In this project, the investigator combines field research and bioinformatics to describe and quantify Prochlorococcus mixotrophy in different cultured ecotypes as well as uncultivated populations and incorporate this into a global ecosystem model.
In order to understand and accurately predict the complex relationships between climate and the carbon cycle, climate models must account for the critical role of the microbes that mediate significant carbon reservoirs in the ocean. Current models do not reflect the important ecological or functional richness of marine microbial communities. One important marine bacterium that should be included in these models is the marine phototrophic cyanobacterium Prochlorococcus. It is the most abundant oxygenic phototroph in the world's tropical and subtropical oligotrophic oceans and is responsible for a sizable fraction of marine carbon fixation in these areas. This project will examine in detail one aspect of how this organism contributes to carbon cycling, through organic carbon uptake, which is more generally referred to as mixotrophy in phototrophic bacteria. This important process is poorly understood, and has not been incorporated into marine ecosystem and biogeochemistry models that describe carbon flow, even though it has been shown to be prevalent among certain marine phototrophs, especially Prochlorococcus.
The broader impacts include educational activities for undergraduates and K-12 students. Through the MIT summer research program for minority undergraduates, the investigator will develop programming and statistics curricula and work in the laboratory as a mentor to these students. Through the Edgerton Center's programs for K-12 education, the investigator will teach students about the importance of marine ecosystems in maintaining a healthy climate and what is being done to understand it better. In addition, research results will contribute to a better understanding of the future climate by providing an oceanic ecosystem model that includes an important process that has not previously been modeled, cyanobacterial mixotrophy.
This project is supported under the NSF Ocean Sciences Postdoctoral Research Fellowship (OCE PRF) program, with goals to support novel research by early career scientists and increase the diversity of the U.S. ocean sciences workforce and research community. With OCE-PRF support, this project will enable a promising early career researcher to establish themselves in an independent research career related to ocean sciences and broaden participation of under-represented groups in the ocean sciences.
