4W4L

Crystal structure of EspG5 in complex with PE25 and PPE41 from the ESX-5 type VII secretion system of M. tuberculosis


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.45 Å
  • R-Value Free: 0.230 
  • R-Value Work: 0.202 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Structure of a PE-PPE-EspG complex from Mycobacterium tuberculosis reveals molecular specificity of ESX protein secretion.

Ekiert, D.C.Cox, J.S.

(2014) Proc.Natl.Acad.Sci.USA 111: 14758-14763

  • DOI: 10.1073/pnas.1409345111
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Nearly 10% of the coding capacity of the Mycobacterium tuberculosis genome is devoted to two highly expanded and enigmatic protein families called PE and PPE, some of which are important virulence/immunogenicity factors and are secreted during infect ...

    Nearly 10% of the coding capacity of the Mycobacterium tuberculosis genome is devoted to two highly expanded and enigmatic protein families called PE and PPE, some of which are important virulence/immunogenicity factors and are secreted during infection via a unique alternative secretory system termed "type VII." How PE-PPE proteins function during infection and how they are translocated to the bacterial surface through the five distinct type VII secretion systems [ESAT-6 secretion system (ESX)] of M. tuberculosis is poorly understood. Here, we report the crystal structure of a PE-PPE heterodimer bound to ESX secretion-associated protein G (EspG), which adopts a novel fold. This PE-PPE-EspG complex, along with structures of two additional EspGs, suggests that EspG acts as an adaptor that recognizes specific PE-PPE protein complexes via extensive interactions with PPE domains, and delivers them to ESX machinery for secretion. Surprisingly, secretion of most PE-PPE proteins in M. tuberculosis is likely mediated by EspG from the ESX-5 system, underscoring the importance of ESX-5 in mycobacterial pathogenesis. Moreover, our results indicate that PE-PPE domains function as cis-acting targeting sequences that are read out by EspGs, revealing the molecular specificity for secretion through distinct ESX pathways.


    Organizational Affiliation

    Department of Microbiology and Immunology, University of California, San Francisco, CA 94143 damian.ekiert@ucsf.edu jeffery.cox@ucsf.edu.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PE family protein PE25
A
109Mycobacterium tuberculosis (strain ATCC 35801 / TMC 107 / Erdman)Mutation(s): 0 
Gene Names: PE25
Find proteins for A0A0H3LBR3 (Mycobacterium tuberculosis (strain ATCC 35801 / TMC 107 / Erdman))
Go to UniProtKB:  A0A0H3LBR3
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
PPE family protein PPE41
B
174Mycobacterium tuberculosis (strain ATCC 35801 / TMC 107 / Erdman)Mutation(s): 0 
Gene Names: PPE41
Find proteins for A0A0H3LBN6 (Mycobacterium tuberculosis (strain ATCC 35801 / TMC 107 / Erdman))
Go to UniProtKB:  A0A0H3LBN6
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
EspG5
C
314Mycobacterium tuberculosis (strain ATCC 35801 / TMC 107 / Erdman)Mutation(s): 0 
Find proteins for A0A0H3LAM1 (Mycobacterium tuberculosis (strain ATCC 35801 / TMC 107 / Erdman))
Go to UniProtKB:  A0A0H3LAM1
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
EDO
Query on EDO

Download SDF File 
Download CCD File 
B
1,2-ETHANEDIOL
ETHYLENE GLYCOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.45 Å
  • R-Value Free: 0.230 
  • R-Value Work: 0.202 
  • Space Group: P 61 2 2
Unit Cell:
Length (Å)Angle (°)
a = 138.640α = 90.00
b = 138.640β = 90.00
c = 169.680γ = 120.00
Software Package:
Software NamePurpose
XDSdata reduction
PHENIXrefinement
Blu-Icedata collection
PHASERphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute Of Allergy and Infectious DiseasesUnited StatesR01AI081727
Damon Runyon Cancer Research FoundationUnited KingdomDRG-2140-12

Revision History 

  • Version 1.0: 2014-10-01
    Type: Initial release
  • Version 1.1: 2014-10-15
    Type: Database references
  • Version 1.2: 2014-10-29
    Type: Database references
  • Version 1.3: 2017-09-27
    Type: Author supporting evidence, Database references, Derived calculations, Other, Refinement description, Source and taxonomy, Structure summary