Advanced search
Start date
Betweenand
Related content
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

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

Full text
Author(s):
de Vasconcelos, Debora Naliati [1] ; Ximenes, Valdecir Farias [1]
Total Authors: 2
Affiliation:
[1] Sao Paulo State Univ UNESP, Fac Sci, Dept Chem, BR-17033360 Sao Paulo - Brazil
Total Affiliations: 1
Document type: Journal article
Source: SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY; v. 150, p. 321-330, NOV 5 2015.
Web of Science Citations: 5
Abstract

Congo 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 412 nm and two negative bands at 356 and 490 nm. The use of site I and site II albumin ligands as warfarin and ibuprofen, respectively, provoked different alterations in the Congo red LCD 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 degrees C) was monitored by ICD at 490 nm 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. (c) 2015 Elsevier B.V. All rights reserved. (AU)

FAPESP's process: 13/08784-0 - Kinetic studies of reactions mediated by oxidants produced by neutrophils: mechanism of deleterious action and development of enzyme inhibitors
Grantee:Valdecir Farias Ximenes
Support Opportunities: Regular Research Grants