On the interaction of Bovine Serum Albumin (BSA) with cethyltrimethyl ammonium chloride surfactant: Electron Paramagnetic Resonance (EPR) study
Autor(a) principal: | |
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Data de Publicação: | 2006 |
Outros Autores: | , |
Tipo de documento: | Artigo |
Idioma: | eng |
Título da fonte: | Brazilian Journal of Physics |
Texto Completo: | http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-97332006000100014 |
Resumo: | Electron paramagnetic resonance (EPR) has been used to monitor the interaction of bovine serum albumin (BSA) with cationic cethyltrimethylammonium chloride (CTAC) at pH 7.0. EPR results using 5-DSA and 16-DSA nitroxide spin labels show that in the presence of BSA the EPR spectra are composed of two label populations, one contacting the protein and a second one due to label localization in the micelles. Evidence is also obtained for a competition of the surfactants with the spin labels for the high affinity binding sites of the stearic acid spin labels as monitored by changes in the fraction of the two label populations as the surfactant concentration is increased. The effect of sodium dodecylsulfate (SDS) reported previously seems to be stronger in the sense that increase in SDS concentration leads to a complete transfer of spin label from close protein contact sites to the micelles while for CTAC, apparently, a significant immobilization of probe remains even at higher surfactant concentrations. EPR gives information on the dynamics inside the protein-surfactant aggregates and associated to label localization and motion. The dynamics of the nitroxide spin-labels bound to the protein correlate to the stronger binding of SDS to BSA as compared to CTAC binding. Simulation of EPR spectra for spin labels in pure CTAC micelles, in pure protein or in protein-bound micelles show rotational correlation times similar to those obtained from the simple evaluation based on the intensities of nitrogen hyperfine coupling components. Rotational correlation times obtained for 5-DSA bound to protein are larger as compared to 16-DSA values suggesting greater mobility for the later even when bound to the protein. |
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On the interaction of Bovine Serum Albumin (BSA) with cethyltrimethyl ammonium chloride surfactant: Electron Paramagnetic Resonance (EPR) studyEPRBovine serumElectron paramagnetic resonance (EPR) has been used to monitor the interaction of bovine serum albumin (BSA) with cationic cethyltrimethylammonium chloride (CTAC) at pH 7.0. EPR results using 5-DSA and 16-DSA nitroxide spin labels show that in the presence of BSA the EPR spectra are composed of two label populations, one contacting the protein and a second one due to label localization in the micelles. Evidence is also obtained for a competition of the surfactants with the spin labels for the high affinity binding sites of the stearic acid spin labels as monitored by changes in the fraction of the two label populations as the surfactant concentration is increased. The effect of sodium dodecylsulfate (SDS) reported previously seems to be stronger in the sense that increase in SDS concentration leads to a complete transfer of spin label from close protein contact sites to the micelles while for CTAC, apparently, a significant immobilization of probe remains even at higher surfactant concentrations. EPR gives information on the dynamics inside the protein-surfactant aggregates and associated to label localization and motion. The dynamics of the nitroxide spin-labels bound to the protein correlate to the stronger binding of SDS to BSA as compared to CTAC binding. Simulation of EPR spectra for spin labels in pure CTAC micelles, in pure protein or in protein-bound micelles show rotational correlation times similar to those obtained from the simple evaluation based on the intensities of nitrogen hyperfine coupling components. Rotational correlation times obtained for 5-DSA bound to protein are larger as compared to 16-DSA values suggesting greater mobility for the later even when bound to the protein.Sociedade Brasileira de Física2006-03-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-97332006000100014Brazilian Journal of Physics v.36 n.1a 2006reponame:Brazilian Journal of Physicsinstname:Sociedade Brasileira de Física (SBF)instacron:SBF10.1590/S0103-97332006000100014info:eu-repo/semantics/openAccessTabak,MarcelSousa Neto,Diógenes deSalmon,Carlos Ernesto Garridoeng2006-04-03T00:00:00Zoai:scielo:S0103-97332006000100014Revistahttp://www.sbfisica.org.br/v1/home/index.php/pt/ONGhttps://old.scielo.br/oai/scielo-oai.phpsbfisica@sbfisica.org.br||sbfisica@sbfisica.org.br1678-44480103-9733opendoar:2006-04-03T00:00Brazilian Journal of Physics - Sociedade Brasileira de Física (SBF)false |
