Book of Abstracts: Albany 2009
June 16-20 2009
© Adenine Press (2008)
Electron Cryo-microscopy of Molecular Nanomachines and Cells
Electron cryomicroscopy (cryo-EM) is an emerging biophysical tool that can be used to determine structures of molecular nanomachines in fully solvated conformations at subnanometer resolutions (<1 nm). Such cryo-EM maps can reveal long α-helices and large β-sheets. In the highest resolution cryo-EM density maps, it is possible to see side- chains and trace the Cα backbone of protein subunits within a multi-component nanomachine. Electron cryo-tomography (cryo-ET) is equally powerful because of the unique cellular context in which it can capture and reveal cellular nanomachines. Despite reaching only 4-10 nm resolution, cryo-ET reconstructions are capable of imaging whole cells and distinguishing their molecular components. Both of these methods are complementary to conventional methods of structure determination, including X-ray crystallography and NMR spectroscopy. Hybrid methods that combine these structural techniques with cryo-EM and cryo-ET result in a complete view of nanomachines from atomic detail to their spatial and temporal location within a cell. I will describe the experimental and computational pipeline in cryo-EM and cryo-ET and illustrate their effectiveness with biological examples. Research has been supported by grants from NIH and NSF.
National Ctr for Macromolecular Imaging