Fusion of small unilamellar vesicles with viable EDTA-treated Escherichia coli cells

Marvin, H.J.P.; Beest, Martin B.A. ter; Hoekstra, Dick

doi:10.1128/jb.171.10.5268-5275.1989

Cited by 10 publications

(3 citation statements)

References 32 publications

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“…It has been extensively discussed that the known higher sensitivity of these LPS mutant strains to various hydrophobic drugs is due to lateral phase segregation phenomena and the formation of stable phospholipid domains in the outer layer of the OM, which allow the hydrophobic molecules to penetrate (Takeuchi and Nikaido, 1981;Vaara and Vaara, 1983b;Nikaido, 1990). To influence the permeation properties of the OM, divalent cations and polycationic molecules like, e.g., Ca 2ϩ , high-molecular-weight poly-(L-lysine), and polymyxin nonapeptide (PMBN) have been used as membrane-active substances (Jones and Osborn, 1977;Vaara and Vaara, 1983a;Marvin et al, 1989). The treatment of smooth (wild-type) strains of Gram-negative bacteria with polycations causes the release of 20 -30% LPS from the OM and, at the same time, drastically increases its permeability to hydrophobic antibiotics (Vaara and Vaara, 1983b).…”

Section: Introductionmentioning

confidence: 99%

The Influence of Poly-(l-Lysine) and Porin on the Domain Structure of Mixed Vesicles Composed of Lipopolysaccharide and Phospholipid: An Infrared Spectroscopic Study

Schultz

Naumann

1998

Biophysical Journal

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Fourier transform infrared (FTIR) spectroscopy has been used to study the thermotropic phase behavior of binary lipid mixtures composed of deuterated phospholipids (PLs) and lipopolysaccharides (LPSs). Furthermore, the influence of an extrinsic high-molecular, polycationic polypeptide (poly-(L-lysine), PLL(500)) and an intrinsic membrane protein (outer membrane protein F, OmpF) on these binary mixtures was investigated by FTIR spectroscopy. "Deep rough" mutant LPS (ReLPS), isolated from Salmonella minnesota R595, and perdeuterated 1,2-dimyristoylphosphatidylethanolamine (DMPEd54) were used as model lipids. Deuteration of one of the lipids permitted the detection of lipid protein interaction with each lipid component separately. For this purpose, the symmetric >CH2 and >CD2 stretching bands were utilized as specific monitors to scrutinize the state of order of the membranes. From the individual phase transition temperatures Tm and the shape of the phase transition profiles, it is established that ReLPS and DMPEd54 are molecularly immiscible. In addition to the two domains of the pure lipid components, a third, domain-like structure is detected that may coexist with these pure domains. This domain-like structure undergoes a gel to liquid-crystalline L1 (beta <--> alpha) phase transition at temperatures distinctly different from that of the respective pure lipid domains. The nature of this type of domain is discussed in terms of a "border region" model that adequately explains the experimentally observed complex phase transition profiles. It is further demonstrated that the extrinsic polycationic polypeptide PLL(500) and the intrinsic, pore-forming protein OmpF isolated from Escherichia coli interact preferentially and highly specifically with the negatively charged ReLPS. Both the synthetic polypeptide and the pore-forming protein increased the tendency of ReLPS and DMPEd54 to segregate into distinct, well-separated domains. Whereas the transition profiles of the ternary system ReLPS/DMPEd54/PLL(500) showed the features of a phase segregation phenomenon not affecting the transition temperatures of the pure lipid components, the ternary system composed of ReLPS/DMPEd54 and OmpF exhibited phase transition curves that were characterized by an unspecific (DMPEd54/OmpF) and a strong and unique (ReLPS/OmpF) type of lipid-protein interaction. Furthermore, semiquantitative estimations supported the supposition that OmpF might be able to induce bilayer asymmetry in preformed symmetrical ReLPS/DMPEd54 vesicles.

