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 subunits, denoted 30S and 50S in bacteria. Here we report the crystal structure of the 30S subunit from Thermus thermophilus, refined to 3 Å resolution. The final atomic model rationalizes over four decades of biochemical data on the ribosome, and provides a wealth of information about RNA and protein 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 will facilitate the interpretation in molecular terms of lower resolution structural data on several functional states of the ribosome from electron microscopy and crystallography.

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Figure 1: Electron density maps of the 30S.
Figure 2: Overview of the 30S structure.
Figure 3: Different modes of interhelical packing in 16S RNA.
Figure 4: Structure of the 5′ domain of 16S RNA.
Figure 5: Structure of the central domain of 16S RNA.
Figure 6: Structure of the 3′ major and 3′ minor domains of 16S RNA.
Figure 7: Proteins from the central and 5′ domains.
Figure 9: Proteins from the head.
Figure 8: Proteins near the functional centre of the 30S.


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This work was supported by the Medical Research Council (UK) and a US National Institutes of Health grant to V.R. and S. W. White. Beamlines at Argonne and Brookhaven were supported by the US Department of Energy. D.E.B. was supported by an EMBO long-term postdoctoral fellowship,and W.M.C. by an NIH predoctoral fellowship. We thank B. S. Brunschwig and M. H. Chou for gifts of osmium hexammine and osmium bipyridine; T. Terwilliger for help with phasing using SOLVE; T. A. Leaf-Jones for providing us a version of O with RNA tools; and our colleagues at the LMB for their advice and encouragement. We are indebted to A. Joachimiak, S. L. Ginell, R. Ravelli, S. McSweeney, G. Leonard, A. Thompson, H. Lewis, L. Berman, M. Papiz, S. Girdwood and M. MacDonald for help and advice on synchrotron beamlines.

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Correspondence to V. Ramakrishnan.

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Wimberly, B., Brodersen, D., Clemons, W. et al. Structure of the 30S ribosomal subunit. Nature 407, 327–339 (2000).

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