3Q4H

Crystal structure of the Mycobacterium smegmatis EsxGH complex (MSMEG_0620-MSMEG_0621)


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.70 Å
  • R-Value Free: 0.268 
  • R-Value Work: 0.207 
  • R-Value Observed: 0.210 

wwPDB Validation   3D Report Full Report


This is version 1.3 of the entry. See complete history


Literature

Heterologous expression of mycobacterial Esx complexes in Escherichia coli for structural studies is facilitated by the use of maltose binding protein fusions.

Arbing, M.A.Chan, S.Harris, L.Kuo, E.Zhou, T.T.Ahn, C.J.Nguyen, L.He, Q.Lu, J.Menchavez, P.T.Shin, A.Holton, T.Sawaya, M.R.Cascio, D.Eisenberg, D.

(2013) PLoS One 8: e81753-e81753

  • DOI: 10.1371/journal.pone.0081753
  • Primary Citation of Related Structures:  
    3Q4H, 4I0X, 4GZR, 3OGI

  • PubMed Abstract: 
  • The expression of heteroligomeric protein complexes for structural studies often requires a special coexpression strategy. The reason is that the solubility and proper folding of each subunit of the complex requires physical association with other su ...

    The expression of heteroligomeric protein complexes for structural studies often requires a special coexpression strategy. The reason is that the solubility and proper folding of each subunit of the complex requires physical association with other subunits of the complex. The genomes of pathogenic mycobacteria encode many small protein complexes, implicated in bacterial fitness and pathogenicity, whose characterization may be further complicated by insolubility upon expression in Escherichia coli, the most common heterologous protein expression host. As protein fusions have been shown to dramatically affect the solubility of the proteins to which they are fused, we evaluated the ability of maltose binding protein fusions to produce mycobacterial Esx protein complexes. A single plasmid expression strategy using an N-terminal maltose binding protein fusion to the CFP-10 homolog proved effective in producing soluble Esx protein complexes, as determined by a small-scale expression and affinity purification screen, and coupled with intracellular proteolytic cleavage of the maltose binding protein moiety produced protein complexes of sufficient purity for structural studies. In comparison, the expression of complexes with hexahistidine affinity tags alone on the CFP-10 subunits failed to express in amounts sufficient for biochemical characterization. Using this strategy, six mycobacterial Esx complexes were expressed, purified to homogeneity, and subjected to crystallization screening and the crystal structures of the Mycobacterium abscessus EsxEF, M. smegmatis EsxGH, and M. tuberculosis EsxOP complexes were determined. Maltose binding protein fusions are thus an effective method for production of Esx complexes and this strategy may be applicable for production of other protein complexes.


    Organizational Affiliation

    UCLA-DOE Institute for Genomics and Proteomics, University of California Los Angeles, Los Angeles, California, United States of America.



Macromolecules
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Pe family proteinAC98Mycolicibacterium smegmatis MC2 155Mutation(s): 0 
Gene Names: MSMEG_0620esxGMSMEI_0604
Find proteins for A0QQ43 (Mycolicibacterium smegmatis (strain ATCC 700084 / mc(2)155))
Explore A0QQ43 
Go to UniProtKB:  A0QQ43
Protein Feature View
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  Structure
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Low molecular weight protein antigen 7BD102Mycolicibacterium smegmatis MC2 155Mutation(s): 0 
Gene Names: MSMEG_0621esxHMSMEI_0605
Find proteins for A0QQ44 (Mycolicibacterium smegmatis (strain ATCC 700084 / mc(2)155))
Explore A0QQ44 
Go to UniProtKB:  A0QQ44
Protein Feature View
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  • Reference Sequence
Small Molecules
Modified Residues  1 Unique
IDChainsTypeFormula2D DiagramParent
MSE
Query on MSE
A,CL-PEPTIDE LINKINGC5 H11 N O2 SeMET
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.70 Å
  • R-Value Free: 0.268 
  • R-Value Work: 0.207 
  • R-Value Observed: 0.210 
  • Space Group: P 63
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 105.598α = 90
b = 105.598β = 90
c = 71.328γ = 120
Software Package:
Software NamePurpose
ADSCdata collection
SHELXmodel building
REFMACrefinement
DENZOdata reduction
SCALEPACKdata scaling
SHELXphasing

Structure Validation

View Full Validation Report



Entry History 

Revision History 

  • Version 1.0: 2011-01-26
    Type: Initial release
  • Version 1.1: 2011-07-13
    Changes: Version format compliance
  • Version 1.2: 2013-09-25
    Changes: Derived calculations
  • Version 1.3: 2014-05-14
    Changes: Database references