In silico study of the interaction between casein with tocopherols: preliminary evaluation of lipophilic substrate inclusion on proteic matrix

Bovine casein is a family of milk proteins with hydrophilic and hydrophobic regions that show block distribution within the protein chain. These amphiphilic properties offer great potential as a material for being used as a matrix for transport active materials as tocopherol. In this work, we aim to evaluate the interaction of α1-casein, the main fraction of the casein, with vitamin E by docking calculations. Docking studies were conducted by using SwissDock and DockThor servers. Using specific scoring functions based on energy terms were obtained the best protein-ligand binding models. The observed interactions between vitamin E and amino acid residues consisting of several hydrophobic interactions (e.g. with Tyr119, Ala144, Trp179, Met211, Pro212). A few hydrogen bonds were observed between phenyl group of vitamin E and carboxylate group of glutamic acid residue (e.g. with Glu85, Glu148). In conclusion, the results suggest that exists a major interaction of vitamin E with random coil structure that the interaction with segments formed by α-helix and β-sheet. This implies that in random coil segments predominance hydrophobic domains.