
The scientists who received the 2017 Nobel Prize in chemistry were honored for their development of a technique called cryo-electron microscopy, or cryo-EM. The technology was revolutionary because it enabled scientists to see the atomic structure of biological molecules in high resolution. But cryo-EM still had a catch: It was only effective for imaging large molecules. Now, UCLA biochemists, working with pharmaceutical industry scientists, have developed a solution that will make it possible for cryo-EM to acquire high-quality images of smaller protein molecules also. The scientists engineered a 20-nanometer, cube-shaped protein structure, called a scaffold, with rigid tripod-like protrusions that hold the small proteins in place. The scaffold can be digitally removed from the picture when the imaging is being processed, leaving a composite 3D image of just the small protein scientists are analyzing.