6SIH

Structure of bacterial flagellar capping protein FliD

• PDB DOI:  https://doi.org/10.2210/pdb6SIH/pdb
• EM Map EMD-10210: EMDB EMDataResource

• Classification: TRANSPORT PROTEIN
• Organism(s): Campylobacter jejuni
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2019-08-09 Released: 2020-05-27 
• Deposition Author(s): Al-Otaibi, N.S., Farrell, D., DiMaio, F., Bergeron, J.R.C.
• Funding Organization(s): Biotechnology and Biological Sciences Research Council

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 4.70 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

The cryo-EM structure of the bacterial flagellum cap complex suggests a molecular mechanism for filament elongation.

Al-Otaibi, N.S., Taylor, A.J., Farrell, D.P., Tzokov, S.B., DiMaio, F., Kelly, D.J., Bergeron, J.R.C.

(2020) Nat Commun 11: 3210-3210

• PubMed: 32587243 
• DOI: https://doi.org/10.1038/s41467-020-16981-4
• Primary Citation of Related Structures:  
  6SIH


• PubMed Abstract: 
  

The bacterial flagellum is a remarkable molecular motor, whose primary function in bacteria is to facilitate motility through the rotation of a filament protruding from the bacterial cell. A cap complex, consisting of an oligomer of the protein FliD, is localized at the tip of the flagellum, and is essential for filament assembly, as well as adherence to surfaces in some bacteria. However, the structure of the intact cap complex, and the molecular basis for its interaction with the filament, remains elusive. Here we report the cryo-EM structure of the Campylobacter jejuni cap complex, which reveals that FliD is pentameric, with the N-terminal region of the protomer forming an extensive set of contacts across several subunits, that contribute to FliD oligomerization. We also demonstrate that the native C. jejuni flagellum filament is 11-stranded, contrary to a previously published cryo-EM structure, and propose a molecular model for the filament-cap interaction.

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Organizational Affiliation: 

Randall Division of Cell and Molecular Biophysics, King's College London, London, UK. [e-mail].

Biological Assembly 1  

Global Symmetry: Dihedral - D5  (3D View)
Global Stoichiometry: Homo 10-mer - A10 

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

Macromolecule Content

• Total Structure Weight: 721.59 kDa 
• Atom Count: 37,310 
• Modelled Residue Count: 4,880 
• Deposited Residue Count: 6,630 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Flagellar hook-associated protein 2	A, B [auth H], C [auth B], D [auth F], E [auth C], F [auth G], G [auth D], H [auth I], I [auth E], J	663	Campylobacter jejuni	Mutation(s): 0  Gene Names: fliD, EC071_02365, B9U92_06665, CT954_02345, GXS76_000046
UniProt
Find proteins for A0A3I4YJR7 (Campylobacter jejuni) Explore A0A3I4YJR7  Go to UniProtKB:  A0A3I4YJR7

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 4.70 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2020-05-27 
Deposition Author(s): Al-Otaibi, N.S., Farrell, D., DiMaio, F., Bergeron, J.R.C.

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Funding Organization	Location	Grant Number
Biotechnology and Biological Sciences Research Council	United Kingdom	--

Revision History  

• Version 1.0: 2020-05-27
  Type: Initial release
  
• Version 1.1: 2020-06-03
  Changes: Database references
• Version 1.2: 2020-07-08
  Changes: Database references