High-Throughput Volatilome Fingerprint Using PTR-ToF-MS Shows Species-Specific Patterns in Mortierella and Closely Related Genera

J Fungi (Basel). 2021 Jan 19;7(1):66. doi: 10.3390/jof7010066.

Abstract

In ecology, Volatile Organic Compounds (VOCs) have a high bioactive and signaling potential. VOCs are not only metabolic products, but are also relevant in microbial cross talk and plant interaction. Here, we report the first large-scale VOC study of 13 different species of Mortierella sensu lato (s. l.) isolated from a range of different alpine environments. Proton Transfer Reaction-Time-of-Flight Mass Spectrometry (PTR-ToF-MS) was applied for a rapid, high-throughput and non-invasive VOC fingerprinting of 72 Mortierella s. l. isolates growing under standardized conditions. Overall, we detected 139 mass peaks in the headspaces of all 13 Mortierella s. l. species studied here. Thus, Mortierella s. l. species generally produce a high number of different VOCs. Mortierella species could clearly be discriminated based on their volatilomes, even if only high-concentration mass peaks were considered. The volatilomes were partially phylogenetically conserved. There were no VOCs produced by only one species, but the relative concentrations of VOCs differed between species. From a univariate perspective, we detected mass peaks with distinctively high concentrations in single species. Here, we provide initial evidence that VOCs may provide a competitive advantage and modulate Mortierella s. l. species distribution on a global scale.

Keywords: Entomortierella; Linnemannia; Mortierellomycotina; PTR–ToF–MS; Podila; fungal volatiles; volatilomes.