Structure and Function of the Ribosome

Ribosomes, the ancient and universal cellular machines, are responsible for decoding genetic information and synthesizing proteins in all living organisms. A eubacterial ribosome has a molecular weight of approximately 2.5 MDa and consists of about 55 proteins and 3 large RNA molecules. So far, the ribosome is the largest asymmetric macromolecule amenable to crystallographic analyses.

The multi-step process of translation is not fully understood: only recently, structural details of some steps of translation started to emerge.

In our lab, we aim at a full structural description of the highly dynamic process of translation. We use X-ray crystallography to obtain snapshots of different functional states of the ribosome and biochemistry to test the hypotheses concerning the mechanisms and dynamics of the ribosome and translation factors. These studies are designed not only to expand our fundamental knowledge of this molecular machine but also to aid in the development of new drugs that target ribosomes.

Translation termination on the 70S ribosome.Release factor RF2 (yellow) is bound to the ribosome in response to a stop codon encoded in a messenger RNA (green) located on the small 30S ribosomal subunit (cyan and blue). RF2 is positioned to catalyze the hydrolysis of a peptidyl-tRNA (green and orange) on the large 50S subunit (grey, purple and magenta). An E-site-bound tRNA is in red.

This structural model was rendered in Pymol and is based on the X-ray structures of 70S translation termination complexes (Korostelev et al., 2008; Laurberg et al., 2008) and a 70S-tRNA complex (Jenner et al., 2010).