2ayi
From Proteopedia
(New page: 200px<br /><applet load="2ayi" size="450" color="white" frame="true" align="right" spinBox="true" caption="2ayi, resolution 3.70Å" /> '''Wild-type AmpT from ...) |
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| - | [[Image:2ayi.gif|left|200px]]<br /><applet load="2ayi" size=" | + | [[Image:2ayi.gif|left|200px]]<br /><applet load="2ayi" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="2ayi, resolution 3.70Å" /> | caption="2ayi, resolution 3.70Å" /> | ||
'''Wild-type AmpT from Thermus thermophilus'''<br /> | '''Wild-type AmpT from Thermus thermophilus'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Aminopeptidase T (AmpT) from Thermus thermophilus is a metalloexopeptidase | + | Aminopeptidase T (AmpT) from Thermus thermophilus is a metalloexopeptidase with no similarity to prototypical metallopeptidases with an HExxH or HxxEH motif. The crystal structure of the Staphylococcus aureus homologue of AmpT, which is known as aminopeptidase S (AmpS), has been reported recently. This structure revealed a dimeric protein with a very unusual, elongated shape and a large internal cavity. The active sites were found on the inner walls of the cavity and were entirely shielded from the environment, which suggested either that the dimer in the crystals was not physiologically relevant, or that an inactive conformation had been crystallized. Here, we show by gel-filtration and analytical ultracentrifugation that AmpT, like AmpS, forms dimers in solution, and we present the structure of AmpT in a crystal form with five protomers in the asymmetric unit. The five protomers take conformations that range from fully closed, as in the AmpS structure, to nearly open, so that the active site is almost directly accessible. The different conformations indicate flexibility between the AmpT N and C-domains, and explain how AmpT can be active, although the unusual AmpS dimerization mode applies to AmpT as well. |
==About this Structure== | ==About this Structure== | ||
| - | 2AYI is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermus_thermophilus Thermus thermophilus] with ZN as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 2AYI is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermus_thermophilus Thermus thermophilus] with <scene name='pdbligand=ZN:'>ZN</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=2AYI OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Bochtler, M.]] | [[Category: Bochtler, M.]] | ||
[[Category: Bourenkov, G.]] | [[Category: Bourenkov, G.]] | ||
| - | [[Category: Odintsov, S | + | [[Category: Odintsov, S G.]] |
[[Category: Rybin, V.]] | [[Category: Rybin, V.]] | ||
[[Category: Sabala, I.]] | [[Category: Sabala, I.]] | ||
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[[Category: metallopeptidase]] | [[Category: metallopeptidase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:32:20 2008'' |
Revision as of 14:32, 21 February 2008
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Wild-type AmpT from Thermus thermophilus
Overview
Aminopeptidase T (AmpT) from Thermus thermophilus is a metalloexopeptidase with no similarity to prototypical metallopeptidases with an HExxH or HxxEH motif. The crystal structure of the Staphylococcus aureus homologue of AmpT, which is known as aminopeptidase S (AmpS), has been reported recently. This structure revealed a dimeric protein with a very unusual, elongated shape and a large internal cavity. The active sites were found on the inner walls of the cavity and were entirely shielded from the environment, which suggested either that the dimer in the crystals was not physiologically relevant, or that an inactive conformation had been crystallized. Here, we show by gel-filtration and analytical ultracentrifugation that AmpT, like AmpS, forms dimers in solution, and we present the structure of AmpT in a crystal form with five protomers in the asymmetric unit. The five protomers take conformations that range from fully closed, as in the AmpS structure, to nearly open, so that the active site is almost directly accessible. The different conformations indicate flexibility between the AmpT N and C-domains, and explain how AmpT can be active, although the unusual AmpS dimerization mode applies to AmpT as well.
About this Structure
2AYI is a Single protein structure of sequence from Thermus thermophilus with as ligand. Full crystallographic information is available from OCA.
Reference
Substrate access to the active sites in aminopeptidase T, a representative of a new metallopeptidase clan., Odintsov SG, Sabala I, Bourenkov G, Rybin V, Bochtler M, J Mol Biol. 2005 Nov 25;354(2):403-12. Epub 2005 Sep 30. PMID:16242715
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