Atom-by-atom structure of a bacterium ribosome. Credit: Arto Pulk, University of California, Berkeley.

This is the first atomic-resolution image of the protein-building ribosome bound to the molecule that controls its motion (center of the picture). Using high-energy protein crystallography, researchers obtained the pair's structure and used it to learn that the molecule moves the ribosome by reshaping itself after interacting with an energy-carrying molecule. The molecule's reconfiguration allows the ribosome to manipulate mRNA and tRNA, two molecules needed for protein building in the cell. The finding could lead to better antibiotics that interfere with the ribosome's movement in bacteria and kills them.

Featured in the July 18, 2013, issue of Biomedical Beat.