3FU1

Crystal structure of the major pseudopilin from the type 2 secretion system of Vibrio cholerae


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.223 
  • R-Value Work: 0.178 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Calcium is essential for the major pseudopilin in the type 2 secretion system.

Korotkov, K.V.Gray, M.D.Kreger, A.Turley, S.Sandkvist, M.Hol, W.G.

(2009) J.Biol.Chem. 284: 25466-25470

  • DOI: 10.1074/jbc.C109.037655
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The pseudopilus is a key feature of the type 2 secretion system (T2SS) and is made up of multiple pseudopilins that are similar in fold to the type 4 pilins. However, pilins have disulfide bridges, whereas the major pseudopilins of T2SS do not. A key ...

    The pseudopilus is a key feature of the type 2 secretion system (T2SS) and is made up of multiple pseudopilins that are similar in fold to the type 4 pilins. However, pilins have disulfide bridges, whereas the major pseudopilins of T2SS do not. A key question is therefore how the pseudopilins, and in particular, the most abundant major pseudopilin, GspG, obtain sufficient stability to perform their function. Crystal structures of Vibrio cholerae, Vibrio vulnificus, and enterohemorrhagic Escherichia coli (EHEC) GspG were elucidated, and all show a calcium ion bound at the same site. Conservation of the calcium ligands fully supports the suggestion that calcium ion binding by the major pseudopilin is essential for the T2SS. Functional studies of GspG with mutated calcium ion-coordinating ligands were performed to investigate this hypothesis and show that in vivo protease secretion by the T2SS is severely impaired. Taking all evidence together, this allows the conclusion that, in complete contrast to the situation in the type 4 pili system homologs, in the T2SS, the major protein component of the central pseudopilus is dependent on calcium ions for activity.


    Organizational Affiliation

    Department of Biochemistry, Biomolecular Structure Center, University of Washington, Seattle, Washington 98195, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
General secretion pathway protein G
A, B
115Vibrio cholerae serotype O1 (strain ATCC 39315 / El Tor Inaba N16961)Mutation(s): 0 
Gene Names: epsG
Find proteins for P45773 (Vibrio cholerae serotype O1 (strain ATCC 39315 / El Tor Inaba N16961))
Go to UniProtKB:  P45773
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
ZN
Query on ZN

Download SDF File 
Download CCD File 
A, B
ZINC ION
Zn
PTFCDOFLOPIGGS-UHFFFAOYSA-N
 Ligand Interaction
CA
Query on CA

Download SDF File 
Download CCD File 
A, B
CALCIUM ION
Ca
BHPQYMZQTOCNFJ-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.9 Å
  • R-Value Free: 0.223 
  • R-Value Work: 0.178 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 50.638α = 90.00
b = 64.749β = 90.00
c = 65.041γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data scaling
PHASERphasing
Blu-Icedata collection
PDB_EXTRACTdata extraction
SCALEPACKdata scaling
HKL-2000data reduction
DENZOdata reduction
REFMACrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2009-07-28
    Type: Initial release
  • Version 1.1: 2011-07-13
    Type: Advisory, Version format compliance
  • Version 1.2: 2017-11-01
    Type: Refinement description