Novel virocell metabolic potential revealed in agricultural soils by virus-enriched soil metagenome analysis

Viruses are now recognized as important players in microbial dynamics and biogeochemical cycles in the oceans. Yet, compared with aquatic ecosystems, virus discovery in terrestrial ecosystems has been challenging partly due to the inherent complexity of soils. To expand our understanding of soil viruses and their putative contributions to soil microbial processes, we analysed metagenomes of community-level virus-enriched suspensions by tangential flow filtration obtained from two French agricultural soils. We found viral sequences representing a total of 239 viral operational taxonomic units that corresponded to 29.5% of the mapping reads in the metagenomic datasets. The analysis of their genomic sequences revealed novel virocell metabolic potential with implications to virus-host interactions, carbon cycling, plant-beneficial functions in the rhizosphere, horizontal gene transfer and other relevant microbial strategies applied to survive in soils.