Welcome to the Ribosome Crystallography Group

Our group takes a multi-disciplinary approach, using X-ray crystallography, Nuclear Magnetic Resonance (NMR), Mass Spectrometry (MS) and cryo-electron microscopy (EM), to understand how the ribosome is regulated in the cell.

Our projects encompasses the factors involved in the regulation of ribosomal subunit assembly such as Era, the inactivation of the ribosome by (i) antibiotics or (ii) under stress conditions by protein factors such as RMF, to regulation of translation through (i) binding of factors, such as RRF during ribosome recycling, (ii) interaction of the nascent polypeptide chain with the ribosomal tunnel or (iii) via modulating the composition of the ribosome itself.

The Ribosome:

In every organism, translation of the genetic code into functional proteins is performed on the ribosome, a macromolecular machine of more than 2.3 MDa. In the eubacteria Escherichia coli the ribosome is assembled from at least 55 different proteins and three RNA molecules (23S, 16S and 5S rRNA). This intact species is termed the 70S ribosome and is made up of two distinct components, the 30S and 50S subunits.

30S Thermus thermophilus	50S Deinococcus radiodurans

The high-resolution structures of the small (30S) and large (50S) ribosome subunit, in the past few years have revolutionized our understanding of ribosome structure and function.

In our group we are in the unique position of being able to prepare five different types of ribosome crystals:

1. Thermus thermophilus 30S subunits,
2. Thermus thermophilus 50S subunits,
3. Deinococcus radiodurans 50S subunits,
4. Haloarcula marismortui 50S subunits and
5. Thermus thermophilus 70S ribosomes.

(see crystal gallery for more)

Because protein synthesis is such a central and important process to all living cells, multiple regulation systems have developed to fine-tune translation in response to environmental fluctuations. Indeed, the importance of translation is illustrated by the multitude of antibiotics that target the active sites of the ribosome, as well as the extreme conservation in the portions of the rRNA generally but specifically at these active centers .

Three regions on the 50S are targetted (shown in red), these include the active site for peptide bond formation (the peptidyltransferase centre), the ribosomal tunnel (through which the nascent chain passes) and the factor binding site (often referred to as the GTPase activation centre). On the 30S subunit, the tRNA binding sites are predominantly targetted (shown in red), especially the A site, where the tRNA-mRNA decoding process is monitored.