Membrane transport proteins – channels and energy-coupled pumps – are the molecular gatekeepers of the cell.  For microbes afloat in a hostile environment, these proteins import vital nutrients and export dangerous toxins.  My lab is currently focused on understanding the export of F- anion, an inhibitor of glycolysis and protein synthesis that bacteria, archaea, unicellular eukaryotes, and plants have confronted in their environmental milieu over evolutionary time.

Specific F- export isn’t an easy task since the ion’s radius only differs by half an Angstrom from that of the world’s most abundant aqueous ion, Cl-.   Two different membrane protein families have evolved to accomplish it: the Fluc family of fluoride channels, and the CLCF family of F-/H+ antiporters. My laboratory is investigating the molecular mechanism of both classes of protein, using a breadth of biochemical and biophysical techniques, including electrophysiology, membrane protein biochemistry, x-ray crystallography, and macromolecular NMR.



Crystal structure of Fluc channel with F- ions bound