1j2q
From Proteopedia
(New page: 200px<br /><applet load="1j2q" size="450" color="white" frame="true" align="right" spinBox="true" caption="1j2q, resolution 2.83Å" /> '''20S proteasome in co...) |
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- | [[Image:1j2q.gif|left|200px]]<br /><applet load="1j2q" size=" | + | [[Image:1j2q.gif|left|200px]]<br /><applet load="1j2q" size="350" color="white" frame="true" align="right" spinBox="true" |
caption="1j2q, resolution 2.83Å" /> | caption="1j2q, resolution 2.83Å" /> | ||
'''20S proteasome in complex with calpain-Inhibitor I from archaeoglobus fulgidus'''<br /> | '''20S proteasome in complex with calpain-Inhibitor I from archaeoglobus fulgidus'''<br /> | ||
==Overview== | ==Overview== | ||
- | The 20S proteasome (core particle, CP) is a multifunctional protease | + | The 20S proteasome (core particle, CP) is a multifunctional protease complex and composed of four heptameric subunit rings arranged in a hollow, barrel-shaped structure. Here, we report the crystal structure of the CP from Archaeoglobus fulgidus at 2.25A resolution. The analysis of the structure of early and late assembly intermediates of this CP gives new insights in the maturation of archaebacterial CPs and indicates similarities to assembly intermediates observed in eukaryotes. We also show a striking difference in mechanism and regulation of substrate access between eukaryotic and archaebacterial 20S proteasomes. While eukaryotic CPs are auto-inhibited by the N-terminal tails of the outer alpha-ring by imposing topological closure with a characteristic sequence motif (YDR-motif) and show regulatory gating this segment is disordered in the CP and differently structured in the alpha(7)-sub-complex of A.fulgidus leaving a pore leading into the particle with a diameter of 13A. Mutagenesis and functional studies indicate the absence of regulatory gating in the archaeal 20S proteasome. |
==About this Structure== | ==About this Structure== | ||
- | 1J2Q is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Archaeoglobus_fulgidus Archaeoglobus fulgidus] with CIB as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Proteasome_endopeptidase_complex Proteasome endopeptidase complex], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.25.1 3.4.25.1] Full crystallographic information is available from [http:// | + | 1J2Q is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Archaeoglobus_fulgidus Archaeoglobus fulgidus] with <scene name='pdbligand=CIB:'>CIB</scene> as [http://en.wikipedia.org/wiki/ligand ligand]. Active as [http://en.wikipedia.org/wiki/Proteasome_endopeptidase_complex Proteasome endopeptidase complex], with EC number [http://www.brenda-enzymes.info/php/result_flat.php4?ecno=3.4.25.1 3.4.25.1] Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1J2Q OCA]. |
==Reference== | ==Reference== | ||
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[[Category: ubiquitin]] | [[Category: ubiquitin]] | ||
- | ''Page seeded by [http:// | + | ''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 13:18:23 2008'' |
Revision as of 11:18, 21 February 2008
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20S proteasome in complex with calpain-Inhibitor I from archaeoglobus fulgidus
Overview
The 20S proteasome (core particle, CP) is a multifunctional protease complex and composed of four heptameric subunit rings arranged in a hollow, barrel-shaped structure. Here, we report the crystal structure of the CP from Archaeoglobus fulgidus at 2.25A resolution. The analysis of the structure of early and late assembly intermediates of this CP gives new insights in the maturation of archaebacterial CPs and indicates similarities to assembly intermediates observed in eukaryotes. We also show a striking difference in mechanism and regulation of substrate access between eukaryotic and archaebacterial 20S proteasomes. While eukaryotic CPs are auto-inhibited by the N-terminal tails of the outer alpha-ring by imposing topological closure with a characteristic sequence motif (YDR-motif) and show regulatory gating this segment is disordered in the CP and differently structured in the alpha(7)-sub-complex of A.fulgidus leaving a pore leading into the particle with a diameter of 13A. Mutagenesis and functional studies indicate the absence of regulatory gating in the archaeal 20S proteasome.
About this Structure
1J2Q is a Protein complex structure of sequences from Archaeoglobus fulgidus with as ligand. Active as Proteasome endopeptidase complex, with EC number 3.4.25.1 Full crystallographic information is available from OCA.
Reference
Investigations on the maturation and regulation of archaebacterial proteasomes., Groll M, Brandstetter H, Bartunik H, Bourenkow G, Huber R, J Mol Biol. 2003 Mar 14;327(1):75-83. PMID:12614609
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