What is the significance of squalene epoxidase inhibition by terbinafine?

The significance of squalene epoxidase inhibition by terbinafine relates directly to the drug's action on the fungal cell membrane. Squalene epoxidase is an enzyme in the ergosterol biosynthetic pathway, specifically responsible for converting squalene into lanosterol, a precursor of ergosterol. Ergosterol is a vital component of fungal cell membranes, playing a role similar to cholesterol in human cell membranes.

When terbinafine inhibits squalene epoxidase, the production of ergosterol is significantly reduced. This leads to an accumulation of toxic squalene within the fungal cell and a decrease in the synthesis of ergosterol, resulting in disrupted cell membrane integrity. Without sufficient ergosterol, the cell membrane becomes compromised, which can ultimately lead to cell lysis and death of the fungus.

This mechanism explains why the correct answer focuses on the disruption of fungal cell membrane integrity as a primary outcome of squalene epoxidase inhibition by terbinafine. The other options do not capture the direct impact of this inhibition on the fungal cell, making them less relevant to the specific action of terbinafine.