1fsi
From Proteopedia
(New page: 200px<br /><applet load="1fsi" size="450" color="white" frame="true" align="right" spinBox="true" caption="1fsi, resolution 2.50Å" /> '''CRYSTAL STRUCTURE OF...) |
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| - | [[Image:1fsi.gif|left|200px]]<br /><applet load="1fsi" size=" | + | [[Image:1fsi.gif|left|200px]]<br /><applet load="1fsi" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1fsi, resolution 2.50Å" /> | caption="1fsi, resolution 2.50Å" /> | ||
'''CRYSTAL STRUCTURE OF CYCLIC NUCLEOTIDE PHOSPHODIESTERASE OF APPR>P FROM ARABIDOPSIS THALIANA'''<br /> | '''CRYSTAL STRUCTURE OF CYCLIC NUCLEOTIDE PHOSPHODIESTERASE OF APPR>P FROM ARABIDOPSIS THALIANA'''<br /> | ||
==Overview== | ==Overview== | ||
| - | The crystal structure of the cyclic phosphodiesterase (CPDase) from | + | The crystal structure of the cyclic phosphodiesterase (CPDase) from Arabidopsis thaliana, an enzyme involved in the tRNA splicing pathway, was determined at 2.5 A resolution. CPDase hydrolyzes ADP-ribose 1",2"-cyclic phosphate (Appr>p), a product of the tRNA splicing reaction, to the monoester ADP-ribose 1"-phosphate (Appr-1"p). The 181 amino acid protein shows a novel, bilobal arrangement of two alphabeta modules. Each lobe consists of two alpha-helices on the outer side of the molecule, framing a three- or four-stranded antiparallel beta-sheet in the core of the protein. The active site is formed at the interface of the two beta-sheets in a water-filled cavity involving residues from two H-X-T/S-X motifs. This previously noticed motif participates in coordination of a sulfate ion. A solvent-exposed surface loop (residues 100-115) is very likely to play a flap-like role, opening and closing the active site. Based on the crystal structure and on recent mutagenesis studies of a homologous CPDase from Saccharomyces cerevisiae, we propose an enzymatic mechanism that employs the nucleophilic attack of a water molecule activated by one of the active site histidines. |
==About this Structure== | ==About this Structure== | ||
| - | 1FSI is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Arabidopsis_thaliana Arabidopsis thaliana] with SO4 as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1FSI is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Arabidopsis_thaliana Arabidopsis thaliana] with <scene name='pdbligand=SO4:'>SO4</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1FSI OCA]. |
==Reference== | ==Reference== | ||
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[[Category: appr>p]] | [[Category: appr>p]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:42:08 2008'' |
Revision as of 10:42, 21 February 2008
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CRYSTAL STRUCTURE OF CYCLIC NUCLEOTIDE PHOSPHODIESTERASE OF APPR>P FROM ARABIDOPSIS THALIANA
Overview
The crystal structure of the cyclic phosphodiesterase (CPDase) from Arabidopsis thaliana, an enzyme involved in the tRNA splicing pathway, was determined at 2.5 A resolution. CPDase hydrolyzes ADP-ribose 1",2"-cyclic phosphate (Appr>p), a product of the tRNA splicing reaction, to the monoester ADP-ribose 1"-phosphate (Appr-1"p). The 181 amino acid protein shows a novel, bilobal arrangement of two alphabeta modules. Each lobe consists of two alpha-helices on the outer side of the molecule, framing a three- or four-stranded antiparallel beta-sheet in the core of the protein. The active site is formed at the interface of the two beta-sheets in a water-filled cavity involving residues from two H-X-T/S-X motifs. This previously noticed motif participates in coordination of a sulfate ion. A solvent-exposed surface loop (residues 100-115) is very likely to play a flap-like role, opening and closing the active site. Based on the crystal structure and on recent mutagenesis studies of a homologous CPDase from Saccharomyces cerevisiae, we propose an enzymatic mechanism that employs the nucleophilic attack of a water molecule activated by one of the active site histidines.
About this Structure
1FSI is a Single protein structure of sequence from Arabidopsis thaliana with as ligand. Full crystallographic information is available from OCA.
Reference
Structure and mechanism of activity of the cyclic phosphodiesterase of Appr>p, a product of the tRNA splicing reaction., Hofmann A, Zdanov A, Genschik P, Ruvinov S, Filipowicz W, Wlodawer A, EMBO J. 2000 Nov 15;19(22):6207-17. PMID:11080166[[Category: 2-cyclic phosphate]][[Category: adp-ribose 1]] [[Category: appr>p]]
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