Graduate Program Affiliations
- BISI-Physiological Systems (PSYS)
- BISI-Molecular & Cellular Biology (MOCB)
- Chemistry and Biochemistry
I have a long-standing research interest in the molecular basis for the function of membrane channels, including voltage gating and selectivity. Past research focused mainly on channels formed in the mitochondrial outer membrane. These channels are: 1) VDAC, a 30kDa channel that controls the flow of metabolites across the outer membrane; 2) ceramide channels, large, protein permeable, channels formed by the self-assembly of a lipid, ceramide. I also have considerable interest in the cell physiology of these channels: how VDAC regulates mitochondrial function and the role of both of these in controlling the initiation of apoptosis. The research is mechanistic in nature and we use a variety of techniques from electrophysiological recordings to electron microscopy.
The main current research focus is on a novel channel-former from E. coli which we named Triplin. This three-channel unit resembles in some ways the extensively studied porins located in the bacterial outer membrane. However, it displays steep voltage-dependence much like the channels responsible for electrical excitability in mammalian neurons and muscles. Moreover, the 3 channels are highly cooperative in a rather unique way making triplin perhaps the most complex channel-former described to date. The goals are to understand how this molecular machine functions and to determine its role in bacterial physiology.
- Meller Basic Medical Research Award, 1976
- College of Chemical and Life Sciences Faculty Award for Excellence in Research, 1995
- Chair of the Bioenergetics Subgroup of the Biophysical Society 2004-07
- On the Council of the Biophysical Society, 2008-12
- Fellow of the AAAS, 2013
- H index is 66
- B.Sc., Honors in Chemistry and Biochemistry, McGill University, 1970
- Ph.D., McGill University, 1974, Structure and mode of action of membrane transport systems; molecular basis for voltage control of channel-forming proteins.