Estudos estruturais por RMN do glicopiranosil-triazol-peptídeo [pOAcGlc-trz-A14]PS-2 em meios miméticos de membrana
Ano de defesa: | 2017 |
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Autor(a) principal: | |
Orientador(a): | |
Banca de defesa: | |
Tipo de documento: | Dissertação |
Tipo de acesso: | Acesso aberto |
Idioma: | por |
Instituição de defesa: |
Universidade Federal de Minas Gerais
UFMG |
Programa de Pós-Graduação: |
Não Informado pela instituição
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Departamento: |
Não Informado pela instituição
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País: |
Não Informado pela instituição
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Palavras-chave em Português: | |
Link de acesso: | http://hdl.handle.net/1843/SFSA-AL5N7W |
Resumo: | In this work, structural modifications of the glycosylated derivative of PS-2, [pOAcGlc-trz-A14]PS-2, are investigated and compared in detailed by using circular dichroism (CD) and nuclear magnetic resonance (NMR). Firstly, glucopyranosyl-triazole-peptide [pOAcGlc-trz-A14]PS-2 was performed employing a Fmoc strategy of solid phase synthesis associated with copper (I)-catalyzed azide alkyne cycloaddition reaction. The product was then purified and characterized by high performance liquid chromatography (HPLC) and mass spectrometry (MS). The conformational preferences of [pOAcGlc-trz-A14]PS-2 were investigated by CD in different environment and conditions, such as in the presence of phospholipid vesicles, micelles and in mixtures with different TFE:H2O ratios. The obtained results indicated high degrees of helical structure in the membrane media commonly used for NMR experiments. Thus, NMR spectra were obtained for the compound in TFE-d2: H2O (60:40) and in the presence of DPC-d38 micelles (400 mmol.L-1). The respective correlations were assigned and the information obtained from these analyses were converted into geometric restrictions for structural calculations. Comparative analyses between the obtained three-dimensional structures and the ones of PS-2 in TFE-d2: H2O (60:40), already report in the literature, between the calculated structures of [pOAcGlc-trz-A14]PS-2 in the different environment were performed. The obtained results point to more pronounced differences in the C-terminal portion, in which different orientations of the glycosidic group of the glucopyranosyl-triazole-peptide in the different environment analyzed and aromatic stacking interactions between the H-18 and F-19 residues are observed. |