We report atomistic simulations
of the adsorption
of a fibronectin type I module on a hydrophobicgraphite surface. This module comprises only
![](/im<font color=)
ages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-sheets, unlike the albumin fragments previously investigatedby us which contained only
![](/im<font color=)
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.