Investigation of the morphological changes and molecular function of cells, membranes and proteins by single molecule sensing AFM
Sprache des Vortragstitels:
8th Biophysics Workshop (XBW 2013)
Sprache des Tagungstitel:
Atomic Force Microscopy (AFM) has developed to an important tool in life sciences. It allows determining the surface roughness of soft biological samples like cells and membranes at near physiological conditions, label-free, and with a lateral resolution in the nanometer range.
In addition, upgrading the usually inert AFM tip by tethering biological molecules to the tip allows gaining more information. Topography and Recognition Imaging (TREC) combines tapping mode imaging with a biosensing AFM tip and allows to simultaneously map the surface topography as well as to localize specific binding partners. A second technique, also based on the use of molecular sensing bio-functionalized AFM tips, is Molecular Recognition Force Spectroscopy (MRFS). There a biosensing tip is repeatedly approached and withdrawn from a surface containing the corresponding binding partner of interest. Within every force distance cycle a ligand-receptor complex can be formed followed by forced rupturing. By varying the pulling velocities the complex energy landscape can be explored giving insights into kinetic and energetic aspects of the interaction.