Drivers of Lipid Remodeling in Marine Microbial Communities

It is known that microbes can remodel the chemistry of their cell membrane lipids (lipidome) in response to environmental stress (lipid remodeling). Yet, the utility of lipids in oceanographic studies has been limited by the number of known chemical structures and biological sources, as well as by bioinformatic limitations for the processing of large environmental data sets. This presentation will examine lipid remodeling in natural microbial communities of the Humboldt upwelling system exposed to multiple environmental stressors in both observational and experimental (mesocosm) studies. I will test the overarching hypothesis that we can distinguish between changes in the lipidome caused by varying biological sources (phylogeny) and physiological adaptation (lipid remodeling) of source organisms exposed to changing environmental conditions such as nutrient stoichiometries, temperature, pH, and light availability along redox gradients. I will discuss how these results have implications for ocean biogeochemistry under future scenarios of climate change.