X-ray studies on phospholipid bilayers. XIII. Interactions with gentamicin

Area of Science:

• Biophysics
• Materials Science
• Pharmacology

Background:

• Aminoglycoside antibiotics like gentamicin (GENT) are crucial in treating bacterial infections.
• Understanding GENT's interaction with biological membranes is vital for drug delivery and toxicity studies.
• Phospholipid bilayers serve as model systems for cell membranes.

Purpose of the Study:

• To investigate the structural perturbations induced by gentamicin on phospholipid bilayers.
• To compare the effects of GENT on different phospholipid types (DMPC and DMPE).
• To evaluate the influence of the surrounding medium (hydrophobic vs. hydrophilic) on GENT-phospholipid interactions.

Main Methods:

• Utilized multi-bilayer systems composed of dimyristoylphosphatidylcholine (DMPC) and dimyristoylphosphatidylethanolamine (DMPE).
• Exposed phospholipid systems to gentamicin (GENT) in both hydrophobic and hydrophilic environments.
• Employed X-ray diffraction techniques to quantify structural changes in the phospholipid bilayers.

Main Results:

• Gentamicin induced significant structural perturbations in dimyristoylphosphatidylcholine (DMPC) bilayers within a hydrophobic medium.
• The extent of perturbation was maximal when GENT interacted with DMPC in the hydrophobic environment.
• Gentamicin in aqueous solutions showed minimal to no significant structural impact on the studied phospholipids (DMPC and DMPE).

Conclusions:

• The interaction of gentamicin with phospholipid bilayers is highly dependent on both the lipid composition and the surrounding medium.
• Hydrophobic environments potentiate the structural effects of gentamicin on specific phospholipids like DMPC.
• Gentamicin's membrane-disrupting potential is context-specific, with limited impact in aqueous solutions.