1UCB | pdb_00001ucb

STRUCTURE OF UNCOMPLEXED FAB COMPARED TO COMPLEX (1CLY, 1CLZ)

• PDB DOI: https://doi.org/10.2210/pdb1UCB/pdb

• Classification: IMMUNOGLOBULIN
• Organism(s): Homo sapiens
• Expression System: Mus musculus
• Mutation(s): No 


• Deposited: 1996-02-06 Released: 1997-03-12 
• Deposition Author(s): Sheriff, S., Bajorath, J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free: 
  0.276 (Depositor) 
• R-Value Work: 
  0.200 (Depositor), 0.183 (DCC) 
• R-Value Observed: 
  0.200 (Depositor) 

Starting Models: experimental

Literature

X-ray structure of the uncomplexed anti-tumor antibody BR96 and comparison with its antigen-bound form.

Sheriff, S., Chang, C.Y., Jeffrey, P.D., Bajorath, J.

(1996) J Mol Biology 259: 938-946

• PubMed: 8683596 
• DOI: https://doi.org/10.1006/jmbi.1996.0371
• Primary Citation Related Structures: 
  1UCB


• PubMed Abstract: 
  

  The X-ray structure of the uncomplexed human chimeric Fab' of the anti-tumor antibody BR96 has been determined at 2.6 A resolution. The structure has been compared with Lewis Y antigen-complexed structures of BR96 which were determined previously. The comparison reveals segmental motions and/or conformational rearrangements of three CDR loops (L1, L3, and H2), whereas CDR H3 does not undergo changes upon complexation despite its significant main-chain contacts to the carbohydrate antigen. In light of the uncomplexed chimeric Fab' structure reported here, the previously observed high mobility of the CL:CH1 domains of the complexed chimeric BR96 Fab is rationalized as a "swinging" motion approximately about the axis of the elbow bend.

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Organizational Affiliation: 
• Bristol-Myers Squibb Pharmaceutical Research Institute, Princeton, NJ 08543-4000, USA.

Biological Assembly 1  

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B1 

Biological assembly 1 assigned by authors and generated by PISA (software)

Macromolecule Content 

• Total Structure Weight: 47.78 kDa 
• Atom Count: 3,378 
• Modeled Residue Count: 435 
• Deposited Residue Count: 438 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
CHIMERIC HUMAN/MOUSE IGG FAB FRAGMENT BR96	A [auth L]	219	Homo sapiens	Mutation(s): 0
UniProt & NIH Common Fund Data Resources
Find proteins for P01834 (Homo sapiens) Explore P01834  Go to UniProtKB:  P01834
PHAROS:  P01834

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
CHIMERIC HUMAN/MOUSE IGG FAB FRAGMENT BR96	B [auth H]	219	Homo sapiens	Mutation(s): 0

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
SO4	C [auth L]	SULFATE ION O4 S QAOWNCQODCNURD-UHFFFAOYSA-L

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.50 Å
• R-Value Free:  0.276 (Depositor) 
• R-Value Work:  0.200 (Depositor), 0.183 (DCC) 
• R-Value Observed: 0.200 (Depositor) 

Space Group: P 2₁ 2₁ 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 61.1	α = 90
b = 174.3	β = 90
c = 45.6	γ = 90

Software Package:

Software Name	Purpose
XDS	data scaling
XSCALE	data scaling
BRUTE	model building
MERLOT	phasing
X-PLOR	refinement
XDS	data reduction
BRUTE	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 1997-03-12 
Deposition Author(s): Sheriff, S., Bajorath, J.

Revision History  

• Version 1.0: 1997-03-12
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2023-08-09
  Changes: Database references, Derived calculations, Refinement description
• Version 1.4: 2024-11-20
  Changes: Data collection, Structure summary