What is the main mechanism by which griseofulvin acts?

Griseofulvin primarily acts by inhibiting mitosis through the disruption of spindle formation. This occurs as griseofulvin binds to tubulin, a protein that plays a crucial role in the formation of microtubules, which are essential for proper spindle apparatus function during cell division. By preventing the normal assembly of microtubules, griseofulvin effectively interferes with the organism's ability to undergo mitosis, leading to cell cycle arrest and ultimately the death of the fungal cells.

This mechanism is particularly effective against dermatophytes, the group of fungi that typically cause superficial infections of the skin, hair, and nails. Griseofulvin is often used in treating conditions such as tinea and onychomycosis. Its specific targeting of the fungal cell division process allows for its effectiveness while having comparatively less effect on human cells, as these cells have different mechanisms of mitosis and do not rely on the same structural components as fungi.

In contrast, the other choices involve mechanisms that do not accurately describe griseofulvin's action. Inhibiting DNA synthesis, binding to ergosterol, and inhibiting cell wall synthesis are characteristic of other antifungal agents, such as azoles or ech