Publications (3)0 Total impact
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Article: In vitro pore‐forming activity of the lantibiotic nisin
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ABSTRACT: Nisin is a lantibiotic produced by some strains of Lactococcus lactis subsp. lactis. The target for nisin action is the cytoplasmic membrane of Gram-positive bacteria. Nisin dissipates the membrane potential (Ψ) and induces efflux of low-molecular-mass compounds. Evidence has been presented that a Ψ is needed for nisin action. The in vitro action of nisin was studied on liposomes loaded with the fluorophore carboxyfluorescein. Nisin-induced efflux of carboxyfluorescein was observed in the absence of a Ψ from liposomes composed of Escherichia coli lipids or dioleoylgly-cerophosphocholine (Ole2GroPCho) at low nisin/lipid ratios. The initial rate of carboxyfluorescein efflux is dependent on the nisin/lipid ratio and saturates at high ratios. Both Ψ (inside negative) and φ (inside alkaline) enhance the action of nisin, while nisin is more potent at acidic external pH values. Efficient carboxyfluorescein efflux is observed with the zwitterionic phospholipid Ole2GroPCho or mixtures of Ole2GroPCho with dioleoylglycerophosphoethanolamine and neutral glycolipids, while anionic phospholipids are strongly inhibitory. It is concluded that a Ψ is not essential, but that the total protonmotive force stimulates the action of nisin.European Journal of Biochemistry. 02/1993; 212(2):417 - 422. -
Article: Pediocin PA-1, a Bacteriocin from Pediococcus acidilactici PAC1.0, Forms Hydrophilic Pores in the Cytoplasmic Membrane of Target Cells
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ABSTRACT: Pediocin PA-1 is a bacteriocin which is produced by Pediococcus acidilactici PAC1.0. We demonstrate that pediocin PA-1 kills sensitive Pediococcus cells and acts on the cytoplasmic membrane. In contrast to its lack of impact on immune cells, pediocin PA-1 dissipates the transmembrane electrical potential and inhibits amino acid transport in sensitive cells. Pediocin interferes with the uptake of amino acids by cytoplasmic membrane vesicles derived from sensitive cells, while it is less effective with membranes derived from immune cells. In liposomes fused with membrane vesicles derived from both sensitive and immune cells, pediocin PA-1 elicits an efflux of small ions and, at higher concentrations, an efflux of molecules having molecular weights of up to 9,400. Our data suggest that pediocin PA-1 functions in a voltage-independent manner but requires a specific protein in the target membrane. -
Article: In vitro pore-forming activity of the lantibiotic nisin. Role of protonmotive force and lipid composition
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ABSTRACT: Nisin is a lantibiotic produced by some strains of Lactococcus luctis subsp. lactis. The target for nisin action is the cytoplasmic membrane of Gram-positive bacteria. Nisin dissipates the membrane potential (Δψ) and induces efflux of low-molecular-mass compounds. Evidence has been presented that a Δψ is needed for nisin action. The in vitro action of nisin was studied on liposomes loaded with the fluorophore carboxyfluorescein. Nisin-induced efflux of carboxyfluorescein was observed in the absence of a Δψ from liposomes composed of Escherichia coli lipids or dioleoylglycerophosphocholine (Ole2GroPCho) at low nisin/lipid ratios. The initial rate of carboxyfluorescein efflux is dependent on the nisin/lipid ratio and saturates at high ratios. Both Δψ (inside negative) and ΔpH (inside alkaline) enhance the action of nisin, while nisin is more potent at acidic external pH values. Efficient carboxyfluorescein efflux is observed with the zwitterionic phospholipid Ole2GroPCho or mixtures of Ole2GroPCho with dioleoylglycerophosphoethanolamine and neutral glycolipids, while anionic phospholipids are strongly inhibitory. It is concluded that a Δψ is not essential, but that the total protonmotive force stimulates the action of nisin.
Top co-authors
Institutions
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1993
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University of Groningen
- Department of Medical Microbiology
Groningen, Province of Groningen, Netherlands
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