1MCO

THREE-DIMENSIONAL STRUCTURE OF A HUMAN IMMUNOGLOBULIN WITH A HINGE DELETION

• PDB DOI: https://doi.org/10.2210/pdb1MCO/pdb

• Classification: IMMUNOGLOBULIN
• Organism(s): Homo sapiens
• Mutation(s): No 


• Deposited: 1993-02-25 Released: 1994-01-31 
• Deposition Author(s): Guddat, L.W., Edmundson, A.B.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 3.20 Å
• R-Value Work: 0.232 
• R-Value Observed: 0.232 

Literature

Three-dimensional structure of a human immunoglobulin with a hinge deletion.

Guddat, L.W., Herron, J.N., Edmundson, A.B.

(1993) Proc Natl Acad Sci U S A 90: 4271-4275

• PubMed: 8483943 
• DOI: https://doi.org/10.1073/pnas.90.9.4271
• Primary Citation of Related Structures:  
  1MCO


• PubMed Abstract: 
  

  X-ray analysis at 3.2-A resolution revealed that the Mcg IgG1 (lambda chain) immunoglobulin is a compact T-shaped molecule. Because of the hinge deletion, the Fc fragment lobe is pulled tightly upward into the junction of the Fab arms. Along the molecular twofold axis, the Fab arms are joined by an interchain disulfide bond between the two light chains. The antigen combining sites consist of large irregular cavities at the tips of the Fab regions. Potential complement (C1q) binding sites on Fc are sterically shielded by the Fab arms, but putative attachment sites are accessible for docking with the FcRI receptor on human monocytes and with protein A of Staphylococcus aureus.

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Organizational Affiliation: 

Harrington Cancer Center, Amarillo, TX 79106.

Biological Assembly 1  

Global Symmetry: Cyclic - C2  (Explore in 3D)
Global Stoichiometry: Hetero 4-mer - A2B2 

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

Macromolecule Content

• Total Structure Weight: 71.65 kDa 
• Atom Count: 5,041 
• Modelled Residue Count: 644 
• Deposited Residue Count: 644 
• Unique protein chains: 2

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
IGG1 MCG INTACT ANTIBODY (LIGHT CHAIN)	A [auth L]	216	Homo sapiens	Mutation(s): 0

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details	Image
IGG1 MCG INTACT ANTIBODY (HEAVY CHAIN)	B [auth H]	428	Homo sapiens	Mutation(s): 0
Glycosylation
Glycosylation Sites: 1

Oligosaccharides

Help

Entity ID: 3
Molecule	Chains	Length	2D Diagram	Glycosylation	3D Interactions
N-acetyl-alpha-neuraminic acid-(2-3)-beta-D-galactopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-2)-alpha-D-mannopyranose-(1-6)-[2-acetamido-2-deoxy-beta-D-glucopyranose-(1-2)-alpha-L-gulopyranose-(1-3)]beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-[beta-L-fucopyranose-(1-6)]2-acetamido-2-deoxy-beta-D-glucopyranose	C [auth A]	10		N-Glycosylation
Glycosylation Resources
GlyTouCan:  G18746ZC GlyCosmos:  G18746ZC

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 3.20 Å
• R-Value Work: 0.232 
• R-Value Observed: 0.232 
• Space Group: C 2 2 2₁

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 88.4	α = 90
b = 110	β = 90
c = 186.7	γ = 90

Software Package:

Software Name	Purpose
X-PLOR	model building
X-PLOR	refinement
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Released Date: 1994-01-31 
Deposition Author(s): Guddat, L.W., Edmundson, A.B.

Revision History  

• Version 1.0: 1994-01-31
  Type: Initial release
  
• Version 1.1: 2008-03-03
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Derived calculations, Version format compliance
• Version 1.3: 2017-11-29
  Changes: Derived calculations, Other
• Version 2.0: 2020-07-29
  Type: Remediation
  Reason: Carbohydrate remediation
  Changes: Atomic model, Data collection, Database references, Derived calculations, Structure summary
• Version 2.1: 2024-12-25
  Changes: Advisory, Data collection, Database references, Derived calculations, Structure summary