3CI0

The Crystal Structure of the GspK-GspI-GspJ complex from enterotoxigenic Escherichia coli Type 2 Secretion System

• PDB DOI: https://doi.org/10.2210/pdb3CI0/pdb

• Classification: PROTEIN TRANSPORT
• Organism(s): Escherichia coli
• Expression System: Escherichia coli BL21(DE3)
• Mutation(s): No 


• Deposited: 2008-03-10 Released: 2008-04-29 
• Deposition Author(s): Korotkov, K.V., Hol, W.G.J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.20 Å
• R-Value Free: 0.259 
• R-Value Work: 0.192 
• R-Value Observed: 0.195 

Literature

Structure of the GspK-GspI-GspJ complex from the enterotoxigenic Escherichia coli type 2 secretion system.

Korotkov, K.V., Hol, W.G.

(2008) Nat Struct Mol Biol 15: 462-468

• PubMed: 18438417 
• DOI: https://doi.org/10.1038/nsmb.1426
• Primary Citation of Related Structures:  
  3CI0


• PubMed Abstract: 
  

  Gram-negative bacteria translocate various proteins including virulence factors across their outer membrane via type 2 secretion systems (T2SSs). T2SSs are thought to contain a pseudopilus, a subcomplex formed by one major and several minor pseudopilins. We report the crystal structure of the complex formed by three minor pseudopilins from enterotoxigenic Escherichia coli. The GspK-GspI-GspJ complex has quasihelical characteristics and an architecture consistent with a localization at the pseudopilus tip. The alpha-domain of GspK has a previously unobserved fold with an unexpected dinuclear metal binding site. The area surrounding its disulfide bridge is conserved and might interact with other T2SS components or with secreted proteins.

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Organizational Affiliation: 

Department of Biochemistry, Biomolecular Structure Center, University of Washington, Box 357742, Seattle, Washington 98195, USA.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 3-mer - A1B1C1 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content

• Total Structure Weight: 62.64 kDa 
• Atom Count: 4,302 
• Modelled Residue Count: 517 
• Deposited Residue Count: 550 
• Unique protein chains: 3

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Pseudopilin GspI	A [auth I]	89	Escherichia coli	Mutation(s): 0  Gene Names: gspI
UniProt
Find proteins for Q8VPC3 (Escherichia coli) Explore Q8VPC3  Go to UniProtKB:  Q8VPC3

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
Pseudopilin GspJ	B [auth J]	163	Escherichia coli	Mutation(s): 0  Gene Names: gspJ
UniProt
Find proteins for A0A4C3GMC1 (Escherichia coli) Explore A0A4C3GMC1  Go to UniProtKB:  A0A4C3GMC1

Entity ID: 3
Molecule	Chains	Sequence Length	Organism	Details	Image
Pseudopilin GspK	C [auth K]	298	Escherichia coli	Mutation(s): 0  Gene Names: gspK
UniProt
Find proteins for Q8VLK7 (Escherichia coli) Explore Q8VLK7  Go to UniProtKB:  Q8VLK7

Small Molecules

Ligands 2 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
CA	E [auth I], F [auth K], G [auth K]	CALCIUM ION Ca BHPQYMZQTOCNFJ-UHFFFAOYSA-N
CL	D [auth I]	CHLORIDE ION Cl VEXZGXHMUGYJMC-UHFFFAOYSA-M

Modified Residues  1 Unique
ID	Chains	Type	Formula	2D Diagram	Parent
MSE	A [auth I]	L-PEPTIDE LINKING	C5 H11 N O2 Se		MET

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.20 Å
• R-Value Free: 0.259 
• R-Value Work: 0.192 
• R-Value Observed: 0.195 
• Space Group: P 4₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 96.118	α = 90
b = 96.118	β = 90
c = 108.436	γ = 90

Software Package:

Software Name	Purpose
MOSFLM	data reduction
SCALA	data scaling
SHARP	phasing
REFMAC	refinement
PDB_EXTRACT	data extraction

Structure Validation

Entry History 

Deposition Data

• Released Date: 2008-04-29 
Deposition Author(s): Korotkov, K.V., Hol, W.G.J.

Revision History  

• Version 1.0: 2008-04-29
  Type: Initial release
  
• Version 1.1: 2011-07-13
  Changes: Advisory, Version format compliance