Anna Seelig-Löffler joined the Biozentrum of the University of Basel in 1972 during her Thesis in Biophysical Chemistry under the guidance of Prof. Gerhard Schwarz. As a postdoctoral fellow she worked with her husband Joachim Seelig.
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Together they investigated the order and dynamics of lipid membranes in the absence and presence of transmembrane proteins by means of solid-state NMR. With her own group she now investigates ATP Binding Cassette (ABC) transporters using different biochemical and physical-chemical techniques. She established an assay that allows the ATPase activity of ABC transporters to be measured in live cells, using the extracellular acidification rate as a proxy. Moreover, she developed an in silico model to predict drug uptake across membranes protected by ABC efflux transporters. For her work on membrane proteins and ABC transporter-substrate interactions she received the STK Award of the Swiss Society for Thermal Analysis and Calorimetry in 2008.