Molecular investigation of the interaction between ionic liquid type gemini surfactant and lysozyme: A spectroscopic and computational approach. Issue 7 (July 2015) - Maurya, Jitendra Kumar
ABSTRACT Herein, we are reporting the interaction of ionic liquid type gemini surfactant, 1, 4‐bis(3‐dodecylimidazolium‐1‐yl) butane bromide ([C12−4‐C12im]Br2) with lysozyme by using Steady state fluorescence, UV‐visible, Time resolved fluorescence, Fourier transform‐infrared (FT‐IR) spectroscopy techniques in combination with molecular modeling and docking method. The steady state fluorescence spectra suggested that the fluorescence of lysozyme was quenched by [C12−4‐C12im]Br2 through static quenching mechanism as confirmed by time resolved fluorescence spectroscopy. The binding constant for lysozyme‐[C12−4‐C12im]Br2 interaction have been measured by UV‐visible spectroscopy and found to be 2.541 × 105M−1. The FT‐IR results show conformational changes in the secondary structure of lysozyme by the addition of [C12−4‐C12im]Br2. Moreover, the molecular docking study suggested that hydrogen bonding and hydrophobic interactions play a key role in the protein‐surfactant binding. Additionally, the molecular dynamic simulation results revealed that the lysozyme‐[C12−4‐C12im]Br2 complex reaches an equilibrium state at around 3 ns. © 2015 Wiley Periodicals, Inc. Biopolymers 103: 406–415, 2015.