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Felisa Wolfe-Simon

Laboratory for Molecular Biogeochemistry and Organic Geochemistry
Department of Earth and Planetary Sciences
Harvard University
20 Oxford St, Cambridge, MA 02138 USA
Tel.: 617-495-8339
E-mail: wolfe at eps dot harvard dot edu
Web site: http://www.ironlisa.com

Felisa Wolfe-Simon is a Post-Doctoral Fellow. Her work investigates how modern microbes regulate their complement of genetic and biochemical information in response to geologically-relevant experimental conditions. This type of inquiry bridges biology, chemistry, and geology. The questions driving Dr. Wolfe-Simon's research include:  

  1. What antioxidants evolved to cope with decreased availability of iron in the presence of increased oxygen?
  2. Did trace metal availability support the dominance of cyanobacteria during a substantial amount of Earth's early history?
  3. How did the redox conditions of the environment, and thus micronutrient availability, help drive the rise of photosynthetic eukaryotes?
  4. Furthermore, why was there a push towards eukaryotic life?  

Dr. Wolfe-Simon completed her undergraduate education at Oberlin College where she began her interest in biogeochemistry and evolution. Her doctoral dissertation focused on the evolution and selection of a particular metalloenzyme family, the superoxide dismutases, which utilize the redox sensitive and thus biogeochemically significant metals Fe, Mn, Cu/Zn, or Ni. Subsequent to finishing her Ph.D. in Oceanography at Rutgers University, Dr. Wolfe-Simon was awarded an NSF Postdoctoral Fellowship to use methods from cell physiology, molecular biology and biochemistry to dive deeper into the Earth Sciences. Through this fellowship, she explored the geologically relevant differences in metal requirements of cyanobacteria and algae at Arizona State University and is currently investigating the evolution of lipid biosynthesis at Harvard University.  

Expression and localization of triterpenoid pathway biosynthetic proteins in Gemmata obscuriglobus and Methylococcus capsulatus. Life and Earth have co-evolved over the past four billion years. Each exerts significant constraints on the other, as profoundly exemplified in the history of the oxygenation of Earth and in the array of metabolic pathways that require molecular oxygen (O2) for their function. Sterol biosynthesis requires O2 and is thus of considerable interest to a wide variety of fields including biochemistry and the geological sciences. The proposed work explores the relationship between the biosynthesis and physiology of terpenoid lipids and the presence of O2. Eukaryotes produce a diversity of sterols that serve many functions in contemporary organisms. Much less is known about the function that sterols may serve in the select few species of Bacteria that make them. Most of these bacteria also make hopanoids, which are related polycyclic terpenoid compounds that would be presumed - based on structure alone - to fulfill the same physiological function. The critical question then arises: why maintain both pathways? To this end, we proposed to overexpress key enzymes and produce antibodies that recognize them. These antibodies will be utilized to identify the subcellular localization and differential regulation of the target proteins, and their products, in Gemmata obscuriglobus and Methylococcus capsulatus. We will use thus immunological methods to examine the physiological fingerprint of sterol and hopanoid biosynthetic enzymes inside bacterial cells. This information could make a significant contribution to our understanding of the driving mechanisms for the radiation of prokaryotic and eukaryotic diversity. Such results will contribute to the goals of the MIT NAI on the emergence of multicellular life.