The microbiomic metaproteome of the taiga tick <i>Ixodes persulcatus</i> from the Tyumen region

Metagenomic studies have revealed the taxonomic composition of the taiga tick (Ixodes persulca tus) microbiome, whereas metaproteomic data has provided information on the biochemically active fraction of the microbial community residing in the tick. The aim of this study was to characterize the biological pro cesses taking place within the microbiome of the taiga tick I. persulcatus using a metaproteomic approach. To expand the range of identifiable proteins, we used two trypsin concentrations in sample preparation for mass spectrometric analysis. The metaproteomes of unfed female and male ticks were analyzed, which ena bled identification of protein products encoded by 2,100 genes from microorganisms belonging to 203 bacteri al and fungal species. Increased abundance of proteins associated with Ascomycota fungi, particularly abun dant in females, were detected. Proteins from the pathogenic Rickettsia and Borrelia species were identified. These findings enable a transition from a taxonomic metagenomic description to a functional analysis of the microbial consortium role in the physiology of the vector tick, particularly given the identified microbiota differences related to the tick sex.