1m5k
From Proteopedia
(New page: 200px<br /> <applet load="1m5k" size="450" color="white" frame="true" align="right" spinBox="true" caption="1m5k, resolution 2.40Å" /> '''CRYSTAL STRUCTURE O...) |
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| - | [[Image:1m5k.gif|left|200px]]<br /> | + | [[Image:1m5k.gif|left|200px]]<br /><applet load="1m5k" size="350" color="white" frame="true" align="right" spinBox="true" |
| - | <applet load="1m5k" size=" | + | |
caption="1m5k, resolution 2.40Å" /> | caption="1m5k, resolution 2.40Å" /> | ||
'''CRYSTAL STRUCTURE OF A HAIRPIN RIBOZYME IN THE CATALYTICALLY-ACTIVE CONFORMATION'''<br /> | '''CRYSTAL STRUCTURE OF A HAIRPIN RIBOZYME IN THE CATALYTICALLY-ACTIVE CONFORMATION'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The hairpin ribozyme catalyses sequence-specific cleavage of RNA. The | + | The hairpin ribozyme catalyses sequence-specific cleavage of RNA. The active site of this natural RNA results from the docking of two irregular helices: stems A and B. One strand of stem A harbours the scissile bond. The 2.4 A resolution structure of a hairpin ribozyme-inhibitor complex reveals that the ribozyme aligns the 2'-OH nucleophile and the 5'-oxo leaving group by twisting apart the nucleotides that flank the scissile phosphate. The base of the nucleotide preceding the cleavage site is stacked within stem A; the next nucleotide, a conserved guanine, is extruded from stem A and accommodated by a highly complementary pocket in the minor groove of stem B. Metal ions are absent from the active site. The bases of four conserved purines are positioned potentially to serve as acid-base catalysts. This is the first structure determination of a fully assembled ribozyme active site that catalyses a phosphodiester cleavage without recourse to metal ions. |
==About this Structure== | ==About this Structure== | ||
| - | 1M5K is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with CA, CL, IOD and CH3 as [http://en.wikipedia.org/wiki/ligands ligands]. This structure | + | 1M5K is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Homo_sapiens Homo sapiens] with <scene name='pdbligand=CA:'>CA</scene>, <scene name='pdbligand=CL:'>CL</scene>, <scene name='pdbligand=IOD:'>IOD</scene> and <scene name='pdbligand=CH3:'>CH3</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. This structure supersedes the now removed PDB entry 1HP6. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1M5K OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Homo sapiens]] | [[Category: Homo sapiens]] | ||
[[Category: Single protein]] | [[Category: Single protein]] | ||
| - | [[Category: Amare, A | + | [[Category: Amare, A R.Ferre-D.]] |
| - | [[Category: Rupert, P | + | [[Category: Rupert, P B.]] |
[[Category: CA]] | [[Category: CA]] | ||
[[Category: CH3]] | [[Category: CH3]] | ||
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[[Category: u1a rna binding protein docked conformation]] | [[Category: u1a rna binding protein docked conformation]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:51:40 2008'' |
Revision as of 11:51, 21 February 2008
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CRYSTAL STRUCTURE OF A HAIRPIN RIBOZYME IN THE CATALYTICALLY-ACTIVE CONFORMATION
Overview
The hairpin ribozyme catalyses sequence-specific cleavage of RNA. The active site of this natural RNA results from the docking of two irregular helices: stems A and B. One strand of stem A harbours the scissile bond. The 2.4 A resolution structure of a hairpin ribozyme-inhibitor complex reveals that the ribozyme aligns the 2'-OH nucleophile and the 5'-oxo leaving group by twisting apart the nucleotides that flank the scissile phosphate. The base of the nucleotide preceding the cleavage site is stacked within stem A; the next nucleotide, a conserved guanine, is extruded from stem A and accommodated by a highly complementary pocket in the minor groove of stem B. Metal ions are absent from the active site. The bases of four conserved purines are positioned potentially to serve as acid-base catalysts. This is the first structure determination of a fully assembled ribozyme active site that catalyses a phosphodiester cleavage without recourse to metal ions.
About this Structure
1M5K is a Single protein structure of sequence from Homo sapiens with , , and as ligands. This structure supersedes the now removed PDB entry 1HP6. Full crystallographic information is available from OCA.
Reference
Crystal structure of a hairpin ribozyme-inhibitor complex with implications for catalysis., Rupert PB, Ferre-D'Amare AR, Nature. 2001 Apr 12;410(6830):780-6. PMID:11298439
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