Structural and dynamic insights of the interaction between tritrpticin and micelles: an NMR study

A large number of antimicrobial peptides (AMPs) acts with high selectivity and specificity through interactions with membrane lipid components. These peptides undergo complex conformational changes in solution; upon binding to an interface, one major conformation is stabilized. Here we describe a st...

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Detalles Bibliográficos
Autores: Talita Lopes dos Santos, Adolfo Henrique de Moraes Silva, Clovis Ryuichi Nakaie, Fabio C. L. Almeida, Shirley Schreier, Ana Paula Canedo Valente
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2016
País:Brasil
Institución:Universidade Federal de Minas Gerais (UFMG)
Repositorio:Repositório Institucional da UFMG
Idioma:inglés
OAI Identifier:oai:repositorio.ufmg.br:1843/45404
Acceso en línea:http://dx.doi.org/10.1016/j.bpj.2016.10.034
http://hdl.handle.net/1843/45404
https://orcid.org/0000-0002-3344-4084
https://orcid.org/0000-0001-7057-1990
https://orcid.org/0000-0001-6046-7006
https://orcid.org/0000-0003-1326-9933
https://orcid.org/0000-0001-7219-1123
Access Level:acceso abierto
Palabra clave:Antimicrobial peptides (AMPs)
Membrane lipid
Cathelicidin AMP
Micelles
Peptides
Tritrpticin (TRP3)
One-dimensional NMR
Two-dimensional NMR
1-lauroyl-2-hydroxy-sn-glycero-3-phosphocholine (LLPC, zwitterionic)
1-myristoyl-2-hydroxy-sn-glycero-3-phospho-1′-rac-glycerol (LMPG, anionic)
Peptídios
Micelas
Produtos de ação antimicrobiana
Espectroscopia de ressonância nuclear
Ressonância magnética nuclear
Descripción
Sumario:A large number of antimicrobial peptides (AMPs) acts with high selectivity and specificity through interactions with membrane lipid components. These peptides undergo complex conformational changes in solution; upon binding to an interface, one major conformation is stabilized. Here we describe a study of the interaction between tritrpticin (TRP3), a cathelicidin AMP, and micelles of different chemical composition. The peptide’s structure and dynamics were examined using one-dimensional and two-dimensional NMR. Our data showed that the interaction occurred by conformational selection and the peptide acquired similar structures in all systems studied, despite differences in detergent headgroup charge or dipole orientation. Fluorescence and paramagnetic relaxation enhancement experiments showed that the peptide is located in the interface region and is slightly more deeply inserted in 1-myristoyl-2-hydroxy-sn-glycero-3-phospho-1′-rac-glycerol (LMPG, anionic) than in 1-lauroyl-2-hydroxy-sn-glycero-3-phosphocholine (LLPC, zwitterionic) micelles. Moreover, the tilt angle of an assumed helical portion of the peptide is similar in both systems. In previous work we proposed that TRP3 acts by a toroidal pore mechanism. In view of the high hydrophobic core exposure, hydration, and curvature presented by micelles, the conformation of TRP3 in these systems could be related to the peptide’s conformation in the toroidal pore.