1coj
From Proteopedia
(New page: 200px<br /><applet load="1coj" size="450" color="white" frame="true" align="right" spinBox="true" caption="1coj, resolution 1.9Å" /> '''FE-SOD FROM AQUIFEX P...) |
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| - | [[Image:1coj.jpg|left|200px]]<br /><applet load="1coj" size=" | + | [[Image:1coj.jpg|left|200px]]<br /><applet load="1coj" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1coj, resolution 1.9Å" /> | caption="1coj, resolution 1.9Å" /> | ||
'''FE-SOD FROM AQUIFEX PYROPHILUS, A HYPERTHERMOPHILIC BACTERIUM'''<br /> | '''FE-SOD FROM AQUIFEX PYROPHILUS, A HYPERTHERMOPHILIC BACTERIUM'''<br /> | ||
==Overview== | ==Overview== | ||
| - | Superoxide dismutase (SOD) from Aquifex pyrophilus, a hyperthermophilic | + | Superoxide dismutase (SOD) from Aquifex pyrophilus, a hyperthermophilic bacterium, is an extremely heat-stable enzyme that maintains about 70% of its activity after heat treatment for 60 minutes at 100 degrees C. To understand the molecular basis of thermostability of this enzyme, we have determined the crystal structure of A. pyrophilus superoxide dismutase (Ap SOD), an Fe containing homotetrameric enzyme, at 1.9 A resolution, and compared it with SOD structures from a mesophile and a thermophile, and other enzyme structures from other hyperthermophiles. The structure has been refined to a crystallographic R-factor (I > 2sigma) of 17.0% and R-free (I > 2sigma) of 19.9%. While the overall structure of the Ap SOD monomer is similar to the other SODs, significant conformational differences are observed in a highly variable loop region and the C-terminal helix. The conformational differences in these regions alter the subunit arrangement of this enzyme and generate a very compact tetramer. Structural comparisons of three SODs have revealed that Ap SOD has some stabilizing features at both the tertiary and the quaternary structural level: The Ap SOD monomer contains a large number of ion-pairs and the Ap SOD tetramer has a dramatically increased buried surface area per monomer. Comparisons of the Ap SOD structure with that of other known enzymes from hyperthermophiles reveal that the increased number of intrasubunit ion-pairs is a common feature. |
==About this Structure== | ==About this Structure== | ||
| - | 1COJ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Aquifex_pyrophilus Aquifex pyrophilus] with FE as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1COJ is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Aquifex_pyrophilus Aquifex pyrophilus] with <scene name='pdbligand=FE:'>FE</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1COJ OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Aquifex pyrophilus]] | [[Category: Aquifex pyrophilus]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Ahn, B | + | [[Category: Ahn, B Y.]] |
| - | [[Category: Cho, S | + | [[Category: Cho, S J.]] |
[[Category: Cho, Y.]] | [[Category: Cho, Y.]] | ||
| - | [[Category: Han, Y | + | [[Category: Han, Y S.]] |
| - | [[Category: Kim, S | + | [[Category: Kim, S H.]] |
| - | [[Category: Lim, J | + | [[Category: Lim, J H.]] |
| - | [[Category: Yu, Y | + | [[Category: Yu, Y G.]] |
[[Category: FE]] | [[Category: FE]] | ||
[[Category: oxidoreductase]] | [[Category: oxidoreductase]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:08:10 2008'' |
Revision as of 10:08, 21 February 2008
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FE-SOD FROM AQUIFEX PYROPHILUS, A HYPERTHERMOPHILIC BACTERIUM
Overview
Superoxide dismutase (SOD) from Aquifex pyrophilus, a hyperthermophilic bacterium, is an extremely heat-stable enzyme that maintains about 70% of its activity after heat treatment for 60 minutes at 100 degrees C. To understand the molecular basis of thermostability of this enzyme, we have determined the crystal structure of A. pyrophilus superoxide dismutase (Ap SOD), an Fe containing homotetrameric enzyme, at 1.9 A resolution, and compared it with SOD structures from a mesophile and a thermophile, and other enzyme structures from other hyperthermophiles. The structure has been refined to a crystallographic R-factor (I > 2sigma) of 17.0% and R-free (I > 2sigma) of 19.9%. While the overall structure of the Ap SOD monomer is similar to the other SODs, significant conformational differences are observed in a highly variable loop region and the C-terminal helix. The conformational differences in these regions alter the subunit arrangement of this enzyme and generate a very compact tetramer. Structural comparisons of three SODs have revealed that Ap SOD has some stabilizing features at both the tertiary and the quaternary structural level: The Ap SOD monomer contains a large number of ion-pairs and the Ap SOD tetramer has a dramatically increased buried surface area per monomer. Comparisons of the Ap SOD structure with that of other known enzymes from hyperthermophiles reveal that the increased number of intrasubunit ion-pairs is a common feature.
About this Structure
1COJ is a Single protein structure of sequence from Aquifex pyrophilus with as ligand. Full crystallographic information is available from OCA.
Reference
The crystal structure of an Fe-superoxide dismutase from the hyperthermophile Aquifex pyrophilus at 1.9 A resolution: structural basis for thermostability., Lim JH, Yu YG, Han YS, Cho S, Ahn BY, Kim SH, Cho Y, J Mol Biol. 1997 Jul 11;270(2):259-74. PMID:9236127
Page seeded by OCA on Thu Feb 21 12:08:10 2008
Categories: Aquifex pyrophilus | Single protein | Ahn, B Y. | Cho, S J. | Cho, Y. | Han, Y S. | Kim, S H. | Lim, J H. | Yu, Y G. | FE | Oxidoreductase
