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Unveiling the Three-Step Model for the Interaction of Imidazolium-Based Ionic Liquids on Albumin

[Image: see text] The effect of the ionic liquids (ILs) 1-methyl-3-tetradecylimidazolium chloride ([C(14)MIM][Cl]), 1-dodecyl-3-methylimidazolium chloride ([C(12)MIM][Cl]), and 1-decyl-methylimidazolium chloride ([C(10)MIM][Cl]) on the structure of bovine serum albumin (BSA) was investigated by fluo...

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Autores principales: Raw, Juliana, Franco, Leandro R., de C. Rodrigues, Luiz Fernando, Barbosa, Leandro R. S.
Formato: Online Artículo Texto
Lenguaje:English
Publicado: American Chemical Society 2023
Acceso en línea:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10586182/
https://www.ncbi.nlm.nih.gov/pubmed/37867681
http://dx.doi.org/10.1021/acsomega.3c04188
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author Raw, Juliana
Franco, Leandro R.
de C. Rodrigues, Luiz Fernando
Barbosa, Leandro R. S.
author_facet Raw, Juliana
Franco, Leandro R.
de C. Rodrigues, Luiz Fernando
Barbosa, Leandro R. S.
author_sort Raw, Juliana
collection PubMed
description [Image: see text] The effect of the ionic liquids (ILs) 1-methyl-3-tetradecylimidazolium chloride ([C(14)MIM][Cl]), 1-dodecyl-3-methylimidazolium chloride ([C(12)MIM][Cl]), and 1-decyl-methylimidazolium chloride ([C(10)MIM][Cl]) on the structure of bovine serum albumin (BSA) was investigated by fluorescence spectroscopy, ultraviolet–visible (UV–vis) spectroscopy, small-angle X-ray scattering (SAXS), and molecular dynamics (MD) simulations. Concerning the fluorescence measurements, we observed a blue shift and a fluorescence quenching as the IL concentration increased in the solution. Such behavior was observed for all three studied imidazolium-based ILs, being larger as the number of methylene groups in the alkyl chain increased. UV–vis absorbance measurements indicate that even at relatively small IL/protein ratios, like 1:1 or 1:2, ([C(14)MIM][Cl]) is able to change, at least partially, the sample turbidity. SAXS results agree with the spectroscopic techniques and suggest that the proteins underwent partial unfolding, evidenced by an increase in the radius of gyration (R(g)) of the scattering particle. In the absence and presence of ([C(14)MIM][Cl]) = 3 mM BSA R(g) increases from 29.1 to 45.1 Å, respectively. Together, these results indicate that the interaction of BSA with ILs is divided into three stages: the first stage is characterized by the protein in its native form. It takes place for protein/IL ≤ 1:2, and the interaction is predominantly due to the electrostatic forces provided by the negative charges on the surface of BSA and the cationic polar head of the ILs. In the second stage, higher IL concentrations induce the unfolding of the protein, most likely inducing the unfolding of domains I and III, in such a way that the protein’s secondary structure is kept almost unaltered. In the last stage, IL micelles start to form, and therefore, the interaction with protein reaches a saturation point and free micelles may be formed. We believe that this work provides new information about the interaction of ILs with BSA.
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spelling pubmed-105861822023-10-20 Unveiling the Three-Step Model for the Interaction of Imidazolium-Based Ionic Liquids on Albumin Raw, Juliana Franco, Leandro R. de C. Rodrigues, Luiz Fernando Barbosa, Leandro R. S. ACS Omega [Image: see text] The effect of the ionic liquids (ILs) 1-methyl-3-tetradecylimidazolium chloride ([C(14)MIM][Cl]), 1-dodecyl-3-methylimidazolium chloride ([C(12)MIM][Cl]), and 1-decyl-methylimidazolium chloride ([C(10)MIM][Cl]) on the structure of bovine serum albumin (BSA) was investigated by fluorescence spectroscopy, ultraviolet–visible (UV–vis) spectroscopy, small-angle X-ray scattering (SAXS), and molecular dynamics (MD) simulations. Concerning the fluorescence measurements, we observed a blue shift and a fluorescence quenching as the IL concentration increased in the solution. Such behavior was observed for all three studied imidazolium-based ILs, being larger as the number of methylene groups in the alkyl chain increased. UV–vis absorbance measurements indicate that even at relatively small IL/protein ratios, like 1:1 or 1:2, ([C(14)MIM][Cl]) is able to change, at least partially, the sample turbidity. SAXS results agree with the spectroscopic techniques and suggest that the proteins underwent partial unfolding, evidenced by an increase in the radius of gyration (R(g)) of the scattering particle. In the absence and presence of ([C(14)MIM][Cl]) = 3 mM BSA R(g) increases from 29.1 to 45.1 Å, respectively. Together, these results indicate that the interaction of BSA with ILs is divided into three stages: the first stage is characterized by the protein in its native form. It takes place for protein/IL ≤ 1:2, and the interaction is predominantly due to the electrostatic forces provided by the negative charges on the surface of BSA and the cationic polar head of the ILs. In the second stage, higher IL concentrations induce the unfolding of the protein, most likely inducing the unfolding of domains I and III, in such a way that the protein’s secondary structure is kept almost unaltered. In the last stage, IL micelles start to form, and therefore, the interaction with protein reaches a saturation point and free micelles may be formed. We believe that this work provides new information about the interaction of ILs with BSA. American Chemical Society 2023-10-05 /pmc/articles/PMC10586182/ /pubmed/37867681 http://dx.doi.org/10.1021/acsomega.3c04188 Text en © 2023 The Authors. Published by American Chemical Society https://creativecommons.org/licenses/by-nc-nd/4.0/Permits non-commercial access and re-use, provided that author attribution and integrity are maintained; but does not permit creation of adaptations or other derivative works (https://creativecommons.org/licenses/by-nc-nd/4.0/).
spellingShingle Raw, Juliana
Franco, Leandro R.
de C. Rodrigues, Luiz Fernando
Barbosa, Leandro R. S.
Unveiling the Three-Step Model for the Interaction of Imidazolium-Based Ionic Liquids on Albumin
title Unveiling the Three-Step Model for the Interaction of Imidazolium-Based Ionic Liquids on Albumin
title_full Unveiling the Three-Step Model for the Interaction of Imidazolium-Based Ionic Liquids on Albumin
title_fullStr Unveiling the Three-Step Model for the Interaction of Imidazolium-Based Ionic Liquids on Albumin
title_full_unstemmed Unveiling the Three-Step Model for the Interaction of Imidazolium-Based Ionic Liquids on Albumin
title_short Unveiling the Three-Step Model for the Interaction of Imidazolium-Based Ionic Liquids on Albumin
title_sort unveiling the three-step model for the interaction of imidazolium-based ionic liquids on albumin
url https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10586182/
https://www.ncbi.nlm.nih.gov/pubmed/37867681
http://dx.doi.org/10.1021/acsomega.3c04188
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