New paper explores how algal exometabolites shape surrounding bacterial communities

Northen Lab researchers Vanessa Brisson, Suzanne Kosina, and Trent Northen co-authored the publication “Dynamic Phaeodactylum tricornutum exometabolites shape surrounding bacterial communities”. While the role algal exometabolites play in regulating microbial community composition is not fully understood, this paper identifies algal exudates from the model diatom Phaeodactylum tricornutum and demonstrates their ability to influence bacterial isolate growth and surrounding bacterial populations. The phycosphere microbial community composition was found to vary when cultured alone in artificial seawater, together with P. tricornutum, or with the addition of algal exometabolites; however, the exact mechanisms driving these changes are unclear. 

To understand which algal metabolites might be impacting community composition, the Northen Metabolomics Lab profiled both the intracellular and extracellular metabolites of P. tricornutum  using LC-MS/MS. We found subsets of metabolites that were specific to extra and intracellular compartments, 12 of which were used to supplement phycosphere isolate cultures to evaluate impacts on growth. Two of these were further tested and shown to drive additional changes to community composition. While other factors are suggested to play a role in influencing microbiome composition, these preliminary findings help us to understand how metabolite-mediated interactions shape the structure and function of microbial communities.

Phaeodactylum tricornutum exometabolites

Image: Phaeodactylum tricornutum metabolite production across growth phases.

To learn more about the development of this platform, read the full article here.

Brisson, V., Swink, C., Kimbrel, J., Mayali, X., Samo, T., Kosina, S. M., Thelen, M., Northen, T. R., Stuart, R. K. (2023) Dynamic Phaeodactylum tricornutum exometabolites shape surrounding bacterial communities. New Phytologist. https://doi.org/10.1111/nph.19051