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1i3y
From Proteopedia
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|PDB= 1i3y |SIZE=350|CAPTION= <scene name='initialview01'>1i3y</scene> | |PDB= 1i3y |SIZE=350|CAPTION= <scene name='initialview01'>1i3y</scene> | ||
|SITE= | |SITE= | ||
| - | |LIGAND= | + | |LIGAND= <scene name='pdbligand=A:ADENOSINE-5'-MONOPHOSPHATE'>A</scene>, <scene name='pdbligand=C:CYTIDINE-5'-MONOPHOSPHATE'>C</scene>, <scene name='pdbligand=G:GUANOSINE-5'-MONOPHOSPHATE'>G</scene>, <scene name='pdbligand=OMU:O2'-METHYLURIDINE+5'-MONOPHOSPHATE'>OMU</scene>, <scene name='pdbligand=U:URIDINE-5'-MONOPHOSPHATE'>U</scene> |
|ACTIVITY= | |ACTIVITY= | ||
|GENE= | |GENE= | ||
| + | |DOMAIN= | ||
| + | |RELATEDENTRY=[[1i3x|1I3X]] | ||
| + | |RESOURCES=<span class='plainlinks'>[http://oca.weizmann.ac.il/oca-docs/fgij/fg.htm?mol=1i3y FirstGlance], [http://oca.weizmann.ac.il/oca-bin/ocaids?id=1i3y OCA], [http://www.ebi.ac.uk/pdbsum/1i3y PDBsum], [http://www.rcsb.org/pdb/explore.do?structureId=1i3y RCSB]</span> | ||
}} | }} | ||
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[[Category: a site]] | [[Category: a site]] | ||
| - | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Sun Mar 30 21:14:17 2008'' |
Revision as of 18:14, 30 March 2008
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| Ligands: | , , , , | ||||||
| Related: | 1I3X
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| Resources: | FirstGlance, OCA, PDBsum, RCSB | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
SOLUTION STRUCTURE OF THE A LOOP OF 23S RIBOSOMAL RNA.
Overview
The A loop is an essential RNA component of the ribosome peptidyltransferase center that directly interacts with aminoacyl (A)-site tRNA. The A loop is highly conserved and contains a ubiquitous 2'-O-methyl ribose modification at position U2552. Here, we present the solution structure of a modified and unmodified A-loop RNA to define both the A-loop fold and the structural impact of the U2552 modification. Solution data reveal that the A-loop RNA has a compact structure that includes a noncanonical base pair between C2556 and U2552. NMR evidence is presented that the N3 position of C2556 has a shifted pKa and that protonation at C2556-N3 changes the C-U pair geometry. Our data indicate that U2552 methylation modifies the A-loop fold, in particular the dynamics and position of residues C2556 and U2555. We compare our structural data with the structure of the A loop observed in a recent 50S crystal structure [Ban, N., Nissen, P., Hansen, J., Moore, P. B. & Steitz, T. A. (2000) Science 289, 905--920; Nissen, P., Hansen, J., Ban, N., Moore, P. B. & Steitz, T. A. (2000) Science 289, 920--930]. The solution and crystal structures of the A loop are dramatically different, suggesting that a structural rearrangement of the A loop must occur on docking into the peptidyltransferase center. Possible roles of this docking event, the shifted pKa of C2556 and the U2552 2'-O-methylation in the mechanism of translation, are discussed.
About this Structure
1I3Y is a Protein complex structure of sequences from [1]. Full crystallographic information is available from OCA.
Reference
Solution structure of the A loop of 23S ribosomal RNA., Blanchard SC, Puglisi JD, Proc Natl Acad Sci U S A. 2001 Mar 27;98(7):3720-5. Epub 2001 Mar 20. PMID:11259644
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