Biological Assembly 1  

 3D View: Structure

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 9.02 kDa 
• Atom Count: 599 
• Modelled Residue Count: 70 
• Deposited Residue Count: 83 
• Unique protein chains: 1

1PGX

THE 1.66 ANGSTROMS X-RAY STRUCTURE OF THE B2 IMMUNOGLOBULIN-BINDING DOMAIN OF STREPTOCOCCAL PROTEIN G AND COMPARISON TO THE NMR STRUCTURE OF THE B1 DOMAIN

• DOI: 10.2210/pdb1PGX/pdb

• Classification: IMMUNOGLOBULIN BINDING PROTEIN
• Organism(s): Streptococcus
• Mutation(s): No 


• Deposited: 1992-04-03 Released: 1992-07-15 
• Deposition Author(s): Whitlow, M., Achari, A., Howard, A.J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.66 Å
• R-Value Observed: 0.191 

Literature

1.67-A X-ray structure of the B2 immunoglobulin-binding domain of streptococcal protein G and comparison to the NMR structure of the B1 domain.

Achari, A., Hale, S.P., Howard, A.J., Clore, G.M., Gronenborn, A.M., Hardman, K.D., Whitlow, M.

(1992) Biochemistry 31: 10449-10457

• PubMed: 1420164 
• DOI: 10.1021/bi00158a006
• Primary Citation of Related Structures:  
  1PGX


• PubMed Abstract: 
  

The structure of the B2 immunoglobulin-binding domain of streptococcal protein G has been determined at 1.67-A resolution using a combination of single isomorphous replacement (SIR) phasing and manual fitting of the coordinates of the NMR structure of B1 domain of streptococcal protein G [Gronenborn, A. M., et al. (1991) Science 253, 657-661]. The final R value was 0.191 for data between 8.0 and 1.67 A. The structure described here has 13 residues preceding the 57-residue Ig-binding domain and 13 additional residues following it, for a total of 83 residues. The 57-residue binding domain is well-determined in the structure, having an average B factor of 18.0. Only residues 8-77 could be located in the electron density maps, with the ends of the structure fading into disorder. Like the B1 domain, the B2 domain consists of four beta-strands and a single helix lying diagonally across the beta-sheet, with a -1, +3 chi, -1 topology. This small structure is extensively hydrogen-bonded and has a relatively large hydrophobic core. These structural observations may account for the exceptional stability of protein G. A comparison of the B2 domain X-ray structure and the B1 domain NMR structure showed minor differences in the turn between strands and two and a slight displacement of the helix relative to the sheet. Hydrogen bonds between crystallographically related molecules account for most of these differences.

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Related Citations: 

• A Novel, Highly Stable Fold of the Immunoglobulin Binding Domain of Streptococcal Protein G
  Gronenborn, A.M., Filpula, D.R., Essig, N.Z., Achari, A., Whitlow, M., Wingfield, P.T., Clore, G.M.
  (1991) Science 253: 657

• Structure and Evolution of the Streptococcal Genes Encoding Protein G
  Fahnestock, S.R., Alexander, P., Filpula, D., Nagle, J.
  (1990) Bacterial Immunoglobulin-binding Proteins 1: 133

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Organizational Affiliation: 

Protein Engineering Department, Enzon, Incorporated, Gaithersburg, Maryland 20877.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
PROTEIN G	A	83	Streptococcus	Mutation(s): 0
Find proteins for P06654 (Streptococcus sp. group G) Explore P06654  Go to UniProtKB:  P06654

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.66 Å
• R-Value Observed: 0.191 
• Space Group: P 1 2₁ 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 26.04	α = 90
b = 34.5	β = 100.84
c = 35.95	γ = 90

Software Package:

Software Name	Purpose
PROFFT	refinement

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1992-04-03 
• Released Date: 1992-07-15 
Deposition Author(s): Whitlow, M., Achari, A., Howard, A.J.

Revision History  

• Version 1.0: 1992-07-15
  Type: Initial release
  
• Version 1.1: 2008-03-24
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance