2b7c
From Proteopedia
(New page: 200px<br /><applet load="2b7c" size="450" color="white" frame="true" align="right" spinBox="true" caption="2b7c, resolution 1.8Å" /> '''Yeast guanine nucleot...) |
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| - | [[Image:2b7c.gif|left|200px]]<br /><applet load="2b7c" size=" | + | [[Image:2b7c.gif|left|200px]]<br /><applet load="2b7c" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2b7c, resolution 1.8Å" /> | caption="2b7c, resolution 1.8Å" /> | ||
'''Yeast guanine nucleotide exchange factor eEF1Balpha K205A mutant in complex with eEF1A'''<br /> | '''Yeast guanine nucleotide exchange factor eEF1Balpha K205A mutant in complex with eEF1A'''<br /> | ||
==Overview== | ==Overview== | ||
| - | To sustain efficient translation, eukaryotic elongation factor B alpha | + | To sustain efficient translation, eukaryotic elongation factor B alpha (eEF1B alpha) functions as the guanine nucleotide exchange factor for eEF1A. Stopped-flow kinetics using 2'-(or 3')-O-N-methylanthraniloyl (mant)-GDP showed spontaneous release of nucleotide from eEF1A is extremely slow and accelerated 700-fold by eEF1B alpha. The eEF1B alpha-stimulated reaction was inhibited by Mg2+ with a K(1/2) of 3.8 mM. Previous structural studies predicted the Lys-205 residue of eEF1B alpha plays an important role in promoting nucleotide exchange by disrupting the Mg2+ binding site. Co-crystal structures of the lethal K205A mutant in the catalytic C terminus of eEF1B alpha with eEF1A and eEF1A.GDP established that the lethality was not due to a structural defect. Instead, the K205A mutant drastically reduced the nucleotide exchange activity even at very low concentrations of Mg2+. A K205R eEF1B alpha mutant on the other hand was functional in vivo and showed nearly wild-type nucleotide dissociation rates but almost no sensitivity to Mg2+. These results indicate the significant role of Mg2+ in the nucleotide exchange reaction by eEF1B alpha and establish the catalytic function of Lys-205 in displacing Mg2+ from its binding site. |
==About this Structure== | ==About this Structure== | ||
| - | 2B7C is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae]. Full crystallographic information is available from [http:// | + | 2B7C is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Saccharomyces_cerevisiae Saccharomyces cerevisiae]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2B7C OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Protein complex]] | [[Category: Protein complex]] | ||
[[Category: Saccharomyces cerevisiae]] | [[Category: Saccharomyces cerevisiae]] | ||
| - | [[Category: Andersen, G | + | [[Category: Andersen, G R.]] |
| - | [[Category: Jeppesen, M | + | [[Category: Jeppesen, M G.]] |
| - | [[Category: Kinzy, T | + | [[Category: Kinzy, T G.]] |
[[Category: Patel, S.]] | [[Category: Patel, S.]] | ||
| - | [[Category: Pittman, Y | + | [[Category: Pittman, Y R.]] |
[[Category: Valente, L.]] | [[Category: Valente, L.]] | ||
[[Category: eef1a]] | [[Category: eef1a]] | ||
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[[Category: g-protein/gef complex]] | [[Category: g-protein/gef complex]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:34:52 2008'' |
Revision as of 14:34, 21 February 2008
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Yeast guanine nucleotide exchange factor eEF1Balpha K205A mutant in complex with eEF1A
Overview
To sustain efficient translation, eukaryotic elongation factor B alpha (eEF1B alpha) functions as the guanine nucleotide exchange factor for eEF1A. Stopped-flow kinetics using 2'-(or 3')-O-N-methylanthraniloyl (mant)-GDP showed spontaneous release of nucleotide from eEF1A is extremely slow and accelerated 700-fold by eEF1B alpha. The eEF1B alpha-stimulated reaction was inhibited by Mg2+ with a K(1/2) of 3.8 mM. Previous structural studies predicted the Lys-205 residue of eEF1B alpha plays an important role in promoting nucleotide exchange by disrupting the Mg2+ binding site. Co-crystal structures of the lethal K205A mutant in the catalytic C terminus of eEF1B alpha with eEF1A and eEF1A.GDP established that the lethality was not due to a structural defect. Instead, the K205A mutant drastically reduced the nucleotide exchange activity even at very low concentrations of Mg2+. A K205R eEF1B alpha mutant on the other hand was functional in vivo and showed nearly wild-type nucleotide dissociation rates but almost no sensitivity to Mg2+. These results indicate the significant role of Mg2+ in the nucleotide exchange reaction by eEF1B alpha and establish the catalytic function of Lys-205 in displacing Mg2+ from its binding site.
About this Structure
2B7C is a Protein complex structure of sequences from Saccharomyces cerevisiae. Full crystallographic information is available from OCA.
Reference
Mg2+ and a key lysine modulate exchange activity of eukaryotic translation elongation factor 1B alpha., Pittman YR, Valente L, Jeppesen MG, Andersen GR, Patel S, Kinzy TG, J Biol Chem. 2006 Jul 14;281(28):19457-68. Epub 2006 May 4. PMID:16675455
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