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Updated: Jul 16, 2026
11:55
Membrane Transport Processes Analyzed by a Highly Parallel Nanopore Chip System at Single Protein Resolution
Published on: August 16, 2016
Ion transport across transmembrane pores
Hari Leontiadou1, Alan E Mark, Siewert-Jan Marrink
1Groningen Biomolecular Sciences and Biotechnology Institute, Zernike Institute for Advanced Materials, University of Groningen, Nijenborgh 4 9747 AG, Groningen, The Netherlands.
Biophysical Journal
|March 27, 2007
Summary
Molecular dynamics simulations reveal that ions destabilize lipid membrane pores, but mechanical stress can stabilize them. Ion transport through these pores depends on pore size, with larger pores enhancing anion flux.
Area of Science:
- Biophysics
- Computational Chemistry
Background:
- Lipid membranes control ion transport.
- Understanding pore-mediated transport is crucial for cellular function.
Purpose of the Study:
- Investigate ion transport through lipid membrane pores.
- Analyze the effect of ions and mechanical stress on pore stability and ion flux.
Main Methods:
- Molecular dynamics simulations of dipalmitoyl-phosphatidyl-choline bilayers.
- Simulations included preformed water pores with sodium and chloride ions.
Main Results:
- Ions, particularly sodium cations, reduce pore stability by increasing line tension.
- Mechanical stress counteracts ion-induced pore destabilization.
- Ion flux is size-dependent: small pores (<1.5 nm) show slow, similar Na+ and Cl- permeation.
- Larger pores (>1.5 nm) exhibit significantly enhanced anion flux.
Conclusions:
- Pore size critically influences ion transport mechanisms across lipid membranes.
- A model for basal ion permeability is proposed based on pore-mediated transport dynamics.
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