Title
Multi-Spectroscopic and Theoretical Analysis on the Interaction between Human Serum Albumin and a Capsaicin Derivative—RPF101
Author
Otávio Augusto Chaves, Maurício Temotheo Tavares, Micael Rodrigues Cunha, Roberto Parise-Filho, Carlos Maurício R. Sant’Anna, José Carlos Netto-Ferreira
Year
2018
Journal
Biomolecules
Abstract
The interaction between the main carrier of endogenous and exogenous compounds in the human bloodstream (human serum albumin, HSA) and a potential anticancer compound (the capsaicin analogue RPF101) was investigated by spectroscopic techniques (circular dichroism, steady-state, time-resolved, and synchronous fluorescence), zeta potential, and computational method (molecular docking). Steady-state and time-resolved fluorescence experiments indicated an association in the ground state between HSA:RPF101. The interaction is moderate, spontaneous (ΔG° < 0), and entropically driven (ΔS° = 0.573 ± 0.069 kJ/molK). This association does not perturb significantly the potential surface of the protein, as well as the secondary structure of the albumin and the microenvironment around tyrosine and tryptophan residues. Competitive binding studies indicated Sudlow’s site I as the main protein pocket and molecular docking results suggested hydrogen bonding and hydrophobic interactions as the main binding forces.
Full Article
Instrument
J-815
Keywords
Circular dichroism, Secondary structure, Fluorescence, Ligand binding, Chemical stability, Biochemistry