A novel metabolic monitoring system identified nutrition-mediated microbial interactions

"Omics" technologies have been developed to understand the whole complex microbial systems; however, most omics studies reported so far were utilized to analyze the living matters of “single-species”. To understand the cell-cell interaction in the gut microbial complex, we selected to examine the interaction of Escherichia coli O157:H7 (O157) and Bifidobacterium longum (BL), known as a pathogenic and a commensal bacteria, as a first step for understanding the whole gut microbial complex. We have developed a novel time-lapse 2D-NMR metabolic profiling system in order to measure the extracellular metabolites, which are considered a key factor to understand the bacterial crosstalk. Furthermore, in combination with transcriptome and proteome analysis, we found that the relationship between BL and O157 could be partially regarded as the producer and the consumer of nutrients, especially in the case of serine and aspartate metabolism. These findings suggest that our novel profiling systems could be a powerful tool toward understanding crosstalk of the whole microbial complex such as the gut, industrial bioreactors or environmental microbial communities. In vitro mono and coculture were performed. All experiments were performed in duplicate.