5MWN

Structure of the EAEC T6SS component TssK N-terminal domain in complex with llama nanobodies nbK18 and nbK27


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.199 

wwPDB Validation 3D Report Full Report


This is version 1.4 of the entry. See complete history

Literature

Type VI secretion TssK baseplate protein exhibits structural similarity with phage receptor-binding proteins and evolved to bind the membrane complex.

Nguyen, V.S.Logger, L.Spinelli, S.Legrand, P.Huyen Pham, T.T.Nhung Trinh, T.T.Cherrak, Y.Zoued, A.Desmyter, A.Durand, E.Roussel, A.Kellenberger, C.Cascales, E.Cambillau, C.

(2017) Nat Microbiol 2: 17103-17103

  • DOI: 10.1038/nmicrobiol.2017.103
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The type VI secretion system (T6SS) is a multiprotein machine widespread in Gram-negative bacteria that delivers toxins into both eukaryotic and prokaryotic cells. The mechanism of action of the T6SS is comparable to that of contractile myophages. Th ...

    The type VI secretion system (T6SS) is a multiprotein machine widespread in Gram-negative bacteria that delivers toxins into both eukaryotic and prokaryotic cells. The mechanism of action of the T6SS is comparable to that of contractile myophages. The T6SS builds a tail-like structure made of an inner tube wrapped by a sheath, assembled under an extended conformation. Contraction of the sheath propels the inner tube towards the target cell. The T6SS tail is assembled on a platform-the baseplate-which is functionally similar to bacteriophage baseplates. In addition, the baseplate docks the tail to a trans-envelope membrane complex that orients the tail towards the target. Here, we report the crystal structure of TssK, a central component of the T6SS baseplate. We show that TssK is composed of three domains, and establish the contribution of each domain to the interaction with TssK partners. Importantly, this study reveals that the N-terminal domain of TssK is structurally homologous to the shoulder domain of phage receptor-binding proteins, and the C-terminal domain binds the membrane complex. We propose that TssK has conserved the domain of attachment to the virion particle but has evolved the reception domain to use the T6SS membrane complex as receptor.


    Organizational Affiliation

    Architecture et Fonction des Macromolécules Biologiques, Aix-Marseille Université, Campus de Luminy, Case 932, 13288 Marseille Cedex 09, France.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Type VI secretion protein
A, B, C
315Escherichia coliMutation(s): 0 
Gene Names: tssK
Find proteins for A0A0N8J9U9 (Escherichia coli)
Go to UniProtKB:  A0A0N8J9U9
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
llama nanobody raised against TssK, nbK18
D, E, F
125N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
llama nanobody raised against TssK, nbK27
N
125N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
PO4
Query on PO4

Download SDF File 
Download CCD File 
C
PHOSPHATE ION
O4 P
NBIIXXVUZAFLBC-UHFFFAOYSA-K
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.2 Å
  • R-Value Free: 0.220 
  • R-Value Work: 0.199 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 143.310α = 90.00
b = 150.280β = 90.00
c = 90.840γ = 90.00
Software Package:
Software NamePurpose
BUSTERrefinement
XDSdata reduction
XSCALEdata scaling
MOLREPphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
French National Research AgencyFranceANR-14-CE14-0006-02
French National Research AgencyFranceFRISBI

Revision History 

  • Version 1.0: 2017-06-28
    Type: Initial release
  • Version 1.1: 2017-07-05
    Type: Database references
  • Version 1.2: 2017-07-19
    Type: Source and taxonomy
  • Version 1.3: 2017-08-16
    Type: Data collection
  • Version 1.4: 2017-09-06
    Type: Author supporting evidence