Boreal moss-microbe interactions are revealed through metagenome assembly of novel bacterial species

Abstract

- Moss microbial communities play important roles for ecosystem processes in boreal forests. Host identity and leaf litter presence can affect microbial community structures of mosses. However, the extent to which host-specific characteristics and land use type affect taxonomic and functional profiles of microbial communities of boreal mosses is still poorly understood. - We used shotgun metagenomic sequencing to characterize microbial taxonomy and metabolic KEGG ortholog (KO) profiles between green and brown sections of five moss species across different natural sites, and two moss species between a natural site and a mine site in Eeyou Istchee, Quebec, Canada. - Our results demonstrate that the abundance of nitrogen metabolic genes differ between moss sections and that mosses from natural and mine environment associate with different microbial taxa and KO profiles. Importantly, conditions at the mine site appear to favor microbial taxa that can tolerate perturbated environments, including taxa that can oxidize sulfur and participate in biofilm formation. - Overall, our results highlight that moss section, moss species identity, and land-use type are strong drivers of diversity and community structure of moss-associated microbial taxa and metabolic genes. These findings could have major implications for boreal forests facing climate change and anthropogenic pressures