicals, Inc.