Developing Quantitative Understanding of Marine Microbiology Using Nutrient Colimitation Observations in Escherichia coli

Marine microbes are integral to biogeochemical cycling. In turn, micro- and macro- nutrients are known to limit their spatial distribution, growth yields, and growth rates. Previous research on nutrient limitation states that the lowest relative bio-necessary nutrient required for growth, is the main limiter of primary production. However, both laboratory and field experiments show unexpected deviations, suggesting that multiple nutrients can limit growth (colimitation). This implies that different nutrient limitations are not mutually exclusive. Despite these observations, research is lacking on how multiple nutrients simultaneously affect growth rates and cellular mechanisms. I present proteomic biomarkers from the model organism Escherichia coli reflecting the cellular biology in carbon and nitrogen colimitation. I will use these preliminary biomarkers to determine the (co)limitation state for microbes at the San Pedro Ocean Time Series, a proxy for the oligotrophic ocean local to Los Angeles. At this location, we push the lower limits of high quality metaproteomic volumes, and I present on the ability of smaller sample volumes to represent microbial communities, despite environmental heterogeneity. Developing a quantitative understanding of microbial interactions with environmental nutrient concentrations will deepen our understanding of microbial thinking and increase our ability to predict microbial responses to changing environmental conditions.

Presentation Preference: Oral

Primary Presenter: Mia Franks, University of Southern California (mgfranks@usc.edu)

Authors:

Mia Franks, University of Southern California  (mgfranks@usc.edu)

Rachael Peng, University of Southern California  (rlpeng@usc.edu)

Michael Manhart, Rutgers University  (mmanhart@rutgers.edu)

Noelle Held, University of Southern California  (nheld@usc.edu)