COLL 6 |
| Wah Chiu, National Center for Macromolecular Imaging, National Center for Macromolecular Imaging, Baylor College of Medicine, Houston, TX 77030 |
| Electron cryomicroscopy can resolve three-dimensional structures of large macromolecular assemblies at sub-nanometer resolution (6.5 – 9.5 Å). At this resolution, we can clearly identify long helices and recognize beta sheets. We have applied this imaging tool to a variety of specimens including in vivo ordered actin bundle, spherical viruses and multi-subunit complex. Their molecular mass ranges from 0.5 to hundreds of MDa. In some instances, we can derive the domain folds of protein subunits and observe conformational changes of subunits at different chemical and functional states. This structural informatics cannot be obtained by conventional x-ray crystallography or NMR spectroscopy for these large macromolecular assemblies. This structural approach will become more and more important when the biologists are pursuing the study of large complexes with multiple components in the proteomic era. We will demonstrate this approach with biological examples and discuss the prospect of extending the methodology to near atomic resolution. Acknowledgement: This research has been supported by the NCRR. |
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Bio-Colloids
8:30 AM-11:30 AM, Sunday, March 28, 2004 Marriott -- Grand Ballroom J, Oral
Division of Colloid and Surface Chemistry |