CAREER: Mlcrobial Lipidomics in Changing Oceans (MILCO)

The response of ocean ecosystems to global environmental change is an important concern for ocean scientists and the public. The proposed research focuses on developing chemical tools to investigate how marine microbes respond and adapt to changes in their surrounding environment, such as increasing temperature, ocean acidification, oxygen loss, and availability of nutrients.

Modifications in the lipids (a.k.a. biomarkers, or fats) present in the cell membranes of all known forms of life allow organisms to cope with environmental stress. The team will use “lipidomics,” an emerging field that involves studying the complete set of lipids produced by a given organism or an entire ecosystem, to understand how microbes can adapt to the global-scale changes in the environment impacting the ocean.

They will do this using mesocosm and microcosm experiments. Mesocosms are large-scale outdoor experimental systems that examine the natural environment under semi-controlled conditions. Microcosms are small-scale indoor experimental systems that allow controlled experimentation of individual organisms or simplified ecosystems with one or more parameters.

These systems offer unparalleled teaching opportunities about the functioning of aquatic ecosystems and their interaction with the physical and chemical environment. In parallel with the research efforts, the CU Boulder team will lead an effort to enhance bilingual (English/Spanish) ocean educational curriculum and activities for school children and teachers, particularly from underprivileged backgrounds, as well as the general public in the landlocked state of Colorado.

Recent advances in lipidomics now allow the use of lipids as indicators of microbial adaptation to environmental change. This CAREER project uses an integrated experimental and educational approach to examine: (a) lipid remodeling in natural microbial communities exposed to multiple environmental stressors tied to varying upwelling intensity, explored through large scale mesocosm experiments; b) lipid remodeling in key phytoplankton groups isolated from upwelling ecosystems, subjected to selected environmental stressors in microcosm and culture experiments; and (c) new bilingual (English/Spanish) educational modules and outreach opportunities that will enhance ocean literacy with the aim of inspiring and empowering citizens to promote the health of our oceans.

The work will test the overarching hypotheses that experimental studies allow the distinction between changes in lipidome caused by varying biological sources (phylogeny) and physiological adaptation (lipid remodeling) of source organisms exposed to changing physical-chemical conditions. Results will illuminate the application of intact polar lipids (IPLs) in observational oceanography for the study of microbial adaptation to future scenarios of global change—something that to date has not been rigorously tested.

In addition, this study will further inform the interpretation of biomarkers preserved in marine sediments as tracers of past microbial and biogeochemical processes. The educational focus will be implemented through the School at Sea that includes: (a) development of educational modules (Microcosm-in-a-Mason-jar and Mesocosm-in-my-backyard experiments) for students in grades 5-8 that will be tested in local schools and then disseminated in stablished education and outreach programs at CU Boulder; (b) promotion of ocean literacy among high school students as well as minority and community college undergraduate students; (c) training of the next generation of science educators and volunteers (Sea Rangers) in activities that will promote ocean literacy.

Furthermore, results from this study will serve as the basis for curriculum development for undergraduate courses in global change and organic geochemistry. Key partnerships with CU’s Museum of Natural History through the Girls At the Museum Exploring Science (GAMES) program, Science Discovery Program, and CIRES’s Education and Outreach Office, as well as the Inland Ocean Coalition will provide platforms for the dissemination of School at Sea to a broader audience of students and the general public.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.