Structure of the 30S ribosomal subunit

Genetic information encoded in messenger RNA is translated into protein by the ribosome, which is a large nucleoprotein complex comprising two subunit s, denoted 30S and 50S in bacteria. Here we report the crystal structure of the 30S subunit from Thermus thermophilus, refined to 3 Angstrom resolutio n. The final atomic model rationalizes over four decades of biochemical dat a on the ribosome, and provides a wealth of information about RNA and prote in structure, protein-RNA interactions and ribosome assembly. It is also a structural basis for analysis of the functions of the 30S subunit, such as decoding, and for understanding the action of antibiotics. The structure wi ll facilitate the interpretation in molecular terms of lower resolution str uctural data on several functional states of the ribosome from electron mic roscopy and crystallography.