Mechanistic study of lysozyme glycation by fructose and modulation by curcumin derivatives

Glycation can affect the protein conformational changes and direct involvement of advanced glycation end products (AGEs). These products are major cause of many diseases and disorders, such as diabetes and its complications. Curcumin (diferuloymethane) and its derivatives have been exhibited an inhibitory effect on modulation of glycation and oxidative stress. In this work, it is attempted to study the effects of fructose (Fru) on structure and activity of Hen Egg-White Lysozyme (HEWL) as a model protein and modulating by curcumin (Cur) and its derivative, dimethyl curcumin (DMC) via various techniques, such as enzymatic activity assay, fluorescence spectroscopy and ThT assay, circular dichroism spectropolarimetry, transmission electron microscopy (TEM) as well as molecular dynamic simulation and docking studies. The results indicate that Cur and DMC preserve secondary and tertiary structures of lysozyme and they prevent upper and lower loop locking and promote enzymatic activity somewhat by prohibiting the binding of lysine-97 to the lower movable loop of the active site. Moreover, simulation results show a good correlation with the experimental data. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

The study showed that curcumin and its derivatives can preserve the structure of lysozyme and promote enzymatic activity by inhibiting the binding of lysine-97 to a specific site. The simulation results were well correlated with the experimental data.