1D5I

UNLIGANDED GERMLINE PRECURSOR OF AN OXY-COPE CATALYTIC ANTIBODY


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.263 
  • R-Value Work: 0.216 

wwPDB Validation 3D Report Full Report


This is version 1.3 of the entry. See complete history

Literature

Conformational effects in biological catalysis: an antibody-catalyzed oxy-cope rearrangement.

Mundorff, E.C.Hanson, M.A.Varvak, A.Ulrich, H.Schultz, P.G.Stevens, R.C.

(2000) Biochemistry 39: 627-632

  • Primary Citation of Related Structures:  1D5B, 1D6V

  • PubMed Abstract: 
  • Antibody AZ-28 was generated against the chairlike transition-state analogue (TSA) 1 and catalyzes the oxy-Cope rearrangement of substrate 2 to product 3. The germline precursor to AZ-28 catalyzes the reaction with a 35-fold higher rate (k(cat)/k(unc ...

    Antibody AZ-28 was generated against the chairlike transition-state analogue (TSA) 1 and catalyzes the oxy-Cope rearrangement of substrate 2 to product 3. The germline precursor to AZ-28 catalyzes the reaction with a 35-fold higher rate (k(cat)/k(uncat) = 163 000), despite a 40-fold lower binding affinity for TSA.1 (K(D) = 670 nM). To determine the structural basis for the differences in the binding and catalytic properties of the germline and affinity-matured antibodies, the X-ray crystal structures of the unliganded and TSA.1 complex of antibody AZ-28 have been determined at 2.8 and 2.6 A resolution, respectively; the structures of the unliganded and TSA.1 complex of the germline precursor to AZ-28 were both determined at 2. 0 A resolution. In the affinity-matured antibody.hapten complex the TSA is fixed in a catalytically unfavorable conformation by a combination of van der Waals and hydrogen-bonding interactions. The 2- and 5-phenyl substituents of TSA.1 are almost perpendicular to the cyclohexyl ring, leading to decreased orbital overlap and decreased stabilization of the putative transition state. The active site of the germline antibody appears to have an increased degree of flexibility-CDRH3 moves 4.9 A outward from the active site upon binding of TSA.1. We suggest that this conformational flexibility in the germline antibody, which results in a lower binding affinity for TSA.1, allows dynamic changes in the dihedral angle of the 2-phenyl substituent along the reaction coordinate. These conformational changes in turn lead to enhanced orbital overlap and increased catalytic rate. These studies suggest that protein and substrate dynamics play a key role in this antibody-catalyzed reaction.


    Organizational Affiliation

    Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
CHIMERIC GERMLINE PRECURSOR OF OXY-COPE CATALYTIC ANTIBODY AZ-28 (LIGHT CHAIN)
L
211Homo sapiensGene Names: IGKC
Find proteins for P01834 (Homo sapiens)
Go to UniProtKB:  P01834
Entity ID: 2
MoleculeChainsSequence LengthOrganismDetails
CHIMERIC GERMLINE PRECURSOR OF OXY-COPE CATALYTIC ANTIBODY AZ-28 (HEAVY CHAIN)
H
221Homo sapiensGene Names: IGHG1
Find proteins for P01857 (Homo sapiens)
Go to UniProtKB:  P01857
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
CD
Query on CD

Download SDF File 
Download CCD File 
L
CADMIUM ION
Cd
WLZRMCYVCSSEQC-UHFFFAOYSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.263 
  • R-Value Work: 0.216 
  • Space Group: P 1 21 1
Unit Cell:
Length (Å)Angle (°)
a = 53.170α = 90.00
b = 64.130β = 99.53
c = 75.950γ = 90.00
Software Package:
Software NamePurpose
DENZOdata reduction
CNSrefinement
SCALEPACKdata scaling
AMoREphasing

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2000-02-09
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Version format compliance
  • Version 1.3: 2017-06-21
    Type: Advisory, Database references, Source and taxonomy, Structure summary