Molecular Dynamics Simulation of the Adsorption of a Fibronectin Module on a Graphite Surface

详细信息    查看全文

• 作者：Giuseppina Raffaini and Fabio Ganazzoli
• 刊名：Langmuir
• 出版年：2004
• 出版时间：April 13, 2004
• 年：2004
• 卷：20
• 期：8
• 页码：3371 - 3378
• 全文大小：320K
• 年卷期：v.20,no.8(April 13, 2004)
• ISSN：1520-5827

文摘

We report atomistic simulations of the adsorption of a fibronectin type I module on a hydrophobicgraphite surface. This module comprises only ages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-sheets, unlike the albumin fragments previously investigatedby us which contained only ages/gifchars/alpha.gif" BORDER=0>-helices (Raffaini, G.; Ganazzoli, F. Langmuir 2003, 19, 3403-3412). As donein the latter case, most simulations are carried out in an effective dielectric medium by energy minimizationsand molecular dynamics (MD). Further optimizations and MD runs in the explicit presence of water arealso performed to assess the stability of the geometries found and to describe the solvation of the adsorbedfibronectin module. The initial adsorption is accompanied by local rearrangements of the strands in contactwith the surface, but the overall molecular structure is largely preserved. Much larger rearrangementstake place at longer times as found through the MD runs, with the molecule spreading as much as possibleso as to maximize the surface coverage, hence the interaction energy, despite a significant strain energy.Energetic aspects of adsorption together with the concomitant size change are discussed in comparisonwith our previous results for two albumin fragments.