Dynamic TEM
EMSL Project ID
51142
Abstract
Achieving a holistic, molecular-level understanding of the structure, function and mechanism of cellular machinery remains a formidable scientific challenge. While over 100,000 protein structures have been solved to date, we are only scratching the surface of our understanding. For example, a single species of the grass Brachypodium is believed to express over 25,000 proteins on its own. Furthermore, many proteins across species still remain classified as Protein of Unknown Structure or Protein of Unknown Function including over 25% of the 8,000 genes annotated in the smallest free-living eukaryote. One of the main bottlenecks for determining the function and mechanism of a given protein is the ability to capture structural dynamics and intermediate or transient conformations during its reaction cycle. Unfortunately, there is a major gap in the spatiotemporal landscape for imaging capabilities that can provide experimental data on the angstrom to few nanometer spatial resolution with simultaneous nanosecond to millisecond temporal resolution – scales at which the majority of conformational changes occur within a protein complex. Overcoming this spatiotemporal capability gap would enable unprecedented observation of dynamic physio-chemical processes under natural (or simulated) environmental conditions including visualizing molecular machines from microbial, fungal and plant cells and host-virus interactions; observing redox reactions at mineral surfaces; probing the formation and aging of aerosol particles; and tracking the catalytic breakdown or creation of specific materials and chemical products. In response, we propose to fully develop the Dynamic Transmission Electron Microscope (DTEM) for inclusion with the EMSL User Program by end of FY2020. Specifically, our aims are to: 1) perform the first-ever onsite complete gun modification and optimize pulse brightness and resolution, 2) conduct world-first 100 nanosecond pulsed cryo-EM imaging, and 3) capture pump-probe dynamics in real-time and in near-native environments at the nanometer to near atomic scale with temporal resolution on the microsecond to nanosecond timescale. The development of DTEM has been a multi-year project and we are finally in a self-reliant state with the best chance to commission and apply this instrument to BER relevant science in FY2020.
Project Details
Start Date
2019-12-18
End Date
2021-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members