Diel dynamics and physical interactions of phototrophic isolates from a hot spring microbial mat
EMSL Project ID
60171
Abstract
The microbial mats in the hot springs of Yellowstone National Park (YNP) are composed of diverse thermophilic microbial communities that have evolved to optimize sharing and utilization of scarce resources such as nutrients and light. Cyanobacteria are the primary producers and provide community members with resources for their growth. In these extreme environments, unicellular, nitrogen-fixing cyanobacteria (Synechococcus sp.) and filamentous anoxygenic phototrophs (Chloroflexus sp. and Roseiflexus sp.) are abundant and cope with high temperatures, large daily fluctuations in O2, light intensity, and pH. Genome analyses, in situ labeling studies and metabolomics provide a basic model of the dynamic changes in metabolism that occurs over the diel cycle. We hypothesize that Synechococcus sp. and Chloroflexus sp. can form physical interactions that coordinate both metabolic and social interactions within the community. This community is ideally suited to understand the physical, energetic and metabolic integration of the microbial mat community. Hence, we propose a detailed examination of the diel dynamics, spatial organization and species heterogeneity. This is also required for a process-level understanding of microbiome function and for predicting ecosystem impacts on cycling of metabolites and nutrients. We will use established and sequenced laboratory cultures to grow biofilms containing dominant community members and explore the impact of diel cycling on cell morphology, ultrastructure/interactions, and activities. The resources at EMSL will be used to visualize ultrastructure heterogeneity and physical interactions of the biofilm and explore potential attachments formed using cryo-FIB-milling followed by cryo-SEM and cryo-TEM. We will associate the phenotypes at different diel times with changes in cellular metaproteomic profiles. We will leverage recently acquired metagenomic/transcriptomic and single cell datasets (from DOE-JGI) to strengthen these correlations. To our knowledge, such complementary approaches have not been used for the study of co-cultures of major isolates from microbial communities from extreme environments. The BSSD research area of Environmental Microbiome Research is charged with discovering how microbes interact within communities and adapt to environmental perturbations. This is essential for understanding the many bioenergy and environmental processes relevant to DOE. We plan to detail interactions between two major phototrophic organisms of a microbial community and gain insight into their individual behaviors that can inform a larger model of community behavior. Thermophilic phototrophic communities can serve to unveil links between energy production and the living environment. This aligns with two of EMSL’s science areas: “Environmental Transformations and Interactions” and “Functional and Systems Biology” which attempts to harness biochemical pathways that connect gene functions to complex phenotypic responses within microbial communities.
Project Details
Project type
Exploratory Research
Start Date
2021-12-01
End Date
2022-11-11
Status
Closed
Released Data Link
Team
Principal Investigator
Co-Investigator(s)
Team Members