By combining the power of yeast genetics and the sensitivity of biophysical analysis, we are studying function of endogenous yeast membrane proteins (ion channels, cotransporter, ion pumps and water channels) in plasma membrane and tonoplast. For that we developed (adopted to yeast) and successfully applied methods – mainly patch-clamp – for recording electrical charge translocation on the level of individual transport proteins (ion channels), as well as on the macroscopic level, i.e. mediated by a whole population of transporters.
More recently, we established protocols in yeast for analysing transmembrane transport of uncharged substrates, such as water or gases (CO2, NH3). These methods use stopped-flow techniques in combination with light scattering/fluorescence spectroscopy and are intended to study (and understand) important steps in osmoregulation in yeast.
Besides our major interest in yeast membrane transport itself, we are using yeast as a heterologous expression system for functional identification and characterization of membrane transport proteins of plant and animal origin.