6BZ4

Human IgG1 lacking complement-dependent cytotoxicity: hu3S193 Fc mutant K322A


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.249 
  • R-Value Work: 0.212 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Global conformational changes in IgG-Fc upon mutation of the FcRn-binding site are not associated with altered antibody-dependent effector functions.

Burvenich, I.J.G.Farrugia, W.Liu, Z.Makris, D.King, D.Gloria, B.Perani, A.Allan, L.C.Scott, A.M.Ramsland, P.A.

(2018) Biochem. J. 475: 2179-2190

  • DOI: 10.1042/BCJ20180139

  • PubMed Abstract: 
  • Antibody engineering is important for many diagnostic and clinical applications of monoclonal antibodies. We recently reported a series of fragment crystallizable (Fc) mutations targeting the neonatal Fc receptor (FcRn) site on a Lewis Y (Le <sup>y < ...

    Antibody engineering is important for many diagnostic and clinical applications of monoclonal antibodies. We recently reported a series of fragment crystallizable (Fc) mutations targeting the neonatal Fc receptor (FcRn) site on a Lewis Y (Le y ) binding IgG1, hu3S193. The hu3S193 variants displayed shortened in vivo half-lives and may have potential for radioimaging or radiotherapy of Le y -positive tumors. Here, we report Fc crystal structures of wild-type hu3S193, seven FcRn-binding site variants, and a variant lacking C1q binding or complement-dependent cytotoxicity (CDC) activity. The Fc conformation of the FcRn-binding sites was similar for wild-type and all mutants of hu3S193 Fc, which suggests that FcRn interactions were directly affected by the amino acid substitutions. The C1q-binding site mutant Fc was nearly identical with the wild-type Fc. Surprisingly, several hu3S193 Fc variants showed large changes in global structure compared with wild-type Fc. All hu3S193 Fc mutants had similar antibody-dependent cellular cytotoxicity, despite some with conformations expected to diminish Fc gamma receptor binding. Several hu3S193 variants displayed altered CDC, but there was no correlation with the different Fc conformations. All versions of hu3S193, except the C1q-binding site mutant, bound C1q, suggesting that the altered CDC of some variants could result from different propensities to form IgG hexamers after engaging Le y on target cells. Overall, our findings support the concept that the antibody Fc is both flexible and mobile in solution. Structure-based design approaches should take into account the conformational plasticity of the Fc when engineering antibodies with optimal effector properties.


    Organizational Affiliation

    Faculty of Medicine, University of Melbourne, Melbourne, VIC, Australia.,School of Cancer Medicine, La Trobe University, Melbourne, VIC, Australia.,Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, Melbourne, Australia.,Burnet Institute, Melbourne, VIC, Australia paul.ramsland@rmit.edu.au andrew.scott@onjcri.org.au.,Department of Immunology, Monash University, Melbourne, VIC, Australia.,School of Science, RMIT University, Bundoora, VIC, Australia.,Burnet Institute, Melbourne, VIC, Australia.,Tumour Targeting Laboratory, Olivia Newton-John Cancer Research Institute, Melbourne, Australia paul.ramsland@rmit.edu.au andrew.scott@onjcri.org.au.,Department of Surgery Austin Health, University of Melbourne, Heidelberg, VIC, Australia.,Department of Molecular Imaging and Therapy, Austin Health, University of Melbourne, Melbourne, Australia.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Immunoglobulin gamma-1 heavy chain
A, B
208Homo sapiensMutation(s): 1 
Find proteins for P0DOX5 (Homo sapiens)
Go to UniProtKB:  P0DOX5
Small Molecules
Ligands 5 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
MAN
Query on MAN

Download SDF File 
Download CCD File 
A, B
ALPHA-D-MANNOSE
C6 H12 O6
WQZGKKKJIJFFOK-PQMKYFCFSA-N
 Ligand Interaction
FUC
Query on FUC

Download SDF File 
Download CCD File 
A
ALPHA-L-FUCOSE
C6 H12 O5
SHZGCJCMOBCMKK-SXUWKVJYSA-N
 Ligand Interaction
EDO
Query on EDO

Download SDF File 
Download CCD File 
B
1,2-ETHANEDIOL
ETHYLENE GLYCOL
C2 H6 O2
LYCAIKOWRPUZTN-UHFFFAOYSA-N
 Ligand Interaction
BMA
Query on BMA

Download SDF File 
Download CCD File 
A, B
BETA-D-MANNOSE
C6 H12 O6
WQZGKKKJIJFFOK-RWOPYEJCSA-N
 Ligand Interaction
NAG
Query on NAG

Download SDF File 
Download CCD File 
A, B
N-ACETYL-D-GLUCOSAMINE
C8 H15 N O6
OVRNDRQMDRJTHS-FMDGEEDCSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.249 
  • R-Value Work: 0.212 
  • Space Group: P 21 21 21
Unit Cell:
Length (Å)Angle (°)
a = 49.324α = 90.00
b = 79.502β = 90.00
c = 138.221γ = 90.00
Software Package:
Software NamePurpose
XDSdata scaling
XDSdata reduction
PHENIXphasing
PHENIXrefinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Health and Medical Research Council (Australia)Australia542512
National Health and Medical Research Council (Australia)Australia1030469

Revision History 

  • Version 1.0: 2018-06-13
    Type: Initial release
  • Version 1.1: 2018-07-18
    Type: Data collection, Database references