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Section: Introductionmentioning

confidence: 99%

The Influence of Poly-(l-Lysine) and Porin on the Domain Structure of Mixed Vesicles Composed of Lipopolysaccharide and Phospholipid: An Infrared Spectroscopic Study

Schultz

Naumann

1998

Biophysical Journal

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“…In this case two LPS-covered membrane surfaces come into contact and fuse. Small unilamellar phospholipid vesicles are also able to fuse with the surface of gram-negative bacteria but only after the cells have been treated with EDTA (33). Lipid bilayer patches in the OM and bacterial OM proteins seem to be involved in this type of fusion.…”

mentioning

confidence: 97%

Penetration of Enveloped Double-Stranded RNA Bacteriophages φ13 and φ6 intoPseudomonas syringaeCells

Daugelavičius

Cvirkaite

Gaidelyte

et al. 2005

J Virol

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Bacteriophages 6 and 13 are related enveloped double-stranded RNA viruses that infect gram-negative Pseudomonas syringae cells. 6 uses a pilus as a receptor, and 13 attaches to the host lipopolysaccharide. We compared the entry-related events of these two viruses, including receptor binding, envelope fusion, peptidoglycan penetration, and passage through the plasma membrane. The infection-related events are dependent on the multiplicity of infection in the case of 13 but not with 6. A temporal increase of host outer membrane permeability to lipophilic ions was observed from 1.5 to 4 min postinfection in both virus infections. This enhanced permeability period coincided with the fast dilution of octadecyl rhodamine B-labeled virus-associated lipid molecules. This result is in agreement with membrane fusion, and the presence of temporal virus-derived membrane patches on the outer membrane. Similar to 6, 13 contains a thermosensitive lytic enzyme involved in peptidoglycan penetration. The phage entry also caused a limited depolarization of the plasma membrane. Inhibition of host respiration considerably decreased the efficiency of irreversible virus binding and membrane fusion. An active role of cell energy metabolism in restoring the infection-induced defects in the cell envelope was also observed.

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“…Molecular mechanisms to explain the loss of the membrane barrier are based upon the disruption of bacterial lipopolysaccharide (25,31,32), as reviewed by Vaara (43), but these explanations remain speculative. Various reports employing similar techniques have been used to fuse artificial vesicles to bacterial cells (29) or to introduce molecules that normally cannot permeate the cells (10,11). The procedure devised was such that loss of cell viability and inhibition of the capacity of the C5b-8 complex to support C9-mediated killing was minimized.…”

mentioning

confidence: 99%

C9-mediated killing of bacterial cells by transferred C5b-8 complexes: transferred C5b-9 complexes are nonbactericidal

Blanchard

Dankert

1994

Infect Immun

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The formation of the CSb-9 complex on the outer membrane of complement-sensitive cells ofEscherichia coli results in inhibition of inner membrane function and the death of the cell. Cells bearing a precursor of the C5b-9 site, the C5b-8 complex, suffer no loss in viability. Antibiotic-sensitive, complement-sensitive donor cells bearing precursor C5b-8 complexes were incubated with equal numbers of antibiotic-resistant, complementsensitive acceptor cells that had not been exposed to a complement source. This cell mixture was incubated with 5 mM EDTA for 5 min and then with calcium chloride (20 mM) for various times. The excess calcium ion concentration was effectively reduced with additional EDTA, and the cell mixture was washed and resuspended in buffer. The viability of the acceptor cells was assayed by plating on antibiotic-containing media. C9 was added to the mixture, and the mixture was incubated for 10 min at 3rC and then plated as described above.It was found that the acceptor cells were killed by the addition of purified C9 only after incubation with donor cells bearing C5b-8 sites during the transfer procedure. This indicates that precursor CSb-8 sites that support C9-mediated killing could be transferred between cells. No loss in viability was detected for acceptor cells subjected to the procedure described above in the presence of donor cells bearing complete C5b-9 complexes, formed prior to mixing with acceptor cells for the transfer procedure.

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Fusion of small unilamellar vesicles with viable EDTA-treated Escherichia coli cells

Cited by 10 publications

References 32 publications

The Influence of Poly-(l-Lysine) and Porin on the Domain Structure of Mixed Vesicles Composed of Lipopolysaccharide and Phospholipid: An Infrared Spectroscopic Study

The Influence of Poly-(l-Lysine) and Porin on the Domain Structure of Mixed Vesicles Composed of Lipopolysaccharide and Phospholipid: An Infrared Spectroscopic Study

Penetration of Enveloped Double-Stranded RNA Bacteriophages φ13 and φ6 intoPseudomonas syringaeCells

C9-mediated killing of bacterial cells by transferred C5b-8 complexes: transferred C5b-9 complexes are nonbactericidal

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