6A77

Crystal structure of the fifth immunoglobulin domain (Ig5) of human Robo1 in complex with the Fab fragment of murine monoclonal antibody B5209B


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.278 
  • R-Value Work: 0.238 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Affinity Improvement of a Cancer-Targeted Antibody through Alanine-Induced Adjustment of Antigen-Antibody Interface.

Yamashita, T.Mizohata, E.Nagatoishi, S.Watanabe, T.Nakakido, M.Iwanari, H.Mochizuki, Y.Nakayama, T.Kado, Y.Yokota, Y.Matsumura, H.Kawamura, T.Kodama, T.Hamakubo, T.Inoue, T.Fujitani, H.Tsumoto, K.

(2019) Structure 27: 519

  • DOI: 10.1016/j.str.2018.11.002
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • To investigate favorable single amino acid substitutions that improve antigen-antibody interactions, alanine (Ala) mutagenesis scanning of the interfacial residues of a cancer-targeted antibody, B5209B, was performed based on X-ray crystallography an ...

    To investigate favorable single amino acid substitutions that improve antigen-antibody interactions, alanine (Ala) mutagenesis scanning of the interfacial residues of a cancer-targeted antibody, B5209B, was performed based on X-ray crystallography analysis. Two substitutions were shown to significantly enhance the binding affinity for the antigen, by up to 30-fold. One substitution improved the affinity by a gain of binding enthalpy, whereas the other substitution improved the affinity by a gain of binding entropy. Molecular dynamics simulations showed that the enthalpic improvement could be attributed to the stabilization of distant salt bridges located at the periphery of the antigen-antibody interface. The entropic improvement was due to the release of water molecules that were stably trapped in the antigen-antibody interface of the wild-type antibody. Importantly, these effects of the Ala substitutions were caused by subtle adjustments of the binding interface. These results will be helpful to design high-affinity antibodies with avoiding entropy-enthalpy compensation.


    Organizational Affiliation

    Laboratory for Systems Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, 4-6-1, Komaba, Meguro-ku, Tokyo 153-8904, Japan.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Roundabout homolog 1
A
91Homo sapiensMutation(s): 0 
Gene Names: ROBO1 (DUTT1)
Find proteins for Q9Y6N7 (Homo sapiens)
Go to Gene View: ROBO1
Go to UniProtKB:  Q9Y6N7
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Light chain of the anti-human Robo1 antibody B5209B Fab
L
211N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Entity ID: 3
MoleculeChainsSequence LengthOrganismDetails
Heavy chain of the anti-human Robo1 antibody B5209B Fab
H
221N/AMutation(s): 0 
Protein Feature View is not available: No corresponding UniProt sequence found.
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.278 
  • R-Value Work: 0.238 
  • Space Group: P 43 21 2
Unit Cell:
Length (Å)Angle (°)
a = 100.566α = 90.00
b = 100.566β = 90.00
c = 122.756γ = 90.00
Software Package:
Software NamePurpose
HKL-2000data reduction
Cootmodel building
REFMACrefinement
PHASERphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
JapanFIRST Program-MDADD

Revision History 

  • Version 1.0: 2019-01-30
    Type: Initial release
  • Version 1.1: 2019-03-20
    Type: Data collection, Database references