Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report | Ligand Interaction

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 25.23 kDa 
• Atom Count: 1685 
• Modelled Residue Count: 192 
• Deposited Residue Count: 223 
• Unique protein chains: 1

1Q0P

A domain of Factor B

• PDB DOI: 10.2210/pdb1Q0P/pdb

• Classification: HYDROLASE
• Organism(s): Homo sapiens
• Expression System: Escherichia coli
• Mutation(s): Yes 


• Deposited: 2003-07-17 Released: 2004-03-30 
• Deposition Author(s): Bhattacharya, A.A., Liddington, R.C.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free: 0.259 
• R-Value Work: 0.210 
• R-Value Observed: 0.210 

Literature

Crystal Structure of the A Domain from Complement Factor B Reveals an Integrin-like Open Conformation.

Bhattacharya, A.A., Lupher Jr., M.L., Staunton, D.E., Liddington, R.C.

(2004) Structure 12: 371-378

• PubMed: 15016353 
• DOI: 10.1016/j.str.2004.02.012
• Primary Citation of Related Structures:  
  1Q0P


• PubMed Abstract: 
  

Complement factor B is a 90 kDa protein consisting of three domains: a three-module complement control protein, a von Willebrand factor A domain, and a C-terminal serine protease (SP) domain that adopts a default inactive (zymogen) conformation. The interaction between factor B and pathogen-bound C3b is mediated by its A domain, triggering a conformational change in factor B that ultimately creates the "C3 convertase" of the alternative complement pathway. We report the crystal structure of the A domain from factor B and show that it contains an integrin-like MIDAS motif that adopts the "open" conformation typical of integrin-ligand complexes, with an acidic residue (provided by a fortuitous crystal contact) completing the coordination of the metal ion. Modeling studies indicate that the factor B A domain can also adopt the closed conformation, supporting the hypothesis that an "integrin-like switch" is conserved in complement proteins and perhaps in 60 other A domains found within the human proteome.

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Organizational Affiliation: 

The Burnham Institute, 10901 North Torrey Pines Road, La Jolla, CA 92037 USA.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Complement factor B	A	223	Homo sapiens	Mutation(s): 1  Gene Names: BF, CFB, BFD EC: 3.4.21.47
UniProt & NIH Common Fund Data Resources
Find proteins for P00751 (Homo sapiens) Explore P00751  Go to UniProtKB:  P00751
PHAROS:  P00751

Small Molecules

Ligands 1 Unique
ID	Chains	Name / Formula / InChI Key	2D Diagram
MN	B [auth A]	MANGANESE (II) ION Mn WAEMQWOKJMHJLA-UHFFFAOYSA-N

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.80 Å
• R-Value Free: 0.259 
• R-Value Work: 0.210 
• R-Value Observed: 0.210 
• Space Group: P 6₃

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 72.56	α = 90
b = 72.56	β = 90
c = 76.06	γ = 120

Software Package:

Software Name	Purpose
MOSFLM	data reduction
SCALA	data scaling
CNS	refinement
CCP4	data scaling
CNS	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2003-07-17 
• Released Date: 2004-03-30 
Deposition Author(s): Bhattacharya, A.A., Liddington, R.C.

Revision History  

• Version 1.0: 2004-03-30
  Type: Initial release
  
• Version 1.1: 2008-04-29
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance
• Version 1.3: 2018-04-04
  Changes: Data collection
• Version 1.4: 2021-10-27
  Changes: Database references, Derived calculations