Cryo–electron microscopy images of protein structures, like this one showing an experimental prototype of a universal flu vaccine, could get even sharper with a new technique that uses ultra cold liquid helium to cool samples. Image Credit: NIH/IMAGE POINT FR/BSIP/Universal Images Group via Getty Images
Technology United KingdomSharper Than Ever: Protein Imaging Gets a Major Upgrade
Researchers have achieved the sharpest image of proteins yet by reviving and upgrading a 20-year-old freezing technique. This sets the stage for imaging even smaller proteins with unprecedented clarity.
The resolution improvement “will feed into getting better detail of bigger protein complexes and smaller protein components within these complexes,” explains Elspeth Garman, a structural biologist at the United Kingdom’s University of Oxford.
The team enhanced a helium-cooled electron microscope by replacing its copper stage with gold to better conduct electrons and reduce charge buildup. They also shrank the holes in the stage to just 100 nanometers, minimizing ice volume and stabilizing samples for sharper focus. This refined cryogenic electron microscopy technique fires electron beams at frozen protein samples to map atomic structures. Cooling proteins to 77 kelvins with liquid nitrogen slashes radiation damage fivefold, dramatically boosting resolution.
