Reshuffling of Aspergillus fumigatus cell wall components chitin and β-glucan under the influence of caspofungin or nikkomycin Z alone or in combination.

Chitin and β-glucan are major cell wall components of Aspergillus spp. We investigated the antifungal activity of chitin synthesis inhibitors nikkomycin Z, polyoxin D, flufenoxuron, lufenuron, and teflubenzuron, alone and combined with the β-glucan synthesis inhibitor caspofungin. Only nikkomycin Z and caspofungin were found to act synergistically. The nikkomycin Z-induced chitin decrease corresponded with a β-glucan increase, while with the caspofungin-induced β-glucan decrease, an increase in chitin was found. This could explain the synergistic activity of this combination of drugs.