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Invasion of Human Cells by a Bacterial Pathogen
Published on: March 21, 2011
Interaction of gentamicin polycation with model and cell membranes
Eugenia Kovács1, Tudor Savopol, Maria-Minodora Iordache
1Carol Davila Medical and Pharmaceutical University, Biophysics and Cellular Biotechnology Department, Bucharest, Romania.
Bioelectrochemistry (Amsterdam, Netherlands)
|April 24, 2012
Summary
Gentamicin, a positively-charged antibiotic, alters cell membrane hydration and fluidity. This interaction may explain how gentamicin permeates living cell membranes via transmembrane channels.
Area of Science:
- Membrane Biophysics
- Cell Biology
- Pharmacology
Background:
- The antibiotic gentamicin is positively charged.
- Understanding its interaction with cell membranes is crucial for explaining its cellular uptake.
- Eukaryotic cell membranes possess complex lipid compositions and charge distributions.
Purpose of the Study:
- To investigate the effects of gentamicin on the organization and biophysical properties of cell membranes.
- To determine if gentamicin induces changes in membrane hydration and fluidity.
- To explore potential mechanisms for gentamicin permeation into living cells.
Main Methods:
- Utilized opossum kidney (OK) epithelial cells as a model for eukaryotic cells.
- Employed laurdan fluorescence spectroscopy and fluorescence anisotropy with TMA-DPH labeled cells.
- Investigated artificial lipid bilayers (liposomes) composed of DMPC and cardiolipin to mimic cell membranes.
Main Results:
- Gentamicin treatment altered membrane hydration and fluidity in OK cells.
- In artificial membranes with negative lipids (cardiolipin), gentamicin increased generalized polarization (GP).
- Conversely, in living OK cells, gentamicin decreased GP, indicating altered membrane organization.
Conclusions:
- Gentamicin's interaction with cell membranes significantly impacts their biophysical properties.
- The differential effects on artificial versus living cell membranes suggest complex interactions.
- Findings propose that membrane organization changes induced by gentamicin may facilitate its passage through cellular channels.
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