Study of interaction between polyphenolic compounds and protein using computational and capillary electrophoresis techniques

Abstract

The present work involves the interaction studies of chiral compounds with the Human Serum Albumin (HSA) protein using computational and experimental methods. The HSA protein has multiple binding sites that forms the basis for its exceptional ability to interact with many organic and inorganic molecules, which makes this protein an important regulator of intercellular fluxes and the pharmacokinetic behaviour of many drugs. This study was undertaken to evaluate the related pharmacokinetic and enantioselective binding parameters of the racemic catechin enantiomers with the HSA. Accordingly, this work involved a method development for the chiral separation of a racemic compound, by capillary electrophoresis-electrokinetic chromatography (CE-EKC) with a highly sulphated beta-cyclodextrin (HS--CD) as a chiral selector. The experimental work was supported by two molecular docking studies. The first included the mimicking of the host-guest interactions between a chiral selector and an enantiomeric compound. The second study included the estimation of the pseudo enantioselective (ES) binding of catechin to HSA. Overall, it was found that CE-EKC is the preferred method for the(±)-catechin binding to HSA protein evaluation. Moreover, the technique used in this work is not restricted to HSA or polyphenols, but can also be applied to other proteins and ligands that possess chirality. Furthermore, the molecular docking approaches also proved to be very useful for the evaluation of chiral recognition systems and for elucidation of the ligand-protein interactions.