Acquisition of the Thermo Scientific Glacios transmission electron microscope

University Of Pennsylvania, Philadelphia PA

Investigators

Abstract

Project Summary/Abstract Cryo electron microscopy (cryo-EM) is a powerful technique for understanding the structure and function of complex biochemical systems, with important implications for novel biological insights and therapy. Currently, cryo-EM is routinely used to generate atomic or near-atomic resolution structures of macromolecules in different conformational states, in complexes with regulatory proteins, with small molecule metabolites or pharmacological modulators, and in in their native cellular environment. With this proposal, we are seeking to expend cryo electron microscopy (cryo-EM) imaging capabilities and increase the throughput for cryo-EM sample screening and high- resolution data collection at the Perelman School of Medicine at the University of Pennsylvania (UPenn). Currently, UPenn’s cryo-EM needs are supported by the availability of a Krios G3i microscope that is used for both sample screening and data collection. This existing instrumentation has facilitated a major expansion of single particles cryo-EM and cryo electron tomography (cryo-ET) investigations at UPenn. Because of the tremendous increase in usage of the Krios microscope, we are now running into a significant throughput bottleneck, which significantly impedes timely progress and scientific impact. While this microscope has been used seven days a week and 24 hours a day with the exception of the unavoidable maintenance and repairs, UPenn requests from 7 major users and 3 minor users are now exceeding the available microscope time, and one Krios microscope alone can no longer fully accommodate all current cryo-EM and cryo-ET users at UPenn. The state-of-the-art 200 keV Glacios transmission electron microscope to be acquired will facilitate the needs of major users and minor users at UPenn as it comes with significant improvements in terms of electron optics and stability of the microscope column. Yet, the most valuable feature of the Glacios microscope is that the microscope is equipped with an Autoloader (cryogenic sample manipulation robot) that can load and screen 12 different specimens in one cycle. This feature of the microscope will substantially accelerate the rate of the cryo- EM/cryo-ET sample screening and optimization process. Moreover, the Glacios microscope will offer high- resolution single particle cryo-EM data collection at UPenn and MicroED capabilities of this system will allow us to gain expertise in this technique on campus. The requested Glacios microscope will accelerate discovery in fields as diverse as fundamental cell biology and biochemistry, infectious disease, membrane protein structure, neurobiology, epigenetics, metabolism and cancer. The Glacios microscope requested here will therefore have a significant impact on biomedical research and therapy at UPenn.