Single Molecule Level Investigations on Bone Morphogenetic Proteins Binding to Graphene

Bone morphogenetic proteins (BMP) have osteoinductive activity and therefore play important roles in overcoming bone disorders. The use of the graphene-based scaffolds in bone tissue engineering appears as a good alternative for the autologous and allogeneic bone grafts, metal alloys or ceramics, which are widely used in case of bone injuries. The aim of the present study was to provide a detailed structural characterization of three different most efficient osteoinductive BMP molecules, and to assess their individual interaction properties with the graphene sheet. The critical amino acids involved in BMPgraphene interactions were identified after performing docking simulations. Although the BMP-2, BMP-6 and BMP-7 share structural similarities, important variation in their affinity for graphene sheet was observed. The interaction force of protein-graphene complexes was estimated by performing unbinding simulations. The highest interaction force (1.31 nN) was obtained in case of the BMP-6 graphene complex, whereas the BMP-2 graphene complex has the lowest interaction force (0.25 nN). The information provided here might allow the progress in graphene-based tissue engineering of bones, as well as a better understanding of BMP physiological roles.