3J83

Heptameric EspB Rosetta model guided by EM density


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 30.0 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Structure of EspB from the ESX-1 Type VII Secretion System and Insights into its Export Mechanism.

Solomonson, M.Setiaputra, D.Makepeace, K.A.Lameignere, E.Petrotchenko, E.V.Conrady, D.G.Bergeron, J.R.Vuckovic, M.DiMaio, F.Borchers, C.H.Yip, C.K.Strynadka, N.C.

(2015) Structure 23: 571-583

  • DOI: https://doi.org/10.1016/j.str.2015.01.002
  • Primary Citation of Related Structures:  
    3J83, 4WJ1, 4WJ2

  • PubMed Abstract: 

    Mycobacterium tuberculosis (Mtb) uses the ESX-1 type VII secretion system to export virulence proteins across its lipid-rich cell wall, which helps permeabilize the host's macrophage phagosomal membrane, facilitating the escape and cell-to-cell spread of Mtb. ESX-1 membranolytic activity depends on a set of specialized secreted Esp proteins, the structure and specific roles of which are not currently understood. Here, we report the X-ray and electron microscopic structures of the ESX-1-secreted EspB. We demonstrate that EspB adopts a PE/PPE-like fold that mediates oligomerization with apparent heptameric symmetry, generating a barrel-shaped structure with a central pore that we propose contributes to the macrophage killing functions of EspB. Our structural data also reveal unexpected direct interactions between the EspB bipartite secretion signal sequence elements that form a unified aromatic surface. These findings provide insight into how specialized proteins encoded within the ESX-1 locus are targeted for secretion, and for the first time indicate an oligomerization-dependent role for Esp virulence factors.


  • Organizational Affiliation

    Department of Biochemistry and Molecular Biology, Life Sciences Centre, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3, Canada; Centre for Blood Research, Life Sciences Centre, The University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T 1Z3, Canada.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
ESX-1 secretion-associated protein EspB
A, B, C, D, E
A, B, C, D, E, F, G
371Mycobacterium tuberculosis H37RvMutation(s): 0 
Gene Names: espBmtb48Rv3881cMTV027.16c
UniProt
Find proteins for P9WJD9 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Explore P9WJD9 
Go to UniProtKB:  P9WJD9
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP9WJD9
Sequence Annotations
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 30.0 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 
EM Software:
TaskSoftware PackageVersion
RECONSTRUCTIONEMAN2
RECONSTRUCTIONSPIDER

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2015-03-11
    Type: Initial release
  • Version 1.1: 2015-03-18
    Changes: Database references
  • Version 1.2: 2018-07-18
    Changes: Data collection
  • Version 1.3: 2024-02-21
    Changes: Data collection, Database references, Refinement description