ABSTRACT
Early detection of invasive aspergillosis is absolutely required for efficient therapy of this fungal infection. The identification of fungal volatiles in patient breath can be an alternative for the detection of
Aspergillus fumigatus
that still remains problematic. In this work, we investigated the production of volatile organic compounds (VOCs) by
A. fumigatus
in vitro
, and we show that volatile production depends on the nutritional environment.
A. fumigatus
produces a multiplicity of VOCs, predominantly terpenes and related compounds. The production of sesquiterpenoid compounds was found to be strongly induced by increased iron concentrations and certain drugs, i.e., pravastatin. Terpenes that were always detectable in large amounts were α-pinene, camphene, and limonene, as well as sesquiterpenes, identified as α-bergamotene and β-
trans
-bergamotene. Other substance classes that were found to be present in the volatome, such as 1-octen-3-ol, 3-octanone, and pyrazines, were found only under specific growth conditions. Drugs that interfere with the terpene biosynthesis pathway influenced the composition of the fungal volatome, and most notably, a block of sesquiterpene biosynthesis by the bisphosphonate alendronate fundamentally changed the VOC composition. Using deletion mutants, we also show that a terpene cyclase and a putative kaurene synthase are essential for the synthesis of volatile terpenes by
A. fumigatus
. The present analysis of
in vitro
volatile production by
A. fumigatus
suggests that VOCs may be used in the diagnosis of infections caused by this fungus.
Volatile and semi-volatile terpenes impact leaf flammability: differences according to the level of terpene identification
