6MXS

Crystal structure of the dimeric bH1-Fab variant [HC-Y33W,HC-D98F,HC-G99M]


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.229 
  • R-Value Work: 0.191 
  • R-Value Observed: 0.193 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Binding symmetry and surface flexibility mediate antibody self-association.

Schrag, J.D.Picard, M.E.Gaudreault, F.Gagnon, L.P.Baardsnes, J.Manenda, M.S.Sheff, J.Deprez, C.Baptista, C.Hogues, H.Kelly, J.F.Purisima, E.O.Shi, R.Sulea, T.

(2019) MAbs 11: 1300-1318

  • DOI: 10.1080/19420862.2019.1632114
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • Solution stability is an important factor in the optimization of engineered biotherapeutic candidates such as monoclonal antibodies because of its possible effects on manufacturability, pharmacology, efficacy and safety. A detailed atomic understandi ...

    Solution stability is an important factor in the optimization of engineered biotherapeutic candidates such as monoclonal antibodies because of its possible effects on manufacturability, pharmacology, efficacy and safety. A detailed atomic understanding of the mechanisms governing self-association of natively folded protein monomers is required to devise predictive tools to guide screening and re-engineering along the drug development pipeline. We investigated pairs of affinity-matured full-size antibodies and observed drastically different propensities to aggregate from variants differing by a single amino-acid. Biophysical testing showed that antigen-binding fragments (Fabs) from the aggregating antibodies also reversibly associated with equilibrium dissociation constants in the low-micromolar range. Crystal structures (PDB accession codes 6MXR, 6MXS, 6MY4, 6MY5) and bottom-up hydrogen-exchange mass spectrometry revealed that Fab self-association occurs in a symmetric mode that involves the antigen complementarity-determining regions. Subtle local conformational changes incurred upon point mutation of monomeric variants foster formation of complementary polar interactions and hydrophobic contacts to generate a dimeric Fab interface. Testing of popular in silico tools generally indicated low reliabilities for predicting the aggregation propensities observed. A structure-aggregation data set is provided here in order to stimulate further improvements of in silico tools for prediction of native aggregation. Incorporation of intermolecular docking, conformational flexibility, and short-range packing interactions may all be necessary features of the ideal algorithm.


    Organizational Affiliation

    Human Health Therapeutics Research Centre, National Research Council Canada , Montreal , QC H4P 2R2 , Canada.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
anti-VEGF-A Fab fragment bH1 heavy chain
A, H
236Homo sapiensMutation(s): 0 
Gene Names: HEL-214
Find proteins for V9HW68 (Homo sapiens)
Go to UniProtKB:  V9HW68
Protein Feature View
  • Reference Sequence

Find similar proteins by: Sequence  |  Structure

Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
anti-VEGF-A Fab fragment bH1 light chain
B, L
218Homo sapiensMutation(s): 0 
Find proteins for Q7Z3Y4 (Homo sapiens)
Go to UniProtKB:  Q7Z3Y4
Protein Feature View
  • Reference Sequence
Small Molecules
Ligands 3 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
EDO
Query on EDO

Download CCD File 
B
1,2-ETHANEDIOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
 Ligand Interaction
CL
Query on CL

Download CCD File 
B, L
CHLORIDE ION
Cl
VEXZGXHMUGYJMC-UHFFFAOYSA-M
 Ligand Interaction
NA
Query on NA

Download CCD File 
L
SODIUM ION
Na
FKNQFGJONOIPTF-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.95 Å
  • R-Value Free: 0.229 
  • R-Value Work: 0.191 
  • R-Value Observed: 0.193 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 65.679α = 90
b = 95.96β = 103.68
c = 110.11γ = 90
Software Package:
Software NamePurpose
Aimlessdata scaling
REFMACrefinement
PDB_EXTRACTdata extraction
iMOSFLMdata reduction
MOLREPphasing

Structure Validation

View Full Validation Report



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2019-07-31
    Type: Initial release
  • Version 1.1: 2019-09-25
    Changes: Data collection, Database references