Quenching of fluorescence by meclizine, a probe study for structural and conformational changes in human serum albumin

J Biomol Struct Dyn. 2017 Nov;35(14):3161-3175. doi: 10.1080/07391102.2016.1245159. Epub 2016 Nov 10.

Abstract

The goal of this study was to investigate the interactions between meclizine (MEC) and human serum albumin (HSA) under physiological conditions by different spectroscopies and molecular modeling technique. The drug, MEC quenched the intrinsic fluorescence of HSA and the analysis of the results revealed that static quenching mechanism. The binding of MEC quenches the HSA fluorescence; stoichiometry was 1:1 interaction. Thermodynamic quantities were calculated at different temperatures suggested that hydrophobic and van der Waals interaction with HSA-MEC. The molecular distance, r, between donor and acceptor was estimated according to Forster's theory of non-radiation energy transfer. CD and FT-IR studies confirm changes of secondary structure of HSA. Molecular docking studies validate MEC molecule interact to HSA in sub domain IIA.

Keywords: Forster’s energy transfer; circular dichroism; human serum albumin; meclizine; molecular docking.

MeSH terms

  • Binding Sites
  • Circular Dichroism
  • Humans
  • Ligands
  • Meclizine / chemistry*
  • Models, Molecular*
  • Molecular Conformation*
  • Protein Binding
  • Serum Albumin, Human / chemistry*
  • Spectrometry, Fluorescence
  • Spectroscopy, Fourier Transform Infrared
  • Thermodynamics

Substances

  • Ligands
  • Meclizine
  • Serum Albumin, Human