dc.title.none.fl_str_mv |
On the interaction of Bovine Serum Albumin (BSA) with cethyltrimethyl ammonium chloride surfactant: Electron Paramagnetic Resonance (EPR) study |
title |
On the interaction of Bovine Serum Albumin (BSA) with cethyltrimethyl ammonium chloride surfactant: Electron Paramagnetic Resonance (EPR) study |
spellingShingle |
On the interaction of Bovine Serum Albumin (BSA) with cethyltrimethyl ammonium chloride surfactant: Electron Paramagnetic Resonance (EPR) study Tabak,Marcel EPR Bovine serum |
title_short |
On the interaction of Bovine Serum Albumin (BSA) with cethyltrimethyl ammonium chloride surfactant: Electron Paramagnetic Resonance (EPR) study |
title_full |
On the interaction of Bovine Serum Albumin (BSA) with cethyltrimethyl ammonium chloride surfactant: Electron Paramagnetic Resonance (EPR) study |
title_fullStr |
On the interaction of Bovine Serum Albumin (BSA) with cethyltrimethyl ammonium chloride surfactant: Electron Paramagnetic Resonance (EPR) study |
title_full_unstemmed |
On the interaction of Bovine Serum Albumin (BSA) with cethyltrimethyl ammonium chloride surfactant: Electron Paramagnetic Resonance (EPR) study |
title_sort |
On the interaction of Bovine Serum Albumin (BSA) with cethyltrimethyl ammonium chloride surfactant: Electron Paramagnetic Resonance (EPR) study |
author |
Tabak,Marcel |
author_facet |
Tabak,Marcel Sousa Neto,Diógenes de Salmon,Carlos Ernesto Garrido |
author_role |
author |
author2 |
Sousa Neto,Diógenes de Salmon,Carlos Ernesto Garrido |
author2_role |
author author |
dc.contributor.author.fl_str_mv |
Tabak,Marcel Sousa Neto,Diógenes de Salmon,Carlos Ernesto Garrido |
dc.subject.por.fl_str_mv |
EPR Bovine serum |
topic |
EPR Bovine serum |
description |
Electron paramagnetic resonance (EPR) has been used to monitor the interaction of bovine serum albumin (BSA) with cationic cethyltrimethylammonium chloride (CTAC) at pH 7.0. EPR results using 5-DSA and 16-DSA nitroxide spin labels show that in the presence of BSA the EPR spectra are composed of two label populations, one contacting the protein and a second one due to label localization in the micelles. Evidence is also obtained for a competition of the surfactants with the spin labels for the high affinity binding sites of the stearic acid spin labels as monitored by changes in the fraction of the two label populations as the surfactant concentration is increased. The effect of sodium dodecylsulfate (SDS) reported previously seems to be stronger in the sense that increase in SDS concentration leads to a complete transfer of spin label from close protein contact sites to the micelles while for CTAC, apparently, a significant immobilization of probe remains even at higher surfactant concentrations. EPR gives information on the dynamics inside the protein-surfactant aggregates and associated to label localization and motion. The dynamics of the nitroxide spin-labels bound to the protein correlate to the stronger binding of SDS to BSA as compared to CTAC binding. Simulation of EPR spectra for spin labels in pure CTAC micelles, in pure protein or in protein-bound micelles show rotational correlation times similar to those obtained from the simple evaluation based on the intensities of nitrogen hyperfine coupling components. Rotational correlation times obtained for 5-DSA bound to protein are larger as compared to 16-DSA values suggesting greater mobility for the later even when bound to the protein. |
publishDate |
2006 |
dc.date.none.fl_str_mv |
2006-03-01 |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/article |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
format |
article |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-97332006000100014 |
url |
http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-97332006000100014 |
dc.language.iso.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
10.1590/S0103-97332006000100014 |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
text/html |
dc.publisher.none.fl_str_mv |
Sociedade Brasileira de Física |
publisher.none.fl_str_mv |
Sociedade Brasileira de Física |
dc.source.none.fl_str_mv |
Brazilian Journal of Physics v.36 n.1a 2006 reponame:Brazilian Journal of Physics instname:Sociedade Brasileira de Física (SBF) instacron:SBF |
instname_str |
Sociedade Brasileira de Física (SBF) |
instacron_str |
SBF |
institution |
SBF |
reponame_str |
Brazilian Journal of Physics |
collection |
Brazilian Journal of Physics |
repository.name.fl_str_mv |
Brazilian Journal of Physics - Sociedade Brasileira de Física (SBF) |
repository.mail.fl_str_mv |
sbfisica@sbfisica.org.br||sbfisica@sbfisica.org.br |
_version_ |
1754734862640611328 |