Crystal Structure of the Ribosome at 5.5

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Crystal Structure of the Ribosome at 5.5 Å
Resolution

• Marat M. Yusupov,1 Gulnara Zh. Yusupova,1
  Albion Baucom,1 Kate Lieberman,1 Thomas N.
  Earnest,2 J. H. D. Cate,3 Harry F. Noller1
• 1 Center for Molecular Biology of RNA, Sinsheimer
  Laboratories, University of California at Santa
  Cruz, Santa Cruz, CA 95064, USA. 2 Berkeley
  Center for Structural Biology, Physical
  Biosciences Division, Lawrence Berkeley National
  Laboratory, Berkeley, CA 94720, USA. 3 Whitehead
  Institute, Cambridge, MA 01242, USA.

2

• Describe the three-dimensional structure of the
  70S ribosome of the completed Thermus
  thermophilus containing mRNA and tRNA bound to
  the A and E site at 5.5 Å resulution and to the A
  site at 7 Å resolution.
• Overrall structure of the 70s ribosome.
• The densityof tRNA, bound to the P site of the
  70S ribosome, at 5.5 Å resolution.
• Views of the stucture of the T.thermophilus 70S
  ribosome.
• Secondary and tertiary structure of 16S, 23S,and
  5S RNA.
• Differences between the conformations of
  70Sribosomes and isolated subunits.
• Stuctures of the intersubunit bridges.
• tRNA-ribosome interactions.
• Implications for the mechanism of translation.

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Electron density of tRNAMetf bound to the P site
of the 70S ribosome, at 5.5 Å resolution
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Subunits of prokaryotic ribosomes(70S)
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• A30s??????
• B???(30S???,50S?)
• C?50S?????
• D???
• E???(50S?)
• F50S???(interface,)
• G300S???(A??180?)
• ??23SRNA???5SRNA???16SRNA???50S????A???P
  ???E??

70S??????


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Secondary and tertiary structures of 16S, 23S,
and 5S rRNAs (A16SRNA B23S, 5SRNA
CThree-dimentional fold of 16s RNA D
CThree-dimentional fold of 23S and 5s RNA.)
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Conformational differences between rRNAs in 70S
ribosomes and 30S and 50S subunits
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Intersubunit bridges
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Intersubunit bridges(continued)
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• tRNA-ribosome interactions

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Two views of the A-tRNA anticodon stem loop bound
to its codon in the 30S subunit A site
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1. Interaction of E-tRNA with the ribosome.
2. Secondary structures of 16S and 23S rRNA,
   showing molecular contacts with A-tRNA (gold),
   P-tRNA (orange), and E-tRNA (red)

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