Zhou Hailong, Wu Tao, Dong Xiuli, Wang Qi, Shen Jiawei
Department of Chemistry, Zhejiang University, Hangzhou 310027, PR China.
Biochem Biophys Res Commun. 2007 Sep 14;361(1):91-6. doi: 10.1016/j.bbrc.2007.06.169. Epub 2007 Jul 16.
Many properties and functions of bone-related proteins perform through the interface with the hydroxyapatite. However, the mechanism of difference of proteins adsorbing behaviors caused by the variation of calcium and phosphate ions on hydroxyapatite is still unclear at atomic level. In this work, we investigated the site-selective adhesion and the adsorption mechanism of protein BMP-7 to the hydroxyapatite surfaces in aqueous media during adsorption and desorption processes. Molecular dynamics (MD) and steered molecular dynamics (SMD) simulations combined with trajectory analysis were employed to give insight into the underlying behaviors of BMP-7 binding. The results suggest that the adsorption sites could be divided into two categories: COO(-) and NH(2)/NH3+. For COO(-), the adsorption phenomenon is driven by the electrostatic interaction formed between the negative charged carboxylate groups and the Ca1 cations on the hydroxyapatite surface. While for NH(2)/NH3+, the interaction is through the intermolecular H-bonds between the N-containing groups and the phosphate on the hydroxyapatite surface.
许多骨相关蛋白的性质和功能是通过与羟基磷灰石的界面来实现的。然而，在原子水平上，由羟基磷灰石上钙和磷酸根离子变化引起的蛋白质吸附行为差异的机制仍不清楚。在这项工作中，我们研究了蛋白质BMP - 7在吸附和解吸过程中在水介质中对羟基磷灰石表面的位点选择性粘附和吸附机制。采用分子动力学（MD）和引导分子动力学（SMD）模拟并结合轨迹分析来深入了解BMP - 7结合的潜在行为。结果表明，吸附位点可分为两类：COO(-)和NH(2)/NH3+。对于COO(-)，吸附现象是由带负电荷的羧基与羟基磷灰石表面的Ca1阳离子之间形成的静电相互作用驱动的。而对于NH(2)/NH3+，相互作用是通过含氮基团与羟基磷灰石表面的磷酸盐之间的分子间氢键实现的。
