Paradoxical lipid dependence of pores formed by the Escherichia coli α-hemolysin in planar phospholipid bilayer membranes

α-Hemolysin (HlyA) is an extracellular protein toxin (117 kDa) secreted by <i>Escherichia coli</i> that targets the plasma membranes of eukaryotic cells. We studied the interaction of this toxin with membranes using planar phospholipid bilayers. For all lipid mixtures tested, addition of...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Bakás, Laura Susana, Chanturiya, Alexandr, Herlax, Vanesa Silvana, Zimmerberg, Joshua
Formato: Articulo
Lenguaje:Inglés
Publicado: 2006
Materias:
Ciencias Exactas
Escherichia coli
Planar Phospholipid Bilayer Membranes
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/83200
Aporte de:
SEDICI (UNLP) de Universidad Nacional de La Plata
id I19-R120-10915-83200
record_format dspace
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Inglés
topic Ciencias Exactas
Escherichia coli
Planar Phospholipid Bilayer Membranes
spellingShingle Ciencias Exactas
Escherichia coli
Planar Phospholipid Bilayer Membranes
Bakás, Laura Susana
Chanturiya, Alexandr
Herlax, Vanesa Silvana
Zimmerberg, Joshua
Paradoxical lipid dependence of pores formed by the Escherichia coli α-hemolysin in planar phospholipid bilayer membranes
topic_facet Ciencias Exactas
Escherichia coli
Planar Phospholipid Bilayer Membranes
description α-Hemolysin (HlyA) is an extracellular protein toxin (117 kDa) secreted by <i>Escherichia coli</i> that targets the plasma membranes of eukaryotic cells. We studied the interaction of this toxin with membranes using planar phospholipid bilayers. For all lipid mixtures tested, addition of nanomolar concentrations of toxin resulted in an increase of membrane conductance and a decrease in membrane stability. HlyA decreased membrane lifetime up to three orders of magnitude in a voltage-dependent manner. Using a theory for lipidic pore formation, we analyzed these data to quantify how HlyA diminished the line tension of the membrane (i.e., the energy required to form the edge of a new pore). However, in contrast to the expectation that adding the positive curvature agent lysophosphatidylcholine would synergistically lower line tension, its addition significantly stabilized HlyA-treated membranes. HlyA also appeared to thicken bilayers to which it was added. We discuss these results in terms of models for proteolipidic pores.
format Articulo
Articulo
author Bakás, Laura Susana
Chanturiya, Alexandr
Herlax, Vanesa Silvana
Zimmerberg, Joshua
author_facet Bakás, Laura Susana
Chanturiya, Alexandr
Herlax, Vanesa Silvana
Zimmerberg, Joshua
author_sort Bakás, Laura Susana
title Paradoxical lipid dependence of pores formed by the Escherichia coli α-hemolysin in planar phospholipid bilayer membranes
title_short Paradoxical lipid dependence of pores formed by the Escherichia coli α-hemolysin in planar phospholipid bilayer membranes
title_full Paradoxical lipid dependence of pores formed by the Escherichia coli α-hemolysin in planar phospholipid bilayer membranes
title_fullStr Paradoxical lipid dependence of pores formed by the Escherichia coli α-hemolysin in planar phospholipid bilayer membranes
title_full_unstemmed Paradoxical lipid dependence of pores formed by the Escherichia coli α-hemolysin in planar phospholipid bilayer membranes
title_sort paradoxical lipid dependence of pores formed by the escherichia coli α-hemolysin in planar phospholipid bilayer membranes
publishDate 2006
url http://sedici.unlp.edu.ar/handle/10915/83200
work_keys_str_mv AT bakaslaurasusana paradoxicallipiddependenceofporesformedbytheescherichiacoliahemolysininplanarphospholipidbilayermembranes
AT chanturiyaalexandr paradoxicallipiddependenceofporesformedbytheescherichiacoliahemolysininplanarphospholipidbilayermembranes
AT herlaxvanesasilvana paradoxicallipiddependenceofporesformedbytheescherichiacoliahemolysininplanarphospholipidbilayermembranes
AT zimmerbergjoshua paradoxicallipiddependenceofporesformedbytheescherichiacoliahemolysininplanarphospholipidbilayermembranes
bdutipo_str Repositorios
_version_ 1764820488381530112

Ejemplares similares