Insights into the molecular interaction between two polyoxygenated cinnamoylcoumarin derivatives and human serum albumin

Abstract

Ligand binding studies on human serum albumin (HSA) are crucial in determining the pharmacological properties of drug candidates. Here, two representatives of coumarin-chalcone hybrids were selected and their binding mechanism was identified via thermodynamics techniques, curve resolution analysis and computational methods at molecular levels. The binding parameters were derived using spectroscopic approaches and the results point to only one pocket located near the Trp214 residue in subdomain IIA of HSA. The protein tertiary structure was altered during ligand binding and formed an intermediate structure to create stronger ligand binding interactions. The best binding mode of the ligand was initially estimated by docking on an ensemble of HSA crystallographic structures and by molecular dynamics (MD) simulations. Per residue interaction energies were calculated over the MD trajectories as well. Reasonable agreement was found between experimental and theoretical results about the nature of binding, which was dominated by hydrogen bonding and van der Waals contributions.

Interaction of Indole Derivative with Human Serum Albumin: A Combined Spectroscopic and Molecular Dynamics Study

“…On interaction, the polarity around aromatic residues was increased and so the heterocyclic hydrophobic groups of Trp and Tyr residues were exposed to more polar environment. All these observations revealed that the interaction of ID with HSA resulted in conformational changes in HSA …”

“…CD spectrum of HSA exhibited two negative bands in the UV region at 208 and 222 nm respectively. These bands appear due to π→π* and n→π* peptide bond transfer respectively and they signify the characteristic α‐helical structure of HSA …”

Investigation on the interaction of catalase with sodium lauryl sulfonate and the underlying mechanisms

“…ITC experiment was conducted to obtain the quantification of binding affinity and thermodynamic characterization of the binding process . The result of the sequential titrations of SLS into CAT was corrected with the deduction of dilution heats.…”

“…ITC experiment was conducted to obtain the quantification of binding affinity and thermodynamic characterization of the binding process. [34] The result of the sequential titrations of SLS into CAT was corrected with the deduction of dilution heats. The plot in Figure 3 was best fitted to the model of two sets of binding sites, suggesting that two types of binding site existed in CAT upon SLS binding.…”

Insights into the interaction mechanism between tiagabine hydrochloride and two serum albumins

“…The lower panel shows an integrated heat prole that has been appropriately corrected by subtracting the corresponding dilution heats. 22,23 In the lower panel, heat data are plotted against the corresponding molar ratio and tted to a one set of sites model using MicroCal Origin 7.0 soware, which was supplied by the instrument manufacturer. 24 These data can be utilized to calculate the binding constant (K), and the thermodynamics of binding, i.e., enthalpy changes (DH) and entropy changes (DS).…”