Quantifying Lipid Mobility and Peptide Binding for Gram-Negative and Gram-Positive Model Supported Lipid Bilayers.
J Phys Chem B
; 123(49): 10433-10440, 2019 12 12.
Article
em En
| MEDLINE
| ID: mdl-31729230
ABSTRACT
Model membranes are a valuable tool to investigate the mechanism of interaction between antibiotic compounds and bacterial membranes. However, the development of supported lipid bilayer (SLB) models for Gram-negative and Gram-positive bacteria has been challenging because of the high charge and spontaneous curvature of the lipids that make up these membranes. Here we describe a method for preparing mimetic Gram-negative inner membrane and Gram-positive membrane SLBs, including asymmetric SLBs (asy-SLBs) that contain a fluorescent tracer only in the upper leaflet of the membrane. We quantified the dynamics of the lipids in these membranes with fluorescence correlation spectroscopy (FCS) and found that lipid diffusion is slower in Gram-negative SLBs/asySLBs than in Gram-positive SLBs/asySLBs. Peptide binding to these membranes was also characterized using colistin, a Gram-negative specific antibiotic. Interactions between colistin and membrane lipids phosphatidylethanolamine (PE) or cardiolipin (TOCL) were probed with pulsed-interleaved excitation fluorescence cross-correlation spectroscopy (PIE-FCCS). Overall, our data provide unique insight into the diffusion dynamics of lipids in Gram-negative and Gram-positive membranes as well as a novel platform for investigating the mechanism of interaction between antibiotic peptides and bacterial membrane lipids.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Peptídeos
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Fosfatidiletanolaminas
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Cardiolipinas
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Bactérias Gram-Negativas
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Bactérias Gram-Positivas
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Bicamadas Lipídicas
Idioma:
En
Revista:
J Phys Chem B
Assunto da revista:
QUIMICA
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Estados Unidos
País de publicação:
EEUU
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ESTADOS UNIDOS
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ESTADOS UNIDOS DA AMERICA
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EUA
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UNITED STATES
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UNITED STATES OF AMERICA
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US
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USA