Probing the binding interaction of ortho-vanillin derived chalcone with lysozyme: A biophysical studies aided by in silico calculations

The principal intent of this study is to elucidate the binding interaction between the scaffold Chalcone (C1) and Lysozyme (LYZ) in detail employing biophysical studies aided by in silico calculations. UV-Vis absorption study, Fluorescence, and Time-resolved fluorescence spectroscopy studies indicated the formation of the ground-state complex between C1 and LYZ. Quenching of corrected fluorescence spectra of LYZ in the presence of C1 at varied concentrations has been estimated from Slem-Volmer (SV) plot and Double Logarithmic plot. The binding constant value indicates the moderate affinity of LYZ to the scaffold C1. Time-resolved fluorescence spectroscopy confirmed the static mechanism of quenching. Binding constant, the number of binding sites, and the thermodynamic parameters are also estimated. Conformational changes in the structure of LYZ have been analyzed using Circular Dichroism Spectroscopy. The distance (r(o)) between the acceptor (C1) and donor (LYZ) and critical energy transfer distance (R-o) has been calculated based on Forster non-radiative energy transfer theory. Molecular docking further revealed the existence of hydrogen bonding along with hydrophobic interactions as the primary forces for the formation of a stable complex between LYZ and C1. (C) 2020 Elsevier B.V. All rights reserved.