The role of water and structure on the generation of reactive oxygen species in peptide/hypericin complexes

Autor(es)

Souza, Marcia I. ^[1] ; Silva, Emerson R. ^[1] ; Jaques, Ygor M. ^[1] ; Ferreira, Fabio F. ^[1] ; Fileti, Eudes E. ^[2] ; Alves, Wendel A. ^[1]

Afiliação do(s) autor(es)

^[1] Univ Fed ABC, Ctr Ciencias Nat & Humanas, BR-09210170 Santo Andre, SP - Brazil

^[2] Univ Fed Sao Paulo, Inst Ciencia & Tecnol, BR-12231280 Sao Jose Dos Campos, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: JOURNAL OF PEPTIDE SCIENCE; v. 20, n. 7, SI, p. 554-562, JUL 2014.
• Citações Web of Science: 16

Resumo

Hybrid associates formed between peptide assemblies and fluorophores are attractive mainly because of their unique properties for biomedical applications. Recently, we demonstrated that the production of reactive oxygen species (ROS) by hypericin and their stability in excited states are enhanced upon conjugation with l,l-diphenylalanine microtubes (FF-MNTs). Although the detailed mechanisms responsible for improving the photophysical properties of ROS remain unclear, tentative hypotheses have suggested that the driving force is the growth of overall dipolar moments ascribed either to coupling between aligned H2O dipoles within the ordered structures or to the organization of hypericin molecules on peptide interfaces. To provide new insights on ROS activity in hypericin/FF-MNTs hybrids and further explore the role of water in this respect, we present results obtained from investigations on the behavior of these complexes organized into different crystalline arrangements. Specifically, we monitored and compared the photophysical performance of hypericin bound to FF-MNTs with peptides organized in both hexagonal (water-rich) and orthorhombic (water-free) symmetries. From a theoretical perspective, we present the results of new molecular dynamics simulations that highlight the distinct hypericin/peptide interaction at the interface of FF-MNTs for the different symmetries. As a conclusion, we propose that although water enhances photophysical properties, the organization induced by peptide structures and the availability of a hydrophobic environment surrounding the hypericin/peptide interface are paramount to optimizing ROS generation. The findings presented here provide useful basic research insights for designing peptide/fluorophore complexes with outstanding technological potential. Copyright (c) 2014 European Peptide Society and John Wiley \& Sons, Ltd. (AU)

• Processo FAPESP: 08/10537-3 - Estudo de polimorfos de fármacos cristalinos através da difração de raios X por policristais e do método de Rietveld
• Beneficiário: Fabio Furlan Ferreira
• Linha de fomento: Auxílio à Pesquisa - Apoio a Jovens Pesquisadores
• Processo FAPESP: 08/53576-9 - Síntese, caracterização e estudo das propriedades eletrônicas dos nanotubos de peptídeos e óxido de titânio
• Beneficiário: Wendel Andrade Alves
• Linha de fomento: Auxílio à Pesquisa - Apoio a Jovens Pesquisadores
• Processo FAPESP: 13/12997-0 - Auto-organização hierárquica de peptídeos anfifílicos: mecanismos fundamentais e potenciais aplicações
• Beneficiário: Wendel Andrade Alves
• Linha de fomento: Auxílio à Pesquisa - Regular
• Processo FAPESP: 08/57805-2 - Instituto de Bioanalítica
• Beneficiário: Lauro Tatsuo Kubota
• Linha de fomento: Auxílio à Pesquisa - Temático
• Processo FAPESP: 13/12674-6 - Investigações estruturais em sistemas-modelo à base de peptídeos anfifílicos
• Beneficiário: Emerson Rodrigo da Silva
• Linha de fomento: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 13/17193-6 - 1st International Conference on peptide materials for biomedicine and nanotechnology (PepMat 2013)
• Beneficiário: Wendel Andrade Alves
• Linha de fomento: Auxílio à Pesquisa - Reunião - Exterior