A cost-effective 200 kV cryo-EM core facility for high resolution single particle analysis

We sought to establish a sustainable 200 kV cryo-EM core facility for the Northern Rocky Mountain region with high resolution single particle capabilities. With modest funding, relative to 300 kV instruemnts, from the NSF, the Murdock Charitable Trust and Montana State University, we remodeled space and installed a 200 kV Talos Arctica with a Gatan K3 camera, along with supporting software and computational resources. In addition, a refurbished T-12 Spirit was added to support negative stain work, and the instrumentation was collectively organized as a university core facility. The facility is now serving academic and industrial users across the Northern Rocky Mountain region, and beyond. We find that single particle data collection on low symmetry particles greater than 100 kDa routinely gives structures at better than 3 Å resolution, with several high symmetry structures going past 2 Å. These efforts demonstrate that Carnegie R1 - research intensive universities are well served by 200 kV microscopes for single particle work. Such microscopes approach the capabilities of more expensive 300 kV instruments with their ability to produce high resolution single particle structures, and can do so at significant cost savings, contributing to sustainable core facilities.