First 3D single-particle reconstruction of 20S Proteasome at 2.8 Å resolution
Image courtesy of Melody Campbell and the National Resource for Automated Molecular Microscopy, US.

Breaking the 3 Å barrier

The above series of images show a 3D reconstruction of the 20S proteasome at 2.8 Å resolution. On the right, the oxygen atom (red) found in a single water molecule is separated from the surrounding structure by 3.1 and 3.4 Å, respectively. Studying this molecule at high resolution demonstrates that scientists can identify water molecules and hydrogen bonding in structures solved by cryo-EM using the K2 Summit camera. eLife 2015;4:e06380