Exploring the Binding Stability and Sub Domains of Bovine Serum Albumin (BSA) In the Presence of Phenolic Derivatives of Benzoic Acids and Cinnamic Acids Through Molecular Docking Approach

Abstract

Variation in binding energies and stability of complex between Bovine Serum Albumin (BSA) with hydroxyl derivatives of benzoic acid (DBA) and cinnamic acid (DCA) derived from Psidium guajava L. were studied by employing molecular docking (Mol.Doc) techniques. The binding energies of DCA-BSA show more favorable interactions than that of DBA-BSA complex. Among the DCAs, Caffeic acid (CA) and Coumaric acid (CoA) which possess phenolic –OH  has larger stability compared to Sinapic acid (SA) and Ferrulic acid (FA) wherein the -OH is replaced by -OCH₃ in these acids. On the contrary, in the case of DBAs, the acid containing -OCH₃ (Vanillic acid (VA)) has a better binding efficiency with BSA compared to acids containing -OH although all the DBAs possess lesser energetics compared to DCAs. The variation in their binding energies are attributed to the binding site, sub domains and the nature of the bimolecular interactions between the BSA and guest (DBA and DCA) molecules. FA and SA prefer to dock in the Sudlow binding site II whereas for CA and CoA, the energetically stable site is warfarin site (Site I). Interestingly, for Syringic acid (SyA) and Pyrogallic acid (PyA) the energetically most favored binding sub domain is IB which is the non-Sudlow binding site (III). However, Gentistic acid (GeA) and Procatechiuc acid (PrA) prefers both drug binding sites. Docking studies provides an excellent approach in determining the various forces governing the stability of ligand-protein complexes.