1J2P

alpha-ring from the proteasome from archaeoglobus fulgidus

Summary for 1J2P

• Entry DOI: 10.2210/pdb1j2p/pdb
• Related: 1J2Q
• Descriptor: Proteasome alpha subunit (2 entities in total)
• Functional Keywords: proteasome, alpha-ring, hydrolase
• Biological source: Archaeoglobus fulgidus
• Cellular location: Cytoplasm (By similarity): O29760
• Total number of polymer chains: 7
• Total formula weight: 193858.19

Authors

Groll, M.,Brandstetter, H.,Bartunik, H.,Bourenkow, G.,Huber, R. (deposition date: 2003-01-08, release date: 2003-03-18, Last modification date: 2024-04-03)

Primary citation

Groll, M.,Brandstetter, H.,Bartunik, H.,Bourenkow, G.,Huber, R.
Investigations on the Maturation and Regulation of Archaebacterial Proteasomes
J.MOL.BIOL., 327:75-83, 2003

PubMed Abstract: 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.

PubMed: 12614609
DOI: 10.1016/S0022-2836(03)00080-9

Experimental method

X-RAY DIFFRACTION (2.6 Å)