1b23
From Proteopedia
(New page: 200px<br /><applet load="1b23" size="450" color="white" frame="true" align="right" spinBox="true" caption="1b23, resolution 2.6Å" /> '''E. coli cysteinyl-tRN...) |
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| - | [[Image:1b23.gif|left|200px]]<br /><applet load="1b23" size=" | + | [[Image:1b23.gif|left|200px]]<br /><applet load="1b23" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1b23, resolution 2.6Å" /> | caption="1b23, resolution 2.6Å" /> | ||
'''E. coli cysteinyl-tRNA and T. aquaticus elongation factor EF-TU:GTP ternary complex'''<br /> | '''E. coli cysteinyl-tRNA and T. aquaticus elongation factor EF-TU:GTP ternary complex'''<br /> | ||
==Overview== | ==Overview== | ||
| - | BACKGROUND:. The translation elongation factor EF-Tu in its GTP-bound | + | BACKGROUND:. The translation elongation factor EF-Tu in its GTP-bound state forms a ternary complex with any aminoacylated tRNA (aa-tRNA), except initiator tRNA and selenocysteinyl-tRNA. This complex delivers aa-tRNA to the ribosomal A site during the elongation cycle of translation. The crystal structure of the yeast Phe-tRNAPhe ternary complex with Thermus aquaticus EF-Tu-GDPNP (Phe-TC) has previously been determined as one representative of this general yet highly discriminating complex formation. RESULTS: The ternary complex of Escherichia coli Cys-tRNACys and T. aquaticus EF-Tu-GDPNP (Cys-TC) has been solved and refined at 2.6 degrees resolution. Conserved and variable features of the aa-tRNA recognition and binding by EF-Tu-GTP have been revealed by comparison with the Phe-TC structure. New tertiary interactions are observed in the tRNACys structure. A 'kissing complex' is observed in the very close crystal packing arrangement. CONCLUSIONS: The recognition of Cys-tRNACys by EF-Tu-GDPNP is restricted to the aa-tRNA motif previously identified in Phe-TC and consists of the aminoacylated 3' end, the phosphorylated 5' end and one side of the acceptor stem and T stem. The aminoacyl bond is recognized somewhat differently, yet by the same primary motif in EF-Tu, which suggests that EF-Tu adapts to subtle variations in this moiety among all aa-tRNAs. New tertiary interactions revealed by the Cys-tRNACys structure, such as a protonated C16:C59 pyrimidine pair, a G15:G48 'Levitt pair' and an s4U8:A14:A46 base triple add to the generic understanding of tRNA structure from sequence. The structure of the 'kissing complex' shows a quasicontinuous helix with a distinct shape determined by the number of base pairs. |
==About this Structure== | ==About this Structure== | ||
| - | 1B23 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] and [http://en.wikipedia.org/wiki/Thermus_aquaticus Thermus aquaticus] with MG, SO4, CYS and GNP as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http:// | + | 1B23 is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Escherichia_coli Escherichia coli] and [http://en.wikipedia.org/wiki/Thermus_aquaticus Thermus aquaticus] with <scene name='pdbligand=MG:'>MG</scene>, <scene name='pdbligand=SO4:'>SO4</scene>, <scene name='pdbligand=CYS:'>CYS</scene> and <scene name='pdbligand=GNP:'>GNP</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1B23 OCA]. |
==Reference== | ==Reference== | ||
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[[Category: translation elongation factor]] | [[Category: translation elongation factor]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 11:50:36 2008'' |
Revision as of 09:50, 21 February 2008
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E. coli cysteinyl-tRNA and T. aquaticus elongation factor EF-TU:GTP ternary complex
Overview
BACKGROUND:. The translation elongation factor EF-Tu in its GTP-bound state forms a ternary complex with any aminoacylated tRNA (aa-tRNA), except initiator tRNA and selenocysteinyl-tRNA. This complex delivers aa-tRNA to the ribosomal A site during the elongation cycle of translation. The crystal structure of the yeast Phe-tRNAPhe ternary complex with Thermus aquaticus EF-Tu-GDPNP (Phe-TC) has previously been determined as one representative of this general yet highly discriminating complex formation. RESULTS: The ternary complex of Escherichia coli Cys-tRNACys and T. aquaticus EF-Tu-GDPNP (Cys-TC) has been solved and refined at 2.6 degrees resolution. Conserved and variable features of the aa-tRNA recognition and binding by EF-Tu-GTP have been revealed by comparison with the Phe-TC structure. New tertiary interactions are observed in the tRNACys structure. A 'kissing complex' is observed in the very close crystal packing arrangement. CONCLUSIONS: The recognition of Cys-tRNACys by EF-Tu-GDPNP is restricted to the aa-tRNA motif previously identified in Phe-TC and consists of the aminoacylated 3' end, the phosphorylated 5' end and one side of the acceptor stem and T stem. The aminoacyl bond is recognized somewhat differently, yet by the same primary motif in EF-Tu, which suggests that EF-Tu adapts to subtle variations in this moiety among all aa-tRNAs. New tertiary interactions revealed by the Cys-tRNACys structure, such as a protonated C16:C59 pyrimidine pair, a G15:G48 'Levitt pair' and an s4U8:A14:A46 base triple add to the generic understanding of tRNA structure from sequence. The structure of the 'kissing complex' shows a quasicontinuous helix with a distinct shape determined by the number of base pairs.
About this Structure
1B23 is a Single protein structure of sequence from Escherichia coli and Thermus aquaticus with , , and as ligands. Full crystallographic information is available from OCA.
Reference
The crystal structure of Cys-tRNACys-EF-Tu-GDPNP reveals general and specific features in the ternary complex and in tRNA., Nissen P, Thirup S, Kjeldgaard M, Nyborg J, Structure. 1999 Feb 15;7(2):143-56. PMID:10368282
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