High-Throughput Volatilome Fingerprint Using PTR–ToF–MS Shows Species-Specific Patterns in <i>Mortierella</i> and Closely Related Genera

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 <i>Mortierella sensu lato (s.</i><i>l.</i>) 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 <i>Mortierella s.</i><i>l.</i> isolates growing under standardized conditions. Overall, we detected 139 mass peaks in the headspaces of all 13 <i>Mortierella s.</i><i>l.</i> species studied here. Thus, <i>Mortierella</i><i>s.</i><i>l.</i> species generally produce a high number of different VOCs. <i>Mortierella</i> 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 <i>Mortierella s.</i><i>l.</i> species distribution on a global scale.