Multi-faceted approaches to discovering and predicting microbial nutritional interactions.

Nearly all microbes rely on other species in their environment to provide nutrients they are unable to produce. Nutritional interactions include not only the exchange of carbon and nitrogen compounds, but also amino acids and cofactors. Interactions involving cross-feeding of cobamides, the vitamin B12 family of cofactors, have been developed as a model for nutritional interactions across species and environments. In addition to experimental studies, new developments in culture-independent methodologies such as genomics and modeling now enable the prediction of nutritional interactions in a broad range of organisms including those that cannot be cultured in the laboratory. New insights into the mechanisms and evolution of microbial nutritional interactions are beginning to emerge by combining experimental, genomic, and modeling approaches.