Exploring soil-free microbial cell extracts as a novel approach towards disentangling microbial carbon and energy utilization patterns in soil.

The primary aim of this study was to establish the use of a viable SFCE in calorespirometric determinations of CUE and community-level substrate response. We hypothesize that SFCE may allow for a less biased determination of CUE than intact soil, while at the same time allowing for a reductionist experimental approach towards population-level growth and metabolic responses. Since CUE is central to many models of terrestrial C cycling, alleviating uncertainties in CUE assessment could lead to more precise mechanistic understanding of C sequestration in soils.