6OEF

PolyAla Model of the O-layer from the Type 4 Secretion System of H. pylori

• PDB DOI: https://doi.org/10.2210/pdb6OEF/pdb
• EM Map EMD-20020: EMDB EMDataResource

• Classification: TRANSLOCASE
• Organism(s): Helicobacter pylori
• Mutation(s): No 


• Deposited: 2019-03-27 Released: 2019-07-03 
• Deposition Author(s): Chung, J.M., Sheedlo, M.J., Campbell, A., Sawhney, N., Frick-Cheng, A.E., Lacy, D.B., Cover, T.L., Ohi, M.D.
• Funding Organization(s): National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID), National Institutes of Health/National Cancer Institute (NIH/NCI), National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS), Other government

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 3.80 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Structure of the Helicobacter pylori Cag type IV secretion system.

Chung, J.M., Sheedlo, M.J., Campbell, A.M., Sawhney, N., Frick-Cheng, A.E., Lacy, D.B., Cover, T.L., Ohi, M.D.

(2019) Elife 8

• PubMed: 31210639 
• DOI: https://doi.org/10.7554/eLife.47644
• Primary Citation of Related Structures:  
  6ODI, 6ODJ, 6OEE, 6OEF, 6OEG, 6OEH


• PubMed Abstract: 
  

  Bacterial type IV secretion systems (T4SSs) are molecular machines that can mediate interbacterial DNA transfer through conjugation and delivery of effector molecules into host cells. The Helicobacter pylori Cag T4SS translocates CagA, a bacterial oncoprotein, into gastric cells, contributing to gastric cancer pathogenesis. We report the structure of a membrane-spanning Cag T4SS assembly, which we describe as three sub-assemblies: a 14-fold symmetric outer membrane core complex (OMCC), 17-fold symmetric periplasmic ring complex (PRC), and central stalk. Features that differ markedly from those of prototypical T4SSs include an expanded OMCC and unexpected symmetry mismatch between the OMCC and PRC. This structure is one of the largest bacterial secretion system assemblies ever reported and illustrates the remarkable structural diversity that exists among bacterial T4SSs.

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Organizational Affiliation: 

Life Sciences Institute, University of Michigan, Ann Arbor, United States.

Biological Assembly 1  

Global Symmetry: Cyclic - C14  (Explore in 3D)
Global Stoichiometry: Homo 14-mer - A14 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 872.41 kDa 
• Atom Count: 51,240 
• Modelled Residue Count: 10,248 
• Deposited Residue Count: 10,248 
• Unique protein chains: 1

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PolyAla Model of OMCC O-Layer	A, B, C, D, E, F, G, H, I, J, K, L, M, N	732	Helicobacter pylori	Mutation(s): 0

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 3.80 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Structure Validation

Entry History & Funding Information

Deposition Data

• Released Date: 2019-07-03 
Deposition Author(s): Chung, J.M., Sheedlo, M.J., Campbell, A., Sawhney, N., Frick-Cheng, A.E., Lacy, D.B., Cover, T.L., Ohi, M.D.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)	United States	NIH AI118932
National Institutes of Health/National Cancer Institute (NIH/NCI)	United States	CA116087
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)	United States	GM103310
Other government	United States	1I01BX004447

Revision History  

• Version 1.0: 2019-07-03
  Type: Initial release
  
• Version 1.1: 2019-12-04
  Changes: Author supporting evidence
• Version 1.2: 2020-03-25
  Changes: Structure summary
• Version 1.3: 2020-10-07
  Changes: Database references
• Version 1.4: 2024-03-13
  Changes: Database references