Multi-omics Illuminates Soil Microbiome Response to Climate Change.

Soil represents one of the most complex ecosystems on Earth, with a high microbial diversity and structural heterogeneity.  Therefore, it has been challenging to study the functional roles of microbial populations within the soil habitat. Recently, the application of omics technologies have been used to explore soil microbial communities and have begun to reveal hitherto unknown soil microbial populations and to link them to specific soil biogeochemical processes. Examples of research areas include study of the impact of altered rainfall patterns on soils of the Great Prairie of the United States and study of the impact of climate warming on Arctic soil microbial communities. For these projects we employed an omics pipeline that includes 16S rRNA gene sequencing, metagenomics, metatranscriptomics and metaproteomics to determine the phylogenetic and functional gene compositions and their expression in complex, non-sterile soil samples collected from the field. These studies have presented several challenges due to the unprecedented large size of the datasets and the insufficiency of available bioinformatic tools & databases to analyze, correlate and integrate the data. To address these challenges we developed a novel functional gene database and used different assembly and analysis algorithms to determine key features in the datasets. The data reveal the microbial diversity, composition and functional potential in the different soil systems and how the microbial communities respond to climate change impacts.