6S3L

Structure of the core of the flagellar export apparatus from Vibrio mimicus, the FliPQR-FlhB complex.


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.20 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation   3D Report Full Report


This is version 1.0 of the entry. See complete history


Literature

The substrate specificity switch FlhB assembles onto the export gate to regulate type three secretion.

Kuhlen, L.Johnson, S.Zeitler, A.Baurle, S.Deme, J.C.Caesar, J.J.E.Debo, R.Fisher, J.Wagner, S.Lea, S.M.

(2020) Nat Commun 11: 1296-1296

  • DOI: 10.1038/s41467-020-15071-9
  • Primary Citation of Related Structures:  
    6S3L, 6S3R, 6S3S

  • PubMed Abstract: 
  • Protein secretion through type-three secretion systems (T3SS) is critical for motility and virulence of many bacteria. Proteins are transported through an export gate containing three proteins (FliPQR in flagella, SctRST in virulence systems). A fourth essential T3SS protein (FlhB/SctU) functions to "switch" secretion substrate specificity once the growing hook/needle reach their determined length ...

    Protein secretion through type-three secretion systems (T3SS) is critical for motility and virulence of many bacteria. Proteins are transported through an export gate containing three proteins (FliPQR in flagella, SctRST in virulence systems). A fourth essential T3SS protein (FlhB/SctU) functions to "switch" secretion substrate specificity once the growing hook/needle reach their determined length. Here, we present the cryo-electron microscopy structure of an export gate containing the switch protein from a Vibrio flagellar system at 3.2 Å resolution. The structure reveals that FlhB/SctU extends the helical export gate with its four predicted transmembrane helices wrapped around FliPQR/SctRST. The unusual topology of the FlhB/SctU helices creates a loop wrapped around the bottom of the closed export gate. Structure-informed mutagenesis suggests that this loop is critical in gating secretion and we propose that a series of conformational changes in the T3SS trigger opening of the gate through interactions between FlhB/SctU and FliPQR/SctRST.


    Organizational Affiliation

    Central Oxford Structural Microscopy and Imaging Centre, University of Oxford, Oxford, OX1 3RE, UK. susan.lea@path.ox.ac.uk.



Macromolecules
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Entity ID: 1
MoleculeChainsSequence LengthOrganismDetailsImage
Flagellar biosynthetic protein FliPA, B, C, D, E299Vibrio mimicus CAIM 602Mutation(s): 0 
Gene Names: fliPAL544_009685
Membrane Entity: Yes 
UniProt
Find proteins for A0A2J9UXT5 (Vibrio mimicus)
Explore A0A2J9UXT5 
Go to UniProtKB:  A0A2J9UXT5
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupA0A2J9UXT5
Protein Feature View
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  • Reference Sequence
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Entity ID: 2
MoleculeChainsSequence LengthOrganismDetailsImage
Flagellar biosynthetic protein FliRF260Vibrio mimicus CAIM 602Mutation(s): 0 
Gene Names: AL544_009675
Membrane Entity: Yes 
UniProt
Find proteins for A0A1D8S9I5 (Vibrio mimicus)
Explore A0A1D8S9I5 
Go to UniProtKB:  A0A1D8S9I5
Entity Groups  
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UniProt GroupA0A1D8S9I5
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Entity ID: 3
MoleculeChainsSequence LengthOrganismDetailsImage
Flagellar biosynthetic protein FliQG, H, I, J89Vibrio mimicus CAIM 602Mutation(s): 0 
Gene Names: fliQAL544_009680
Membrane Entity: Yes 
UniProt
Find proteins for A0A1D8S9F5 (Vibrio mimicus)
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Go to UniProtKB:  A0A1D8S9F5
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UniProt GroupA0A1D8S9F5
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Entity ID: 4
MoleculeChainsSequence LengthOrganismDetailsImage
Flagellar biosynthetic protein FlhBK415Vibrio mimicus CAIM 602Mutation(s): 0 
Gene Names: flhBAL544_009670
Membrane Entity: Yes 
UniProt
Find proteins for A0A1D8S9F8 (Vibrio mimicus)
Explore A0A1D8S9F8 
Go to UniProtKB:  A0A1D8S9F8
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UniProt GroupA0A1D8S9F8
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.20 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

Structure Validation

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Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Wellcome TrustUnited Kingdom100298
Wellcome TrustUnited Kingdom109136
Wellcome TrustUnited Kingdom201536
Medical Research Council (United Kingdom)United KingdomM011984
Wolfson FoundationUnited KingdomWL160052

Revision History  (Full details and data files)

  • Version 1.0: 2020-03-25
    Type: Initial release