3UEP

Crystal structure of YscQ-C from Yersinia pseudotuberculosis


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.25 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.202 

wwPDB Validation 3D Report Full Report


This is version 1.0 of the entry. See complete history

Literature

Two Translation Products of Yersinia yscQ Assemble To Form a Complex Essential to Type III Secretion.

Bzymek, K.P.Hamaoka, B.Y.Ghosh, P.

(2012) Biochemistry 51: 1669-1677

  • DOI: 10.1021/bi201792p

  • PubMed Abstract: 
  • The bacterial flagellar C-ring is composed of two essential proteins, FliM and FliN. The smaller protein, FliN, is similar to the C-terminus of the larger protein, FliM, both being composed of SpoA domains. While bacterial type III secretion (T3S) sy ...

    The bacterial flagellar C-ring is composed of two essential proteins, FliM and FliN. The smaller protein, FliN, is similar to the C-terminus of the larger protein, FliM, both being composed of SpoA domains. While bacterial type III secretion (T3S) systems encode many proteins in common with the flagellum, they mostly have a single protein in place of FliM and FliN. This protein resembles FliM at its N-terminus and is as large as FliM but is more like FliN at its C-terminal SpoA domain. We have discovered that a FliN-sized cognate indeed exists in the Yersinia T3S system to accompany the FliM-sized cognate. The FliN-sized cognate, YscQ-C, is the product of an internal translation initiation site within the locus encoding the FliM-sized cognate YscQ. Both intact YscQ and YscQ-C were found to be required for T3S, indicating that the internal translation initiation site, which is conserved in some but not all YscQ orthologs, is crucial for function. The crystal structure of YscQ-C revealed a SpoA domain that forms a highly intertwined, domain-swapped homodimer, similar to those observed in FliN and the YscQ ortholog HrcQ(B). A single YscQ-C homodimer associated reversibly with a single molecule of intact YscQ, indicating conformational differences between the SpoA domains of intact YscQ and YscQ-C. A "snap-back" mechanism suggested by the structure can account for this. The 1:2 YscQ-YscQ-C complex is a close mimic of the 1:4 FliM-FliN complex and the likely building block of the putative Yersinia T3S system C-ring.


    Organizational Affiliation

    Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0375, United States.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
YscQ-C, type III secretion protein
A, B
96Yersinia pseudotuberculosis serotype I (strain IP32953)Mutation(s): 0 
Gene Names: yscQ
Find proteins for P40296 (Yersinia pseudotuberculosis serotype I (strain IP32953))
Go to UniProtKB:  P40296
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.25 Å
  • R-Value Free: 0.233 
  • R-Value Work: 0.202 
  • Space Group: H 3 2
Unit Cell:
Length (Å)Angle (°)
a = 114.130α = 90.00
b = 114.130β = 90.00
c = 88.560γ = 120.00
Software Package:
Software NamePurpose
MOLREPphasing
PHENIXrefinement
HKL-3000data collection
XSCALEdata scaling
XDSdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2012-04-04
    Type: Initial release