NSF Postdoctoral Fellowship in Biology FY 2011

Mackey Katherine R, San Jose CA

Investigators

Abstract

This action funds an NSF Postdoctoral Research Fellowship in Biology for FY 2011, Intersections of Biology and Mathematical and Physical Sciences. The fellowship supports a research and training plan in a host laboratory for the Fellow at the intersection of biology and chemistry. The title of the research and training plan for this fellowship to Katherine Mackey is "Photosynthetic strategies for iron limitation in Earth's most abundant photosynthetic organism." The host institutions for this research are the Marine Biological Laboratory and the Woods Hole Oceanographic Institution with sponsoring scientists Drs. Anton Post and Mak Saito. Photosynthesis is a complex process in which cells use energy from light to grow, and optimizing this process can be difficult when nutrients needed for growth are scarce. In freshwater algae and marine diatoms, numerous strategies have evolved to optimize photosynthesis during iron and nitrogen limitation and are well-studied. However, less is known about the photosynthetic strategies employed by picocyanobacteria to cope with less than optimal levels of iron and nitrogen. These small, single-celled algae are the most abundant photosynthetic organisms on Earth, and their diversity and global ubiquity provide an ideal model system in which to characterize responses to iron and nitrogen limitation, using both wild type and laboratory cultures. This research probes the short-term (acclimation) and long-term (adaptation) responses of picocyanobacteria to iron and nitrogen limitation and determines how these strategies impact iron, nitrogen and carbon cycling in the environment. Training goals include learning cutting-edge methods in global and targeted proteomics, automated gene sequencing, and trace metal analysis, allowing the Fellow to branch into geochemistry. This project offers new insights on photosynthetic strategies in the global distributions of photosynthetic organisms from algae to land plants and on how nutrient stress drives the evolution of photosynthesis in nature. Broader impacts include one-on-one mentoring of students in the laboratory and outreach to local schools. A teaching option supports the Fellow to develop a photosynthesis course for the Partnership Education Program for minority students at WHOI and other institutions.