9MPW | pdb_00009mpw

SARS-CoV2 Spike S2 Subunit in complex with M15 Antibody Fragment


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.37 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

Clonotype-enriched somatic hypermutations drive affinity maturation of a public human antibody targeting an occluded sarbecovirus epitope.

Rao, V.N.Sapse, I.A.Cohn, H.Yoo, D.K.Tong, P.Clark, J.J.Bozarth, B.Chen, Y.Srivastava, K.Singh, G.Krammer, F.Simon, V.Wesemann, D.R.Bajic, G.Coelho, C.H.

(2025) Cell Rep 44: 116122-116122

  • DOI: https://doi.org/10.1016/j.celrep.2025.116122
  • Primary Citation of Related Structures:  
    9MPW

  • PubMed Abstract: 

    Investigating public antibodies that recognize conserved epitopes is critical for vaccine development. Identifying somatic hypermutations (SHMs) that enhance antigen affinity in these public antibodies is key to guiding vaccine design for better protection against pathogens. We propose that affinity-enhancing SHMs are selectively enriched in public antibody clonotypes, surpassing the background frequency seen in antibodies carrying the same V genes but with different epitope specificities. Using M15, a human IGHV4-59/IGKV3-20 public antibody as a model, we compare SHM signatures in antibodies that use the same V genes but recognize other epitopes. We identified clonotype-enriched mutations in the light chain of M15 and showed that, in combination, these SHMs enhance binding to a previously uncharacterized Sarbecovirus epitope, with antibody responses to it increasing after sequential vaccination. Our findings identify convergence and clonotype enrichment as features of affinity-enhancing SHMs in public antibodies, which can help guide vaccine design aimed at eliciting such antibodies.


  • Organizational Affiliation
    • Department of Microbiology, Icahn School of Medicine at Mount Sinai, New York, NY, USA; Center for Vaccine Research and Pandemic Preparedness, Icahn School of Medicine at Mount Sinai, New York, NY, USA; Graduate School of Biomedical Sciences, Icahn School of Medicine at Mount Sinai, New York, NY, USA.

Macromolecules
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Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Spike protein S2A [auth S]624Severe acute respiratory syndrome coronavirus 2Mutation(s): 0 
Gene Names: S2
UniProt
Find proteins for P0DTC2 (Severe acute respiratory syndrome coronavirus 2)
Explore P0DTC2 
Go to UniProtKB:  P0DTC2
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP0DTC2
Glycosylation
Glycosylation Sites: 5Go to GlyGen: P0DTC2-1
Sequence Annotations
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  • Reference Sequence
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Entity ID: 2
MoleculeChains Sequence LengthOrganismDetailsImage
Fab M15 Heavy ChainB [auth H]217Homo sapiensMutation(s): 0 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
Glycosylation
Glycosylation Sites: 1
Sequence Annotations
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  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 3
MoleculeChains Sequence LengthOrganismDetailsImage
fAb M15 Light ChainC [auth L]215Homo sapiensMutation(s): 0 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
Sequence Annotations
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  • Reference Sequence
Oligosaccharides

Help

Entity ID: 4
MoleculeChains Length2D Diagram Glycosylation3D Interactions
2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranoseD [auth A]2N-Glycosylation
Glycosylation Resources
GlyTouCan:  G42666HT
GlyCosmos:  G42666HT
GlyGen:  G42666HT
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.37 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 
EM Software:
TaskSoftware PackageVersion
MODEL REFINEMENTPHENIX1.20.1_4487
RECONSTRUCTIONcryoSPARC

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)United StatesAI168178

Revision History  (Full details and data files)

  • Version 1.0: 2025-07-09
    Type: Initial release
  • Version 1.1: 2026-03-04
    Changes: Data collection, Database references