| Texto completo | |
| Autor(es): |
Vicente, Eduardo F.
[1]
;
Basso, Luis Guilherme M.
[2]
;
Cespedes, Graziely F.
[1]
;
Lorenzon, Esteban N.
[1]
;
Castro, Mariana S.
[3]
;
Mendes-Giannini, Maria Jose S.
[4]
;
Jose Costa-Filho, Antonio
[5]
;
Cilli, Eduardo M.
[1]
Número total de Autores: 8
|
| Afiliação do(s) autor(es): | [1] UNESP Univ Estadual Paulista, Inst Quim, Dept Bioquim & Tecnol Quim, Araraquara, SP - Brazil
[2] Univ Sao Paulo, Grp Biofis Mol Sergio Mascarenhas, Inst Fis Sao Carlos, Sao Carlos, SP - Brazil
[3] Univ Brasilia, Brazilian Ctr Prot Res, Dept Cell Biol, Brasilia, DF - Brazil
[4] UNESP Univ Estadual Paulista, Fac Ciencias Farmaceut, Dept Anal Clin, Araraquara, SP - Brazil
[5] Univ Sao Paulo, Dept Fis, Fac Filosofia Ciencias & Letras Ribeirao Preto, BR-14049 Ribeirao Preto, SP - Brazil
Número total de Afiliações: 5
|
| Tipo de documento: | Artigo Científico |
| Fonte: | PLoS One; v. 8, n. 4 APR 9 2013. |
| Citações Web of Science: | 13 |
| Resumo | |
Antimicrobial peptides (AMPs) isolated from several organisms have been receiving much attention due to some specific features that allow them to interact with, bind to, and disrupt cell membranes. The aim of this paper was to study the interactions between a membrane mimetic and the cationic AMP Ctx(Ile(21))-Ha as well as analogues containing the paramagnetic amino acid 2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid (TOAC) incorporated at residue positions n = 0, 2, and 13. Circular dichroism studies showed that the peptides, except for {[}TOAC(13)] Ctx(Ile(21))-Ha, are unstructured in aqueous solution but acquire different amounts of alpha-helical secondary structure in the presence of trifluorethanol and lysophosphocholine micelles. Fluorescence experiments indicated that all peptides were able to interact with LPC micelles. In addition, Ctx(Ile(21))-Ha and {[}TOAC(13)] Ctx(Ile(21))-Ha peptides presented similar water accessibility for the Trp residue located near the N-terminal sequence. Electron spin resonance experiments showed two spectral components for {[}TOAC(0)] Ctx(Ile(21))-Ha, which are most likely due to two membrane-bound peptide conformations. In contrast, TOAC(2) and TOAC(13) derivatives presented a single spectral component corresponding to a strong immobilization of the probe. Thus, our findings allowed the description of the peptide topology in the membrane mimetic, where the N-terminal region is in dynamic equilibrium between an ordered, membrane-bound conformation and a disordered, mobile conformation; position 2 is most likely situated in the lipid polar head group region, and residue 13 is fully inserted into the hydrophobic core of the membrane. (AU) | |
| Processo FAPESP: | 09/10997-7 - Interações com membranas de peptídeos de fusão da glicoproteína s do SARS-CoV |
| Beneficiário: | Luís Guilherme Mansor Basso |
| Modalidade de apoio: | Bolsas no Brasil - Doutorado |
| Processo FAPESP: | 10/17662-8 - Ressonância magnética eletrônica em estudos de estrutura, função e interações de moléculas com interesse biológico |
| Beneficiário: | Antonio José da Costa Filho |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |
| Processo FAPESP: | 10/06526-6 - Uso de peptídeos sintéticos no estudo da proteína DHODH e do peptídeo de fusão do vírus da Dengue. |
| Beneficiário: | Eduardo Maffud Cilli |
| Modalidade de apoio: | Auxílio à Pesquisa - Regular |