1e3h
From Proteopedia
(New page: 200px<br /><applet load="1e3h" size="450" color="white" frame="true" align="right" spinBox="true" caption="1e3h, resolution 2.60Å" /> '''SEMET DERIVATIVE OF ...) |
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| - | [[Image:1e3h.jpg|left|200px]]<br /><applet load="1e3h" size=" | + | [[Image:1e3h.jpg|left|200px]]<br /><applet load="1e3h" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1e3h, resolution 2.60Å" /> | caption="1e3h, resolution 2.60Å" /> | ||
'''SEMET DERIVATIVE OF STREPTOMYCES ANTIBIOTICUS PNPASE/GPSI ENZYME'''<br /> | '''SEMET DERIVATIVE OF STREPTOMYCES ANTIBIOTICUS PNPASE/GPSI ENZYME'''<br /> | ||
==Overview== | ==Overview== | ||
| - | BACKGROUND: Polynucleotide phosphorylase (PNPase) is a polyribonucleotide | + | BACKGROUND: Polynucleotide phosphorylase (PNPase) is a polyribonucleotide nucleotidyl transferase (E.C.2.7.7.8) that degrades mRNA in prokaryotes. Streptomyces antibioticus PNPase also assays as a guanosine 3'-diphosphate 5'-triphosphate (pppGpp) synthetase (E.C.2.7.6.5). It may function to coordinate changes in mRNA lifetimes with pppGpp levels during the Streptomyces lifecycle. RESULTS: The structure of S. antibioticus PNPase without bound RNA but with the phosphate analog tungstate bound at the PNPase catalytic sites was determined by X-ray crystallography and shows a trimeric multidomain protein with a central channel. The structural core has a novel duplicated architecture formed by association of two homologous domains. The tungstate derivative structure reveals the PNPase active site in the second of these core domains. Structure-based sequence analysis suggests that the pppGpp synthetase active site is located in the first core domain. CONCLUSIONS: This is the first structure of a PNPase and shows the structural basis for the trimer assembly, the arrangement of accessory RNA binding domains, and the likely catalytic residues of the PNPase active site. A possible function of the trimer channel is as a contribution to both the processivity of degradation and the regulation of PNPase action by RNA structural elements. |
==About this Structure== | ==About this Structure== | ||
| - | 1E3H is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Streptomyces_antibioticus Streptomyces antibioticus] with SO4 as [http://en.wikipedia.org/wiki/ligand ligand]. Full crystallographic information is available from [http:// | + | 1E3H is a [http://en.wikipedia.org/wiki/Single_protein Single protein] structure of sequence from [http://en.wikipedia.org/wiki/Streptomyces_antibioticus Streptomyces antibioticus] 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=1E3H OCA]. |
==Reference== | ==Reference== | ||
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[[Category: Single protein]] | [[Category: Single protein]] | ||
[[Category: Streptomyces antibioticus]] | [[Category: Streptomyces antibioticus]] | ||
| - | [[Category: Jones, G | + | [[Category: Jones, G H.]] |
| - | [[Category: Luisi, B | + | [[Category: Luisi, B F.]] |
| - | [[Category: Symmons, M | + | [[Category: Symmons, M F.]] |
[[Category: SO4]] | [[Category: SO4]] | ||
[[Category: atp:gtp diphosphotransferase]] | [[Category: atp:gtp diphosphotransferase]] | ||
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[[Category: rna processing]] | [[Category: rna processing]] | ||
| - | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 12:23:21 2008'' |
Revision as of 10:23, 21 February 2008
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SEMET DERIVATIVE OF STREPTOMYCES ANTIBIOTICUS PNPASE/GPSI ENZYME
Overview
BACKGROUND: Polynucleotide phosphorylase (PNPase) is a polyribonucleotide nucleotidyl transferase (E.C.2.7.7.8) that degrades mRNA in prokaryotes. Streptomyces antibioticus PNPase also assays as a guanosine 3'-diphosphate 5'-triphosphate (pppGpp) synthetase (E.C.2.7.6.5). It may function to coordinate changes in mRNA lifetimes with pppGpp levels during the Streptomyces lifecycle. RESULTS: The structure of S. antibioticus PNPase without bound RNA but with the phosphate analog tungstate bound at the PNPase catalytic sites was determined by X-ray crystallography and shows a trimeric multidomain protein with a central channel. The structural core has a novel duplicated architecture formed by association of two homologous domains. The tungstate derivative structure reveals the PNPase active site in the second of these core domains. Structure-based sequence analysis suggests that the pppGpp synthetase active site is located in the first core domain. CONCLUSIONS: This is the first structure of a PNPase and shows the structural basis for the trimer assembly, the arrangement of accessory RNA binding domains, and the likely catalytic residues of the PNPase active site. A possible function of the trimer channel is as a contribution to both the processivity of degradation and the regulation of PNPase action by RNA structural elements.
About this Structure
1E3H is a Single protein structure of sequence from Streptomyces antibioticus with as ligand. Full crystallographic information is available from OCA.
Reference
A duplicated fold is the structural basis for polynucleotide phosphorylase catalytic activity, processivity, and regulation., Symmons MF, Jones GH, Luisi BF, Structure. 2000 Nov 15;8(11):1215-26. PMID:11080643
Page seeded by OCA on Thu Feb 21 12:23:21 2008
