The Scheuring-Lab / Bio-AFM-Lab is specialized in Atomic Force Microscopy (AFM) based technologies for the study of various membrane phenomena, such as membrane protein structure, assembly, diffusion and conformational dynamics. Over the past few years, my laboratory has been instrumental in the development and application of High-Speed Atomic Force Microscopy (HS-AFM), unique for the analysis of dynamics of unlabeled single molecules, allowing to bridge structure and function. Using HS-AFM, we reach ~1nm lateral, ~0.1nm vertical and ~100ms temporal resolution. While we continuously push the technological limits, our state-of-the-art HS-AFM can readily resolve dynamics of single domains in transmembrane channels, transporters and membrane associated proteins.
Recent progresses in structural biology (X-ray, cryo-EM) allow now solving membrane protein structures rather routinely. In light of this wealth of structural information, current challenges include the analysis of supramolecular interactions, conformational changes, kinetics of state transitions, pathways of state transitions and physical properties of proteins at work. HS-AFM features several unique strengths to study such phenomena at the single molecule level: It provides concomitant real-space structural and real-time dynamical information, and it operates in a physiological environment, at ambient temperature and pressure and in buffer solution (where membrane proteins are embedded in membranes).
To make HS-AFM more powerful for biological applications, we developed environmental control, i.e. slow and fast buffer exchange, temperature and force control. We further developed novel AFM-based modalities, by integrating optical microscopy into a HS-AFM, and by developing high-speed force spectroscopy (HS-FS) and high frequency microrheology (HF-µR). We also developed HS-AFM line scanning (HS-AFM-LS) and HS-AFM height spectroscopy (HS-AFM-HS) which allows to probe molecular dynamics experimentally at millisecond and microsecond temporal resolution. Most recently, we introduced localization atomic force microscopy (LAFM) a super-resolution method that allows the extraction of quasi-atomic structural details from single molecule AFM data.
Taking advantage of these possibilities, we have made significant contributions in the membrane trafficking and the channels & transporters fields.