Crystal structure of Pyrococcus furiosus PbaA, an archaeal homolog of proteasome-assembly chaperone

Experimental Data Snapshot

  • Resolution: 2.25 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.196 
  • R-Value Observed: 0.198 

wwPDB Validation   3D Report Full Report

This is version 1.3 of the entry. See complete history


Crystal structure of archaeal homolog of proteasome-assembly chaperone PbaA

Sikdar, A.Satoh, T.Kawasaki, M.Kato, K.

(2014) Biochem Biophys Res Commun 453: 493-497

  • DOI: https://doi.org/10.1016/j.bbrc.2014.09.114
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 

    Formation of the eukaryotic proteasome is not a spontaneous process but a highly ordered process assisted by several assembly chaperones. In contrast, archaeal proteasome subunits can spontaneously assemble into an active form. Recent bioinformatic analysis identified the proteasome-assembly chaperone-like proteins, PbaA and PbaB, in archaea. Our previous study showed that the PbaB homotetramer functions as a proteasome activator through its tentacle-like C-terminal segments. However, a functional role of the other homolog PbaA has remained elusive. Here we determined the 2.25-Å resolution structure of PbaA, illustrating its disparate tertiary and quaternary structures compared with PbaB. PbaA forms a homopentamer in which the C-terminal segments, with a putative proteasome-activating motif, are packed against the core. These findings offer deeper insights into the molecular evolution relationships between the proteasome-assembly chaperones and the proteasome activators.

  • Organizational Affiliation

    School of Physical Science, The Graduate University for Advanced Studies, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan; Okazaki Institute for Integrative Bioscience and Institute for Molecular Science, National Institutes of Natural Sciences, 5-1 Higashiyama, Myodaiji, Okazaki, Aichi 444-8787, Japan; Graduate School of Pharmaceutical Sciences, Nagoya City University, 3-1 Tanabe-dori, Mizuho-ku, Nagoya 467-8603, Japan.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Uncharacterized protein
A, B, C, D, E
245Pyrococcus furiosus DSM 3638Mutation(s): 0 
Gene Names: PF0015
Find proteins for Q8U4Q9 (Pyrococcus furiosus (strain ATCC 43587 / DSM 3638 / JCM 8422 / Vc1))
Explore Q8U4Q9 
Go to UniProtKB:  Q8U4Q9
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ8U4Q9
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 2.25 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.196 
  • R-Value Observed: 0.198 
  • Space Group: C 2 2 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 111.373α = 90
b = 155.187β = 90
c = 172.004γ = 90
Software Package:
Software NamePurpose
HKL-2000data collection
DENZOdata reduction
SCALEPACKdata scaling

Structure Validation

View Full Validation Report

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2014-10-08
    Type: Initial release
  • Version 1.1: 2014-10-15
    Changes: Database references
  • Version 1.2: 2014-12-31
    Changes: Database references
  • Version 1.3: 2024-03-20
    Changes: Data collection, Database references, Refinement description