Membrane activity of two short Trp-rich amphipathic peptides.
Biochim Biophys Acta Biomembr
; 1862(7): 183280, 2020 07 01.
Article
em En
| MEDLINE
| ID: mdl-32220553
ABSTRACT
Short linear antimicrobial peptides are attractive templates for developing new antibiotics. Here, it is described a study of the interaction between two short Trp-rich peptides, horine and verine-L, and model membranes. Isothermal titration calorimetry studies showed that the affinity of these peptides towards large unilamellar vesicles (LUV) having a lipid composition mimicking the lipid composition of S. aureus membranes is ca. 30-fold higher than that towards E. coli mimetics. The former interaction is driven by enthalpy and entropy, while the latter case is driven by entropy, suggesting differences in the forces that play a role in the binding to the two types of model membranes. Upon membrane binding the peptides acquired different conformations according to circular dichroism (CD) studies; however, in both cases CD studies indicated stacked W-residues. Peptide-induced membrane permeabilization, lipid flip-flop, molecular packing at the membrane-water interface, and lateral lipid segregation were observed in all cases. However, the extent of these peptide-induced changes on membrane properties was always higher in S. aureus than E. coli mimetics. Both peptides seem to act via a similar mechanism of membrane permeabilization of S. aureus membrane mimetics, while their mechanisms seem to differ in the case of E. coli. This may be the result of differences in both the peptides´ structure and the membrane lipid composition between both types of bacteria.
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Texto completo:
1
Coleções:
01-internacional
Contexto em Saúde:
3_ND
Base de dados:
MEDLINE
Assunto principal:
Peptídeos Catiônicos Antimicrobianos
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Bicamadas Lipídicas
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Lipídeos de Membrana
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Conformação Molecular
Limite:
Humans
Idioma:
En
Revista:
Biochim Biophys Acta Biomembr
Ano de publicação:
2020
Tipo de documento:
Article