4KXR

Structure of the Mycobacterium tuberculosis type VII secretion system chaperone EspG5 in complex with PE25-PPE41 dimer


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.244 
  • R-Value Work: 0.194 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Structure of the Mycobacterium tuberculosis type VII secretion system chaperone EspG5 in complex with PE25-PPE41 dimer.

Korotkova, N.Freire, D.Phan, T.H.Ummels, R.Creekmore, C.C.Evans, T.J.Wilmanns, M.Bitter, W.Parret, A.H.Houben, E.N.Korotkov, K.V.

(2014) Mol.Microbiol. 94: 367-382

  • DOI: 10.1111/mmi.12770

  • PubMed Abstract: 
  • The growth or virulence of Mycobacterium tuberculosis bacilli depends on homologous type VII secretion systems, ESX-1, ESX-3 and ESX-5, which export a number of protein effectors across membranes to the bacterial surface and environment. PE and PPE p ...

    The growth or virulence of Mycobacterium tuberculosis bacilli depends on homologous type VII secretion systems, ESX-1, ESX-3 and ESX-5, which export a number of protein effectors across membranes to the bacterial surface and environment. PE and PPE proteins represent two large families of highly polymorphic proteins that are secreted by these ESX systems. Recently, it was shown that these proteins require system-specific cytoplasmic chaperones for secretion. Here, we report the crystal structure of M. tuberculosis ESX-5-secreted PE25-PPE41 heterodimer in complex with the cytoplasmic chaperone EspG(5). EspG(5) represents a novel fold that is unrelated to previously characterized secretion chaperones. Functional analysis of the EspG(5) -binding region uncovered a hydrophobic patch on PPE41 that promotes dimer aggregation, and the chaperone effectively abolishes this process. We show that PPE41 contains a characteristic chaperone-binding sequence, the hh motif, which is highly conserved among ESX-1-, ESX-3- and ESX-5-specific PPE proteins. Disrupting the interaction between EspG(5) and three different PPE target proteins by introducing different point mutations generally affected protein secretion. We further demonstrate that the EspG(5) chaperone plays an important role in the ESX secretion mechanism by keeping aggregation-prone PE-PPE proteins in their soluble state.


    Organizational Affiliation

    Department of Molecular & Cellular Biochemistry, University of Kentucky, Lexington, KY, 40536, USA; Center for Structural Biology, University of Kentucky, Lexington, KY, 40536, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
PE25
A
101Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv)Mutation(s): 0 
Gene Names: PE25
Find proteins for I6X486 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Go to UniProtKB:  I6X486
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
PPE41
B
194Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv)Mutation(s): 0 
Gene Names: PPE41
Find proteins for Q79FE1 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Go to UniProtKB:  Q79FE1
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
EspG5
C
300Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv)Mutation(s): 0 
Gene Names: espG5
Find proteins for O53943 (Mycobacterium tuberculosis (strain ATCC 25618 / H37Rv))
Go to UniProtKB:  O53943
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.6 Å
  • R-Value Free: 0.244 
  • R-Value Work: 0.194 
  • Space Group: P 61 2 2
Unit Cell:
Length (Å)Angle (°)
a = 139.100α = 90.00
b = 139.100β = 90.00
c = 171.010γ = 120.00
Software Package:
Software NamePurpose
SERGUIdata collection
PDB_EXTRACTdata extraction
XDSdata reduction
PHASERphasing
XSCALEdata scaling
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2014-05-28
    Type: Initial release
  • Version 1.1: 2014-08-27
    Type: Database references
  • Version 1.2: 2014-09-03
    Type: Database references
  • Version 1.3: 2014-10-22
    Type: Database references