7KX4 | pdb_00007kx4

Anti-CCHFV ADI-36121 Fab

• PDB DOI: https://doi.org/10.2210/pdb7KX4/pdb

• Classification: IMMUNE SYSTEM
• Organism(s): Homo sapiens
• Expression System: Homo sapiens
• Mutation(s): No 


• Deposited: 2020-12-03 Released: 2021-12-01 
• Deposition Author(s): Mishra, A.K., McLellan, J.S.
• Funding Organization(s): National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.60 Å
• R-Value Free: 
  0.239 (Depositor), 0.238 (DCC) 
• R-Value Work: 
  0.198 (Depositor), 0.198 (DCC) 
• R-Value Observed: 
  0.200 (Depositor) 

Starting Models: experimental

Literature

Structural basis of synergistic neutralization of Crimean-Congo hemorrhagic fever virus by human antibodies.

Mishra, A.K., Hellert, J., Freitas, N., Guardado-Calvo, P., Haouz, A., Fels, J.M., Maurer, D.P., Abelson, D.M., Bornholdt, Z.A., Walker, L.M., Chandran, K., Cosset, F.L., McLellan, J.S., Rey, F.A.

(2022) Science 375: 104-109

• PubMed: 34793197 
• DOI: https://doi.org/10.1126/science.abl6502
• Primary Citation Related Structures: 
  7A59, 7A5A, 7KX4, 7L7R


• PubMed Abstract: 
  

  Crimean-Congo hemorrhagic fever virus (CCHFV) is the most widespread tick-borne zoonotic virus, with a 30% case fatality rate in humans. Structural information is lacking in regard to the CCHFV membrane fusion glycoprotein Gc—the main target of the host neutralizing antibody response—as well as antibody–mediated neutralization mechanisms. We describe the structure of prefusion Gc bound to the antigen-binding fragments (Fabs) of two neutralizing antibodies that display synergy when combined, as well as the structure of trimeric, postfusion Gc. The structures show the two Fabs acting in concert to block membrane fusion, with one targeting the fusion loops and the other blocking Gc trimer formation. The structures also revealed the neutralization mechanism of previously reported antibodies against CCHFV, providing the molecular underpinnings essential for developing CCHFV–specific medical countermeasures for epidemic preparedness.

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Organizational Affiliation: 
• Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX 78712, USA.
Institut Pasteur, Université de Paris, CNRS UMR 3569, Structural Virology Unit, 25-28 rue du Docteur Roux, Cedex 15, Paris, 75724 France.
CIRI-Centre International de Recherche en Infectiologie, Univ Lyon, Université Claude Bernard Lyon 1, Inserm, U1111, CNRS, UMR5308, ENS Lyon, 46 allée d'Italie, Lyon, 69007 France.
Institut Pasteur, Université de Paris, CNRS UMR 3528, Crystallography Platform C2RT, 25-28 rue du Docteur Roux, Cedex 15, Paris, 75724 France.
Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY 10461, USA.
Adimab LLC, Lebanon, NH 03766, USA.
Mapp Biopharmaceutical Inc., San Diego, CA 92121, USA.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

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

Biological Assembly 2  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

Biological assembly 2 assigned by authors and generated by PISA (software)

Macromolecule Content 

• Total Structure Weight: 96.16 kDa 
• Atom Count: 6,842 
• Modeled Residue Count: 856 
• Deposited Residue Count: 888 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
ADI-36121 Fab light chain	A, C	214	Homo sapiens	Mutation(s): 0

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
ADI-36121 Fab heavy chain	B, D	230	Homo sapiens	Mutation(s): 0

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.60 Å
• R-Value Free:  0.239 (Depositor), 0.238 (DCC) 
• R-Value Work:  0.198 (Depositor), 0.198 (DCC) 
• R-Value Observed: 0.200 (Depositor) 

Space Group: P 2₁ 2₁ 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 58.19	α = 90
b = 76.64	β = 90
c = 208.52	γ = 90

Software Package:

Software Name	Purpose
PHENIX	refinement
MOSFLM	data reduction
Aimless	data scaling
PHASER	phasing
PDB_EXTRACT	data extraction

Structure Validation

Entry History 

& Funding Information

Deposition Data

• Released Date: 2021-12-01 
Deposition Author(s): Mishra, A.K., McLellan, J.S.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)	United States	U19 AI142777

Revision History  

• Version 1.0: 2021-12-01
  Type: Initial release
  
• Version 1.1: 2022-01-19
  Changes: Database references
• Version 1.2: 2023-10-18
  Changes: Data collection, Refinement description
• Version 1.3: 2024-10-23
  Changes: Structure summary