6KDI

Antibody 64M-5 Fab including isoAsp in complex with dT(6-4)T


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.70 Å
  • R-Value Free: 0.259 
  • R-Value Work: 0.210 

wwPDB Validation 3D Report Full Report



Literature

Structural and biochemical basis of the formation of isoaspartate in the complementarity-determining region of antibody 64M-5 Fab.

Yokoyama, H.Mizutani, R.Noguchi, S.Hayashida, N.

(2019) Sci Rep 9: 18494-18494

  • DOI: 10.1038/s41598-019-54918-0
  • Structures With Same Primary Citation

  • PubMed Abstract: 
  • The formation of the isoaspartate (isoAsp) is one of spontaneous degradation processes of proteins, affecting their stability and activity. Here, we report for the first time the crystal structures of an antibody Fab that contains isoAsp in the compl ...

    The formation of the isoaspartate (isoAsp) is one of spontaneous degradation processes of proteins, affecting their stability and activity. Here, we report for the first time the crystal structures of an antibody Fab that contains isoAsp in the complementarity-determining region (CDR), along with biochemical studies to detect isoAsp. By comparing the elution profiles of cation-exchange chromatography, it was clarified that the antibody 64M-5 Fab is converted from the normal form to isoAsp form spontaneously and time-dependently under physiological conditions. The isoAsp residue was identified with tryptic peptide mapping, N-terminal sequencing, and the protein isoaspartyl methyltransferase assay. Based on the fluorescence quenching method, the isoAsp form of 64M-5 Fab shows a one order of magnitude lower binding constant for its dinucleotide ligand dT(6-4)T than the normal form. According to the structure of the isoAsp form, the conformation of CDR L1 is changed from the normal form to isoAsp form; the loss of hydrogen bonds involving the Asn28L side-chain, and structural conversion of the β-turn from type I to type II'. The formation of isoAsp leads to a large displacement of the side chain of His27dL, and decreased electrostatic interactions with the phosphate group of dT(6-4)T. Such structural changes should be responsible for the lower affinity of the isoAsp form for dT(6-4)T than the normal form. These findings may provide insight into neurodegenerative diseases (NDDs) and related diseases caused by misfolded proteins.


    Related Citations: 
    • Structures of the antibody 64M-5 Fab and its complex with dT(6-4)T indicate induced-fit and high-affinity mechanisms.
      Yokoyama, H., Mizutani, R., Noguchi, S., Hayashida, N.
      (2019) Acta Crystallogr F Struct Biol Commun 75: 80

    Organizational Affiliation

    Division of Molecular Gerontology and Anti-Ageing Medicine, Department of Biochemistry and Molecular Biology, Yamaguchi University Graduate School of Medicine, 1-1-1 Minami-Kogushi, Ube, Yamaguchi, 755-8505, Japan. hayasida@yamaguchi-u.ac.jp.



Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Anti-(6-4) photoproduct antibody 64M-5 Fab (light chain)L218Mus musculusMutation(s): 0 
Protein Feature View
 ( Mouse scroll to zoom / Hold left click to move )
  • Reference Sequence

Find similar proteins by: Sequence  |  Structure

Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
Anti-(6-4) photoproduct antibody 64M-5 Fab (heavy chain)H221Mus musculusMutation(s): 0 
Protein Feature View
 ( Mouse scroll to zoom / Hold left click to move )
  • Reference Sequence
  • Find similar nucleic acids by: Sequence   |   Structure
Entity ID: 3
MoleculeChainsLengthOrganism
DNA (5'-D(*(64T)P*(5PY))-3')A2synthetic construct
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.70 Å
  • R-Value Free: 0.259 
  • R-Value Work: 0.210 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 84.005α = 90
b = 102.903β = 90
c = 53.398γ = 90
Software Package:
Software NamePurpose
CNSrefinement
PDB_EXTRACTdata extraction
DENZOdata reduction
SCALEPACKdata scaling
X-PLORphasing

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
Japan Society for the Promotion of ScienceJapan17K07316

Revision History 

  • Version 1.0: 2019-12-18
    Type: Initial release