Physical Chemistry Seminar

Chemistry Seminar Program

Chemistry Gazebo
3pm (please note special time and location)
Monday, March 4th
Professor Mary Kraft
"Insight into the Sphingolipid and Cholesterol Distribution in the Plasma Membrane Acquired with High-Resolution Secondary Ion Mass Spectrometry
3:00pm Chemistry Gazebo
S.G. Mudd Building
Stanford University

This seminar is free and open to the public.  All Stanford University Chemistry Students are encouraged to attend this special event.

About the Seminar:
Mammalian cell function is greatly influenced by the abundance of two plasma membrane species: sphingolipids and cholesterol. Yet, the distributions of sphingolipids and cholesterol within the plasma membrane and the mechanisms responsible for this organization are poorly understood. This talk will focus on the use of high-resolution secondary ion mass spectrometry (SIMS) for chemically imaging the distributions of isotope-labeled lipids in the plasma membranes of intact cells with high (<100 nm) lateral resolution. In this approach, distinct stable isotopes are metabolically incorporated into lipid species of interest, and then the lipidspecific isotope enrichment is mapped with high-resolution SIMS. This approach has allowed us to image the distributions of metabolically incorporated 15N-sphingolipids and 18O-cholesterol in the plasma membranes of fibroblast cells, and assess co-localization between these components. By visualizing the 15N-sphingolipids and 18O-cholesterol distributions after treating cells with various drugs, we show that lipid organization in the plasma membrane is controlled by complex cellular mechanisms.

About the Speaker:
Professor Mary Kraft received a B.S. in Biochemistry from the University of Illinois at Chicago, and a Ph.D. from the Department of Chemistry at the University of Illinois at Urbana-Champaign under the supervision of Prof. Jeffrey Moore. She received an NIH NRSA Kirschstein Postdoctoral Fellowship, and completed postdoctoral studies with Professor Steven Boxer at Stanford University. Mary also received a Burroughs Wellcome Career Award at the Scientific Interface. In 2007, Mary began her academic career as an assistant professor in the Department of Chemical and Biomolecular Engineering at the University of Illinois in Urbana- Champaign. She also is an affiliated member of the Department of Chemistry and the Center for Biophysics and Computational Biology. Her research focuses on characterizing the lipid organization in cellular membranes with high-resolution secondary ion mass spectrometry. Other research efforts include the development of multivariate models of mass spectrometry data for cell identification.

Please Contact Patricia Dwyer at 650-723-4770