Spectroscopic and molecular modelling analysis of the interaction between ethane‐1,2‐diyl bis(N,N‐dimethyl‐N‐hexadecylammoniumacetoxy)dichloride and bovine serum albumin

Abstract

Several spectroscopic approaches namely fluorescence, time-resolved fluorescence, UV-visible, and Fourier transform infra-red (FT-IR) spectroscopy were employed to examine the interaction between ethane-1,2-diyl bis(N,N-dimethyl-N-hexadecylammoniumacetoxy)dichloride (16-E2-16) and bovine serum albumin (BSA). Fluorescence studies revealed that 16-E2-16 quenched the BSA fluorescence through a static quenching mechanism, which was further confirmed by UV-visible and time-resolved fluorescence spectroscopy. In addition, the binding constant and the number of binding sites were also calculated. The thermodynamic parameters at different temperatures (298 K, 303 K, 308 K and 313 K) indicated that 16-E2-16 binding to BSA is entropy driven and that the major driving forces are electrostatic interactions. Decrease of the α-helix from 53.90 to 46.20% with an increase in random structure from 22.56 to 30.61% were also observed by FT-IR. Furthermore, the molecular docking results revealed that 16-E2-16 binds predominantly by electrostatic and hydrophobic forces to some residues in the BSA sub-domains IIA and IIIA.

Interaction of cyanidin-3-O-glucoside with three proteins

“…And that for Hb were s 0 = 4.040 ns and s = 3.953 ns while the values were s 0 = 4.110 ns and s = 4.055 ns for Mb. As can be seen, there was no significant change in the fluorescence lifetime when C3G was added to the three proteins, which was indicative of a static quenching mechanism (Patel et al, 2015). The results were consistent with the fluorescence experiment.…”

Effect of triazole‐tryptophan hybrid on the conformation stability of bovine serum albumin

“…Therefore, τ av data was further used for determination of the τ 0/ τ values. The values of τ 0/ τ were found approximately equal to one and clearly suggest the involvement of the static quenching mechanism for the TTH–BSA interaction system which is in good agreement with our steady‐state fluorescence results.…”

Elucidation of the interaction of human serum albumin with anti‐cancer sipholane triterpenoid from the Red Sea sponge

“…HSA contains a single tryptophan at position 214, while 18 tyrosine residues are distributed all along the protein chain . Phenylalanine has a very low quantum yield as compared with other fluorophores . When excited at 280 nm, fluorescence emission is mainly from tryptophan, although the tyrosine residue has the strongest fluorescence intensity.…”

“…UV-visible absorption spectroscopy was applied to investigate HSA complex formation and structural changes upon binding with sipholenone A. HSA has several aromatic amino acids, such as tryptophan, tyrosine and phenylalanine, which absorb at around 280 nm. [24] Any change in the HSA UV spectrum is ascribed to conformational change as a result of complex formation between protein and ligand.…”

“…[20] Phenylalanine has a very low quantum yield as compared with other fluorophores. [24] When excited at 280 nm, fluorescence emission is mainly from tryptophan, although the tyrosine residue has the strongest fluorescence intensity. In the presence of tryptophan in the protein there is an energy transfer from the tyrosine residue to tryptophan and, as a result, the tryptophan showed the highest fluorescence emission.…”