Antifungal Agents

Antifungal agents target pathogenic fungi to prevent infections from spreading. For example, amphotericin B is one such agent that targets the fungal cell membrane.

Amphotericin B is an amphipathic molecule, containing both hydrophobic and hydrophilic regions.

The mycosamine and carboxylic acid groups in the hydrophilic region bind to ergosterol, a sterol predominant in the fungal plasma membrane. This binding stabilizes the molecule’s insertion into the lipid bilayer.

Once inserted, multiple amphotericin molecules align themselves with the surrounding lipid chains and assemble into pore-like channels.

These channels allow the uncontrolled leakage of ions, especially potassium, which causes an osmotic imbalance and leads to fungal cell death.

In another mechanism, amphotericin B molecules align parallel to the lipid bilayer.

This orientation sequesters ergosterol toward the membrane surface, disrupting membrane structural integrity.