Deep Metagenomic Sequencing of Cellulolytic Populations Uncovers Novel Taxonomic and Functional Diversity.

Microorganisms drive biogeochemical cycles and because soil is a large global carbon (C) reservoir, soil microorganisms are important players in the global C-cycle. However, many soil microorganisms resist cultivation and soil communities are astoundingly complex and hence the dynamics of soil C metabolism remain incompletely described. Stable isotope probing (SIP) is a useful approach for establishing identity-function connections in microbial communities but has been challenging to employ in soil due to the inadequate resolution of microbial community fingerprinting techniques. High resolution DNA sequencing improves the resolving power of SIP transforming it into a powerful tool for studying the soil C cycle. We conducted a DNA-SIP experiment to track flow of cellulose-C, the most abundant global biopolymer, through a soil microbial community.