Comparing the Interactions and Structural Changes in Milk Carrier Protein of -Lactoglobulin upon Binding of 5-Fluorouracil and Oxali-palladium

Leilabadi-Asl, Amineh; Divsalar, Adeleh; Saboury, Ali Akbar; Parivar, Kazem

Comparing the Interactions and Structural Changes in Milk Carrier Protein of -Lactoglobulin upon Binding of 5-Fluorouracil and Oxali-palladium

Document Type : Article

Authors

¹ Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran

² Department of Cell & Molecular Biology, Faculty of Biological Sciences, Kharazmi University, Tehran, Iran

³ Institute of Biochemistry and Biophysics, University of Tehran, Tehran, Iran

Abstract

β-lactoglobulin (β-LG) is the major protein in the whey of ruminant milk and it can be used as a carrier for anticancer drugs. In this study, the comparison interaction of two chemotherapeutic anti-cancer drugs of 5-Fluorouracil and oxali-palladium with milk carrier protein of β-LG was investigated using fluorescence spectroscopy. The analysis of fluorescence spectra showed that the addition of the 5-Fluorouracil and oxali-palladium to β-LG solution led to a significant reduction in the intrinsic fluorescence spectra of protein and then quenched it. The binding sites and thermodynamic parameters of 5-Fluorouracil and oxali-palladium on the protein were calculated by analyzing of van’t Hoff equation at different temperatures. Binding results have represented that there are 2 and 1binding sites on β-LG for binding of 5-Fluorouracil and oxali-palladium at physiological temperature, respectively. According to the results, van der Waals and hydrogen bonding have the main role of the interactions of β-LG with oxali-palladium, while electrostatic interactions have a major role in the interaction of β-LG with 5-Fluorouracil. Finally, regard to the above results, it can be concluded that the anticancer drugs of 5-Fluorouracil and oxali-palladium can bind to the carrier protein of β-LG and changed the structure of it differently.

Graphical Abstract