5I76

Crystal structure of FM318, a recombinant Fab adopted from cetuximab


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.92 Å
  • R-Value Free: 0.201 
  • R-Value Work: 0.166 
  • R-Value Observed: 0.168 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Bacterial production and structure-functional validation of a recombinant antigen-binding fragment (Fab) of an anti-cancer therapeutic antibody targeting epidermal growth factor receptor.

Kim, J.H.Sim, D.W.Park, D.Jung, T.G.Lee, S.Oh, T.Ha, J.R.Seok, S.H.Seo, M.D.Kang, H.C.Kim, Y.P.Won, H.S.

(2016) Appl Microbiol Biotechnol 100: 10521-10529

  • DOI: 10.1007/s00253-016-7717-z
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • Fragment engineering of monoclonal antibodies (mAbs) has emerged as an excellent paradigm to develop highly efficient therapeutic and/or diagnostic agents. Engineered mAb fragments can be economically produced in bacterial systems using recombinant D ...

    Fragment engineering of monoclonal antibodies (mAbs) has emerged as an excellent paradigm to develop highly efficient therapeutic and/or diagnostic agents. Engineered mAb fragments can be economically produced in bacterial systems using recombinant DNA technologies. In this work, we established recombinant production in Escherichia coli for monovalent antigen-binding fragment (Fab) adopted from a clinically used anticancer mAB drug cetuximab targeting epidermal growth factor receptor (EGFR). Recombinant DNA constructs were designed to express both polypeptide chains comprising Fab in a single vector and to secrete them to bacterial periplasmic space for efficient folding. Particularly, a C-terminal engineering to confer an interchain disulfide bond appeared to be able to enhance its heterodimeric integrity and EGFR-binding activity. Conformational relevance of the purified final product was validated by mass spectrometry and crystal structure at 1.9 Å resolution. Finally, our recombinant cetuximab-Fab was found to have strong binding affinity to EGFR overexpressed in human squamous carcinoma model (A431) cells. Its binding ability was comparable to that of cetuximab. Its EGFR-binding affinity was estimated at approximately 0.7 nM of Kd in vitro, which was quite stronger than the binding affinity of natural ligand EGF. Hence, the results validate that our construction could serve as an efficient platform to produce a recombinant cetuximab-Fab with a retained antigen-binding functionality.


    Organizational Affiliation

    Department of Biotechnology, Research Institute (RIBHS) and College of Biomedical and Health Science, Konkuk University, Chungju, Chungbuk, 27478, South Korea. wonhs@kku.ac.kr.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
FM318_light_chainA, C215Homo sapiens/Mus musculus xenograftMutation(s): 0 
Protein Feature View
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  • Reference Sequence

Find similar proteins by: Sequence  |  Structure

Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
FM318_heavy_cahinB, D224Homo sapiens/Mus musculus xenograftMutation(s): 0 
Protein Feature View
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  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 1.92 Å
  • R-Value Free: 0.201 
  • R-Value Work: 0.166 
  • R-Value Observed: 0.168 
  • Space Group: P 1 21 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 72.482α = 90
b = 68.037β = 101.85
c = 97.689γ = 90
Software Package:
Software NamePurpose
HKL-2000data processing
PHENIXrefinement

Structure Validation

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Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2016-12-07
    Type: Initial release
  • Version 1.1: 2017-08-30
    Changes: Data collection, Database references