Ph.D. 2008, Michigan State University
The fatty acids attached to lipids (oils, fats, membrane lipids) are the most energy-dense form of biological carbon storage. Plant storage lipids (e.g. vegetable oils) supply humans with much of the calories and nutritionally important fatty acids required in our diet. Membrane lipids are an essential part of all life, and the dynamics of membrane lipid metabolism is key to understanding cellular function. Plant oils also represent a renewable carbon source that can replace petroleum as feedstocks for the chemical industry (for polymers, lubricants, soaps, etc.) or as bio-fuels. However, not all plant oils are alike and the usefulness of each for food, chemicals or fuels depends on the composition of the fatty acids within the oil. All plants produce at least five “common” fatty acids, but there are over 450 “unusual” fatty acid structures characterized in the plant kingdom which represent a large repertoire of valuable chemicals for potential use by humans. A long-term goal of my lab is to understand the control of fatty acid flux through the overlapping metabolic pathways of essential membrane lipid synthesis and accumulation of storage lipids with diverse fatty acid compositions.
My lab uses a variety of biochemical, genetic, and molecular biology approaches to investigate plant lipid metabolism. One key approach is the use of radioisotopic tracers to measure lipid metabolic flux in vivo for discovery of novel metabolic pathways, and elucidate bottlenecks within plant lipid engineering. When combined with genetic and molecular biology approaches, lipid flux analysis allows us to elucidate the genes/enzymes that are essential for controlling the flux of fatty acids into desired end products. To understand both membrane lipid and storage lipid metabolism our research involves a variety of plant tissues (e.g. developing seeds or leaves), and a variety of experimental organisms such as: model plant species (Arabidopsis thaliana, Nicotiana benthamiana); crops (soybean, Camelina sativa, tobacco); and natural plant species that produce industrially useful unusual fatty acids (Physaria fendleri, castor bean). By elucidating the control of fatty acid flux through lipid metabolism we will be able to understand the complex connections between essential membrane lipid function and accumulation of valuable storage oils, as well as produce designer vegetable oils to meet the nutritional, bio-fuel or industrial demands of the future.