1iuh
From Proteopedia
(New page: 200px<br /><applet load="1iuh" size="450" color="white" frame="true" align="right" spinBox="true" caption="1iuh, resolution 2.50Å" /> '''Crystal structure of...) |
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| - | [[Image:1iuh.gif|left|200px]]<br /><applet load="1iuh" size=" | + | [[Image:1iuh.gif|left|200px]]<br /><applet load="1iuh" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1iuh, resolution 2.50Å" /> | caption="1iuh, resolution 2.50Å" /> | ||
'''Crystal structure of TT0787 of thermus thermophilus HB8'''<br /> | '''Crystal structure of TT0787 of thermus thermophilus HB8'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The 2'-5' RNA ligase family members are bacterial and archaeal RNA ligases | + | The 2'-5' RNA ligase family members are bacterial and archaeal RNA ligases that ligate 5' and 3' half-tRNA molecules with 2',3'-cyclic phosphate and 5'-hydroxyl termini, respectively, to the product containing the 2'-5' phosphodiester linkage. Here, the crystal structure of the 2'-5' RNA ligase protein from an extreme thermophile, Thermus thermophilus HB8, was solved at 2.5A resolution. The structure of the 2'-5' RNA ligase superimposes well on that of the Arabidopsis thaliana cyclic phosphodiesterase (CPDase), which hydrolyzes ADP-ribose 1",2"-cyclic phosphate (a product of the tRNA splicing reaction) to the monoester ADP-ribose 1"-phosphate. Although the sequence identity between the two proteins is remarkably low (9.3%), the 2'-5' RNA ligase and CPDase structures have two HX(T/S)X motifs in their corresponding positions. The HX(T/S)X motifs play important roles in the CPDase activity, and are conserved in both the CPDases and 2'-5' RNA ligases. Therefore, the catalytic mechanism of the 2'-5' RNA ligase may be similar to that of the CPDase. On the other hand, the electrostatic potential of the cavity of the 2'-5' RNA ligase is positive, but that of the CPDase is negative. Furthermore, in the CPDase, two loops with low B-factors cover the cavity. In contrast, in the 2'-5' RNA ligase, the corresponding loops form an open conformation and are flexible. These characteristics may be due to the differences in the substrates, tRNA and ADP-ribose 1",2"-cyclic phosphate. |
==About this Structure== | ==About this Structure== | ||
| - | 1IUH is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermus_thermophilus Thermus thermophilus]. Full crystallographic information is available from [http:// | + | 1IUH is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Thermus_thermophilus Thermus thermophilus]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1IUH OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Kato, M.]] | [[Category: Kato, M.]] | ||
[[Category: Kuramitsu, S.]] | [[Category: Kuramitsu, S.]] | ||
| - | [[Category: RSGI, RIKEN | + | [[Category: RSGI, RIKEN Structural Genomics/Proteomics Initiative.]] |
[[Category: Sakai, H.]] | [[Category: Sakai, H.]] | ||
[[Category: Shirouzu, M.]] | [[Category: Shirouzu, M.]] | ||
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[[Category: thermus thermophilus]] | [[Category: thermus thermophilus]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:15:46 2008'' |
Revision as of 11:15, 21 February 2008
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Crystal structure of TT0787 of thermus thermophilus HB8
Overview
The 2'-5' RNA ligase family members are bacterial and archaeal RNA ligases that ligate 5' and 3' half-tRNA molecules with 2',3'-cyclic phosphate and 5'-hydroxyl termini, respectively, to the product containing the 2'-5' phosphodiester linkage. Here, the crystal structure of the 2'-5' RNA ligase protein from an extreme thermophile, Thermus thermophilus HB8, was solved at 2.5A resolution. The structure of the 2'-5' RNA ligase superimposes well on that of the Arabidopsis thaliana cyclic phosphodiesterase (CPDase), which hydrolyzes ADP-ribose 1",2"-cyclic phosphate (a product of the tRNA splicing reaction) to the monoester ADP-ribose 1"-phosphate. Although the sequence identity between the two proteins is remarkably low (9.3%), the 2'-5' RNA ligase and CPDase structures have two HX(T/S)X motifs in their corresponding positions. The HX(T/S)X motifs play important roles in the CPDase activity, and are conserved in both the CPDases and 2'-5' RNA ligases. Therefore, the catalytic mechanism of the 2'-5' RNA ligase may be similar to that of the CPDase. On the other hand, the electrostatic potential of the cavity of the 2'-5' RNA ligase is positive, but that of the CPDase is negative. Furthermore, in the CPDase, two loops with low B-factors cover the cavity. In contrast, in the 2'-5' RNA ligase, the corresponding loops form an open conformation and are flexible. These characteristics may be due to the differences in the substrates, tRNA and ADP-ribose 1",2"-cyclic phosphate.
About this Structure
1IUH is a Single protein structure of sequence from Thermus thermophilus. Full crystallographic information is available from OCA.
Reference
Crystal structure of the 2'-5' RNA ligase from Thermus thermophilus HB8., Kato M, Shirouzu M, Terada T, Yamaguchi H, Murayama K, Sakai H, Kuramitsu S, Yokoyama S, J Mol Biol. 2003 Jun 20;329(5):903-11. PMID:12798681
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