Molecular Docking Characterization of a Four-Domain Segment of Human Fibronectin Encompassing the RGD Loop with Hydroxyapatite

Fibronectin adsorption on biomaterial surfaces plays a key role in the biocompatibility of biomedical implants. In the current study, the adsorption behavior of the 7–10th type III modules of fibronectin (FN-III(7–10)) in the presence of hydroxyapatite (HAP) was systematically investigated by using molecular docking approach. It was revealed that the FN-III(10) is the most important module among FN-III(7–10) in promoting fibronectin binding to HAP by optimizing the interaction energy; the arginine residues were observed to directly interact with the hydroxyl group of HAP through electrostatic forces and hydrogen bonding. Moreover, it was found that the HAP-binding sites on FN-III(10) are mainly located at the RGD loop region, which does not affect the interaction between the fibronectin protein and its cognate receptors on the cell surface.