7AKV

The cryo-EM structure of the Vag8-C1 inhibitor complex


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.60 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Molecular Basis for Bordetella pertussis Interference with Complement, Coagulation, Fibrinolytic, and Contact Activation Systems: the Cryo-EM Structure of the Vag8-C1 Inhibitor Complex.

Dhillon, A.Deme, J.C.Furlong, E.Roem, D.Jongerius, I.Johnson, S.Lea, S.M.

(2021) mBio 12

  • DOI: https://doi.org/10.1128/mBio.02823-20
  • Primary Citation of Related Structures:  
    7AKV

  • PubMed Abstract: 

    Complement, contact activation, coagulation, and fibrinolysis are serum protein cascades that need strict regulation to maintain human health. Serum glycoprotein, a C1 inhibitor (C1-INH), is a key regulator (inhibitor) of serine proteases of all the above-mentioned pathways. Recently, an autotransporter protein, virulence-associated gene 8 (Vag8), produced by the whooping cough pathogen, Bordetella pertussis , was shown to bind to C1-INH and interfere with its function. Here, we present the structure of the Vag8-C1-INH complex determined using cryo-electron microscopy at a 3.6-Å resolution. The structure shows a unique mechanism of C1-INH inhibition not employed by other pathogens, where Vag8 sequesters the reactive center loop of C1-INH, preventing its interaction with the target proteases. IMPORTANCE The structure of a 10-kDa protein complex is one of the smallest to be determined using cryo-electron microscopy at high resolution. The structure reveals that C1-INH is sequestered in an inactivated state by burial of the reactive center loop in Vag8. By so doing, the bacterium is able to simultaneously perturb the many pathways regulated by C1-INH. Virulence mechanisms such as the one described here assume more importance given the emerging evidence about dysregulation of contact activation, coagulation, and fibrinolysis leading to COVID-19 pneumonia.


  • Organizational Affiliation

    Sir William Dunn School of Pathology, Oxford, United Kingdom.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Plasma protease C1 inhibitor403Homo sapiensMutation(s): 0 
Gene Names: SERPING1C1INC1NH
UniProt & NIH Common Fund Data Resources
Find proteins for P05155 (Homo sapiens)
Explore P05155 
Go to UniProtKB:  P05155
PHAROS:  P05155
GTEx:  ENSG00000149131 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP05155
Sequence Annotations
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Vag8B [auth G]877Bordetella pertussisMutation(s): 0 
Gene Names: vag-8
UniProt
Find proteins for O66044 (Bordetella pertussis)
Explore O66044 
Go to UniProtKB:  O66044
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupO66044
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.60 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 
EM Software:
TaskSoftware PackageVersion
RECONSTRUCTIONRELION3.1
MODEL REFINEMENTPHENIXdev-3965

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Wellcome TrustUnited Kingdom100298
Wellcome TrustUnited Kingdom209194
Medical Research Council (MRC, United Kingdom)United KingdomMR/M011984/1
Wellcome TrustUnited Kingdom219477

Revision History  (Full details and data files)

  • Version 1.0: 2021-06-16
    Type: Initial release
  • Version 1.1: 2024-10-23
    Changes: Data collection, Database references, Structure summary