Steven G. Boxer, Professor, Department of Chemistry, Stanford University (US), is our next guest speaker. He will give talks on “Reactions, dynamics and imaging in model biological membranes” (UNIGE, March 19, 2018) and on “Electric fields and enzyme catalysis” (EPFL, March 20, 2018).
About the talks
Reactions, dynamics and imaging in model biological membranes
Supported lipid bilayers provide an excellent platform for the development of advanced imaging and analysis methods. S. Boxer’s lab has prepared DNA-lipid conjugates to create a variety of more complex membrane architectures. These architectures and conjugates are used to simulate membrane fusion, recently extended to enveloped viruses where DNA-lipids serve as surrogate receptors. Imaging mass spectrometry is used to image and quantify the composition and lateral organization of membrane domains with sub-100 nm resolution. Recently, this has been used to probe the nm (1-3 nm) proximity of lipid species.
Electric fields and enzyme catalysis
S. Boxer’s lab has developed the vibrational Stark effect to probe electrostatics in proteins where they can report on functionally important electric fields. In a model enzyme, their work correlates the field sensed at the bond involved in enzymatic catalysis with the activation energy of the reaction it catalyzes, including variations in a series of mutants and variants using non-canonical amino acids. This provides the first direct connection between electric fields and function and can be used to re-interpret results already in the literature and provide a framework for parsing the electrostatic contribution to catalysis.
About the speaker
Steven Boxer is the Camille Dreyfus Professor in the Department of Chemistry at Stanford University. His research interests are in biophysics: the interface of physical chemistry, biology and engineering. Topics of current interest include: electrostatics and dynamics in proteins, especially related to enzyme catalysis; excited state dynamics of green fluorescent protein, especially split GFP, with applications in biotechnology; electron and energy transfer mechanisms in photosynthesis; and the fabrication of artificial systems to simulate, manipulate and image biological membranes. He has served on the scientific advisory board of many start-ups in the general area of biotechnology, and as an advisor to government and non-profit organizations in the US and around the world. He is the recipient of several awards and is an elected Fellow of the American Academy of Arts and Sciences, the Biophysical Society and the National Academy of Sciences.