A novel vision into the binding behavior of curcumin with human serum albumin-holo transferrin complex: molecular dynamic simulation and multi-spectroscopic perspectives

Abstract

In this work, we investigated the simultaneous binding of curcumin (CUR) to human serum albumin (HSA) and human-holo transferrin (HTF) in the roles of binary and ternary systems. The binding affinity and binding site of protein-protein interaction were studied by the methods of multiple spectroscopic and molecular dynamics (MD) simulation. According to the results, the measurements for binding constant of HSA-CUR, HTF-CUR and (HSA-HTF) CUR complexes were observed to be 1.51 × 10⁵, 7.93 × 10⁴ and 1.44 × 10⁵ M⁻¹ respectively. Thermodynamic parameters were considered to be set at three varying temperatures including 298, 303, and 308 K. In conformity to the negative values of ΔH⁰ and ΔS⁰ the significant roles of hydrogen binding and van der-Waals forces in the formation of complexes are quiet evident. The binding distance between Trp residues of HSA, HTF and HSA-HTF upon interaction with CUR, were acquired by applying the Förster’s theory of non-radioactive energy transfer and reported to be 2.04 nm, 1.78 nm, and 1.86 nm, respectively. In accordance with the conductometry and Resonance light scattering (RLS) results, there were different interaction behaviors among the HSA-HTF complex and CUR in ternary system when being compared to the outcomes of binary system. The secondary structure of all three cases increased as the CUR concentration was intensified, which confirmed the inducement of proteins conformational changes through the application of circular dichroism (CD) technique. The experimental results that were acquired throughout the binding of HSA-CUR, HTF-CUR, and (HSA-HTF) CUR complexes were approved by molecular modeling.

Communicated by Ramaswamy H. Sarma

Keywords:

• Human serum albumin
• human holo-transferrin
• curcumin
• spectroscopy
• MD simulation

Acknowledgment

The financial support of Research Council of the Mashhad Brunch, Islamic Azad University, Mashhad, Iran, is gratefully acknowledged.

Disclosure statement

The authors declare no conflict of interest in regard to this article.

Ethical statement

There is none to be disclosed.

Additional information

Funding

The financial support of the Research Council of the Mashhad Branch, Islamic Azad University and Mashhad University of Medical Sciences are appreciated and acknowledged.