Cryo Electron Microscopy / Structural Biology / Single Particle Analysis

Cryo-electron microscopy (cryo-EM) is a very powerful approach to visualize individual biomolecular machines at an unprecedented resolution and to study their working dynamics in native physiological conditions. At the Center for Nanoscale Systems, researchers are using the state-of-the-art, automated, high-throughput cryo-EM platform to study a variety of biomolecular machines that are vital for improving human health and treating diseases, such as viral membrane fusion machines, ion conducting channels, and protein degradation machines.

  • HIV envelope fusion protein structure

    Adapted from 3D cryo-EM reconstruction of the membrane-fusion machines. Image courtesy of Prof. Youdong Mao.

  • CryoEM can study the structures of biomolecules in their native states.

    Near-atomic resolution can be achieved through statistical analysis of 104 – 106 images of individual protein complexes.

Cryo Electron Microscopy Capabilities

At the CNS, researchers can learn to use three tools with CryoEM capabilities:

FEI Tecnai Arctica CryoTEM with Autoloader (TEM-9)

The FEI Artica is a dedicated Cryogenic-Biological TEM designed for structural biologists. The 200kV microscope combines high resolution performance, high-tilt capability, and cryogenic Auto Loader capable of accommodating 12 samples at a time.

Its cryo-based technology and stability permits a full range of semi-automated applications including: 2D electron crystallography, single particle analysis, and cryo electron microscopy, of frozen hydrated suspensions, cell organelles and cells. 

  • CNS Contact: Carolyn Marks
  • Point resolution: .23nm at zero degree tilt 
  • Tilt range +-70degrees with information limit of .34 nm 
  • Auto Loader 12 samples with long term contamination free loading and storage.

FEI Tecnai Cryo-Bio 200KV FEG TEM (TEM-5)

Dedicated Cryogenic-Biological TEM. The 200kV microscope combines high resolution performance, high-tilt capability, specimen protection at liquid nitrogen temperature with a cryo transfer system.

This system includes a Gatan CT3500 single tilt cyrostage and cryotranfer capability, 200KV Schottky FEG, high tilt capability to 65 Degrees, 2 Gatan Sirius CCD cameras, one 2000 x 2000, and one 4000 x 4000 pixel.

  • CNS Contact: Carolyn Marks
  • Point resolution: .24nm at zero degree tilt 
  • Tilt range +-65degrees

 

Cryo-SEM and Cryo-FIB - Zeiss NVision 40 DualBeam FIB (FIB-2)

The Zeiss NVision 40 CrossBeam with Focused Ion Beam (FIB) and high-resolution field emission SEM. 

The NPVE lithography package allows advanced patterning, milling and deposition. An Omniprobe mechanical probe permits the lift-out of TEM specimens. An EDAX energy dispersive x-ray spectrometer allows the user to determine the chemical composition of the specimen. Both heating and cooling (cryo) stages are available for use.