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蛋白质可以影响晶体的成核及生长速率,从而改变晶体的形貌和习性,因此了解牙釉蛋白在羟基磷灰石(HAP)表面的相互作用对于了解牙齿的生长机理具有重要意义.采用分子动力学(MD)和操控式分子动力学(SMD)相结合的方法研究了六个不同取向的富亮氨酸牙釉蛋白(LRAP)在HAP(010)晶面的吸附-脱附行为.在MD模拟中筛选出关键的吸附残基,并通过SMD模拟中的脱附时间对其进行分类.研究发现Glu56和Asp58是两个出现概率较高的吸附残基,其中Asp58在六个体系中都发挥了主要的吸附作用.我们进一步对吸附位点的作用基团和作用形式进行分析,发现酸性氨基酸侧链上的羧基基团与HAP表面钙离子的静电相互作用是最主要的作用形式.羧基上的两个氧原子可以钳住"钙离子,从而将LRAP锚定在HAP表面.因此,富含羧基基团的氨基酸是HAP晶型控制的首选残基.
Protein can affect the nucleation and growth rate of crystal, and thus change the morphology and habit of crystal, so to understand the interaction of amelogenin on the surface of hydroxyapatite (HAP) is of great significance to understand the growth mechanism of teeth.Using molecular dynamics Adsorption-desorption behaviors of six different oriented leucine-rich amelogenin (LRAP) on HAP (010) crystal planes were studied by a combination of MD and manipulated molecular dynamics (SMD) The key adsorption residues were screened out by simulation and classified by SMD desorption time.It was found that Glu56 and Asp58 were two adsorption residues with higher probability of occurrence, of which Asp58 played a role in all six systems We further analyzed the active groups and the action forms of the adsorption sites and found that the electrostatic interactions between the carboxyl groups on the acid amino acid side chains and the calcium ions on the HAP surface are the most important forms of action Of the two oxygen atoms can clamp the calcium ion to anchor the LRAP to the HAP surface.Thus, carboxyl-rich amino acids are the preferred residues for HAP crystal form control.