Albumin-induced circular dichroism in Congo red: applications for studies of amyloid-like fibril aggregates and binding sites

dc.contributor.authorVasconcelos, Débora Naliati de [UNESP]
dc.contributor.authorXimenes, Valdecir Farias [UNESP]
dc.contributor.institutionUniversidade Estadual Paulista (Unesp)
dc.date.accessioned2015-12-07T15:40:36Z
dc.date.available2015-12-07T15:40:36Z
dc.date.issued2015-11-05
dc.description.abstractCongo red (CR), one of the most commonly used dyes for the identification of amyloid fibril aggregates, is also a ligand of native bovine serum albumin (BSA). Induced circular dichroism (ICD) is a phenomenon observed when a chiral compound induces chirality in an achiral one. Here, we study the spectral properties and analytical applications of ICD in Congo red provoked by its interaction with BSA. The complex BSA:CR displays a strong ICD spectrum with a positive band at 412nm and two negative bands at 356 and 490nm. The use of site I and site II albumin ligands as warfarin and ibuprofen, respectively, provoked different alterations in the Congo red ICD spectrum. The BSA binding sites were modified by oxidation and the ICD signal was sensitive to this alteration. The thermal treatment of the BSA:CR complex (30-90°C) was monitored by ICD at 490nm and showed a sigmoidal pattern typical of phase transition in proteins. The altered ICD spectrum is consistent with the formation of amyloid-like fibril aggregates in BSA, which was confirmed by thioflavin T and Rayleigh scattering assays. In conclusion, the ICD provoked by the binding of Congo red to albumin may represent a new spectroscopic technique for studying alterations in the structure of albumin regarding its binding sites and the formation of amyloid aggregates.en
dc.description.affiliationUnespUniversidade Estadual Paulista, Departamento de Química, Faculdade de Ciências de Bauru
dc.description.sponsorshipFundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
dc.description.sponsorshipConselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
dc.description.sponsorshipIdFAPESP: 2013/08784-0
dc.format.extent321-330
dc.identifierhttp://dx.doi.org/10.1016/j.saa.2015.05.089
dc.identifier.citationSpectrochimica Acta. Part A, Molecular And Biomolecular Spectroscopy, v. 150, p. 321-330, 2015.
dc.identifier.doi10.1016/j.saa.2015.05.089
dc.identifier.issn1873-3557
dc.identifier.lattes4066413997908572
dc.identifier.pubmed26056983
dc.identifier.urihttp://hdl.handle.net/11449/131688
dc.language.isoeng
dc.publisherElsevier B. V.
dc.relation.ispartofSpectrochimica Acta. Part A, Molecular And Biomolecular Spectroscopy
dc.rights.accessRightsAcesso restrito
dc.sourcePubMed
dc.subjectAlbuminen
dc.subjectAmyloid aggregatesen
dc.subjectBinding sitesen
dc.subjectCongo reden
dc.subjectInduced circular dichroismen
dc.titleAlbumin-induced circular dichroism in Congo red: applications for studies of amyloid-like fibril aggregates and binding sitesen
dc.typeArtigo
dcterms.rightsHolderElsevier B. V.
unesp.author.lattes4066413997908572
unesp.campusUniversidade Estadual Paulista (Unesp), Faculdade de Ciências, Baurupt

Arquivos