5LFQ

Crystal Structure of the Bacterial Proteasome Activator Bpa of Mycobacterium tuberculosis (space group P3)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.503 Å
  • R-Value Free: 0.301 
  • R-Value Work: 0.242 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Structural Analysis of the Bacterial Proteasome Activator Bpa in Complex with the 20S Proteasome.

Bolten, M.Delley, C.L.Leibundgut, M.Boehringer, D.Ban, N.Weber-Ban, E.

(2016) Structure 24: 2138-2151

  • DOI: 10.1016/j.str.2016.10.008
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Mycobacterium tuberculosis harbors proteasomes that recruit substrates for degradation through an ubiquitin-like modification pathway. Recently, a non-ATPase activator termed Bpa (bacterial proteasome activator) was shown to support an alternate prot ...

    Mycobacterium tuberculosis harbors proteasomes that recruit substrates for degradation through an ubiquitin-like modification pathway. Recently, a non-ATPase activator termed Bpa (bacterial proteasome activator) was shown to support an alternate proteasomal degradation pathway. Here, we present the cryo-electron microscopy (cryo-EM) structure of Bpa in complex with the 20S core particle (CP). For docking into the cryo-EM density, we solved the X-ray structure of Bpa, showing that it forms tight four-helix bundles arranged into a 12-membered ring with a 40 Å wide central pore and the C-terminal helix of each protomer protruding from the ring. The Bpa model was fitted into the cryo-EM map of the Bpa-CP complex, revealing its architecture and striking symmetry mismatch. The Bpa-CP interface was resolved to 3.5 Å, showing the interactions between the C-terminal GQYL motif of Bpa and the proteasome α-rings. This docking mode is related to the one observed for eukaryotic activators with features specific to the bacterial complex.


    Organizational Affiliation

    ETH Zurich, Institute of Molecular Biology & Biophysics, 8093 Zurich, Switzerland.,ETH Zurich, Institute of Molecular Biology & Biophysics, 8093 Zurich, Switzerland. Electronic address: eilika@mol.biol.ethz.ch.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Bacterial proteasome activator
A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P
131Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv)Mutation(s): 0 
Gene Names: bpa
Find proteins for P9WKX3 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Go to UniProtKB:  P9WKX3
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P
L-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 3.503 Å
  • R-Value Free: 0.301 
  • R-Value Work: 0.242 
  • Space Group: P 3
Unit Cell:
Length (Å)Angle (°)
a = 100.854α = 90.00
b = 100.854β = 90.00
c = 207.433γ = 120.00
Software Package:
Software NamePurpose
Aimlessdata scaling
PDB_EXTRACTdata extraction
XDSdata reduction
PHASERphasing
PHENIXrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2016-11-23
    Type: Initial release
  • Version 1.1: 2016-12-14
    Type: Database references