Characterization and Biosynthesis of a Rare Fungal Hopane-Type Triterpenoid Glycoside Involved in the Antistress Property of Aspergillus fumigatus.

A rare fungal hopane-type triterpenoid glycoside fumihopaside A was identified by genome mining in combination with HPLC-MS/MS in Aspergillus fumigatus. Combining genetic deletions in A. fumigatus with heterologous reconstitutions in Aspergillus nidulans of the afum gene cluster, we identified one fungal squalene hopane cyclase AfumA charging the cyclization of the hopene skeleton, one cytochrome P450, and one UDP-glycosyltransferase. Bioassays indicated that fumihopaside A plays important roles in protecting A. fumigatus against heat or ultraviolet stress.