4HFK

Crystal structure of the type VI effector-immunity complex Tae4-Tai4 from Enterobacter cloacae


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.203 
  • R-Value Work: 0.157 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of the type VI effector-immunity complex (Tae4-Tai4) provides novel insights into the inhibition mechanism of the effector by its immunity protein.

Zhang, H.Zhang, H.Gao, Z.Q.Wang, W.J.Liu, G.F.Xu, J.H.Su, X.D.Dong, Y.H.

(2013) J.Biol.Chem. 288: 5928-5939

  • DOI: 10.1074/jbc.M112.434357
  • Primary Citation of Related Structures:  4HFF, 4HFL

  • PubMed Abstract: 
  • The type VI secretion system (T6SS), a multisubunit needle-like apparatus, has recently been found to play a role in interspecies interactions. The gram-negative bacteria harboring T6SS (donor) deliver the effectors into their neighboring cells (reci ...

    The type VI secretion system (T6SS), a multisubunit needle-like apparatus, has recently been found to play a role in interspecies interactions. The gram-negative bacteria harboring T6SS (donor) deliver the effectors into their neighboring cells (recipient) to kill them. Meanwhile, the cognate immunity proteins were employed to protect the donor cells against the toxic effectors. Tae4 (type VI amidase effector 4) and Tai4 (type VI amidase immunity 4) are newly identified T6SS effector-immunity pairs. Here, we report the crystal structures of Tae4 from Enterobacter cloacae and Tae4-Tai4 complexes from both E. cloacae and Salmonella typhimurium. Tae4 acts as a DL-endopeptidase and displays a typical N1pC/P60 domain. Unlike Tsi1 (type VI secretion immunity 1), Tai4 is an all-helical protein and forms a dimer in solution. The small angle x-ray scattering study combined with the analytical ultracentrifugation reveal that the Tae4-Tai4 complex is a compact heterotetramer that consists of a Tai4 dimer and two Tae4 molecules in solution. Structure-based mutational analysis of the Tae4-Tai4 interface shows that a helix (α3) of one subunit in dimeric Tai4 plays a major role in binding of Tae4, whereas a protruding loop (L4) in the other subunit is mainly responsible for inhibiting Tae4 activity. The inhibition process requires collaboration between the Tai4 dimer. These results reveal a novel and unique inhibition mechanism in effector-immunity pairs and suggest a new strategy to develop antipathogen drugs.


    Organizational Affiliation

    State Key Laboratory of Protein and Plant Gene Research, School of Life Sciences, Peking University, No. 5 Yiheyuan Road, Beijing 100871, China.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Putative cytoplasmic protein
A, C
176Enterobacter cloacae subsp. cloacae (strain ATCC 13047 / DSM 30054 / NBRC 13535 / NCDC 279-56)N/A
Find proteins for A0A0H3CIJ2 (Enterobacter cloacae subsp. cloacae (strain ATCC 13047 / DSM 30054 / NBRC 13535 / NCDC 279-56))
Go to UniProtKB:  A0A0H3CIJ2
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Putative uncharacterized protein
B, D
105Enterobacter cloacae subsp. cloacae (strain ATCC 13047 / DSM 30054 / NBRC 13535 / NCDC 279-56)N/A
Find proteins for A0A0H3CIX8 (Enterobacter cloacae subsp. cloacae (strain ATCC 13047 / DSM 30054 / NBRC 13535 / NCDC 279-56))
Go to UniProtKB:  A0A0H3CIX8
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
SO4
Query on SO4

Download SDF File 
Download CCD File 
B
SULFATE ION
O4 S
QAOWNCQODCNURD-UHFFFAOYSA-L
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.1 Å
  • R-Value Free: 0.203 
  • R-Value Work: 0.157 
  • Space Group: C 1 2 1
Unit Cell:
Length (Å)Angle (°)
a = 91.342α = 90.00
b = 138.144β = 127.89
c = 64.462γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data reduction
MAR345data collection
HKL-2000data scaling
PHASERphasing
PHENIXrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2013-01-16
    Type: Initial release
  • Version 1.1: 2013-07-24
    Type: Database references
  • Version 1.2: 2017-11-15
    Type: Refinement description