Environmental Science and Engineering Seminar

Wednesday March 4, 2015 4:00 PM

Multi-dimensional interactions define dynamics in natural microbial communities

Speaker: Karsten Zengler, Department of Systems Biology Research, UC San Diego
Location: South Mudd 365

Microorganisms form diverse communities that have a profound impact on the environment and on human health. These associations are critical to the global carbon cycle and are particularly important in oxygen-limited environments such as wetlands and sediments, but also in parts of the human microbiome. Microbial communities often contain multiple members with complementing and seemingly redundant metabolic capabilities. An understanding of the communal impacts of these redundant metabolic capabilities is currently lacking. We developed a novel genome-scale, multi-omics based modeling approach to investigate the systems biology of syntrophic microbial partnerships to shed new light on a poorly understood aspect of carbon cycle processes. By investigating natural methanogenic populations, we identified the interspecies interactions that define composition and dynamics within syntrophic communities. Species-specific genomes were extracted from metagenomic data using differential coverage binning. Subsequently, we used metabolic modeling leveraging metatranscriptomic information to reveal and quantify a complex intertwined system of metabolic relationships. Furthermore, our results show that auxotrophies create additional interdependencies that define community composition and control carbon and energy flux through the system. Strategic usage of antimicrobials by community members further reinforces this intricate interspecies network, thereby enforcing strong collaboration among community members.

Series Environmental Science and Engineering Seminar

Contact: Kathy Young at 626-395-8732 katyoung@gps.caltech.edu