Fluorescence, aggregation properties and FT-IR microspectroscopy of elastin and collagen fibers

Autor(es)

Vidal, Benedicto de Campos ^[1]

Afiliação do(s) autor(es)

^[1] Univ Estadual Campinas, Inst Biol, Dept Struct & Funct Biol, BR-01308386 Campinas, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: ACTA HISTOCHEMICA; v. 116, n. 8, p. 1359-1366, 2014.
• Citações Web of Science: 8

Resumo

Histological and histochemical observations support the hypothesis that collagen fibers can link to elastic fibers. However, the resulting organization of elastin and collagen type complexes and differences between these materials in terms of macromolecular orientation and frequencies of their chemical vibrational groups have not yet been solved. This study aimed to investigate the macromolecular organization of pure elastin, collagen type I and elastin-collagen complexes using polarized light DIC-microscopy. Additionally, differences and similarities between pure elastin and collagen bundles (CB) were investigated by Fourier transform-infrared (FT-IR) microspectroscopy. Although elastin exhibited a faint birefringence, the elastin-collagen complex aggregates formed in solution exhibited a deep birefringence and formation of an ordered-supramolecular complex typical of collagen chiral structure. The FT-IR study revealed elastin and CB peptide N-H groups involved in different types of H-bonding. More energy is absorbed in the vibrational transitions corresponding to -CH,-CH2 and CH3 groups (probably associated with the hydrophobicity demonstrated by 8-anilino-1-naphtalene sulfonic acid sodium salt {[}ANS] fluorescence), and to nu CN, delta NH and omega CH2 groups of elastin compared to CB. It is assumed that the a-helix contribution to the pure elastin amide I profile is 46.8%, whereas that of the B-sheet is 20% and that unordered structures contribute to the remaining percentage. An FT-IR profile library reveals that the elastin signature within the 1360-1189 cm(-1) spectral range resembles that of Conex-Toray aramid fibers. (C) 2014 Elsevier GmbH. All rights reserved. (AU)

• Processo FAPESP: 03/04597-0 - Ordem molecular e organização supramolecular em feixes de colágeno: diferenças com a funcionalidade, como suposto efeito de expressão de patogenia, e contribuição metodológica
• Beneficiário: Benedicto de Campos Vidal
• Modalidade de apoio: Auxílio à Pesquisa - Regular