Biological Assembly 1  

 3D View: Structure | Electron Density

Global Symmetry: Cyclic - C2  (3D View)
Global Stoichiometry: Homo 2-mer - A2 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 48.88 kDa 
• Atom Count: 3499 
• Residue Count: 456 
• Unique protein chains: 1

1DSU

HUMAN FACTOR D, COMPLEMENT ACTIVATING ENZYME

• DOI: 10.2210/pdb1DSU/pdb

• Classification: HYDROLASE (SERINE PROTEASE)
• Organism(s): Homo sapiens
• Mutation(s): No 


• Deposited: 1995-09-15 Released: 1996-08-17 
• Deposition Author(s): Narayana, S.V.L., Volanakis, J.E., Delucas, L.J.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.203 
• R-Value Work: 0.188 
• R-Value Observed: 0.188 

Literature

Structure of human factor D. A complement system protein at 2.0 A resolution.

Narayana, S.V., Carson, M., el-Kabbani, O., Kilpatrick, J.M., Moore, D., Chen, X., Bugg, C.E., Volanakis, J.E., DeLucas, L.J.

(1994) J Mol Biol 235: 695-708

• PubMed: 8289289 
• DOI: 10.1006/jmbi.1994.1021
• Primary Citation of Related Structures:  
  1DSU


• PubMed Abstract: 
  

Factor D, an essential enzyme for the activation of the alternative pathway of the complement system, belongs to the serine protease superfamily. The crystal structure of the enzyme was solved by a combination of multiple isomorphous replacement and molecular replacement methods. The present model was refined to an R-factor of 18.8% using 23,681 observed reflections between 7.5 and 2.0 A resolution, with a root-mean-square deviation from standard bond lengths of 0.016 A. The two non-crystallographically related molecules in the triclinic unit cell have distinctive active site conformations. The protein has the general structural fold of a serine protease, but there are several unique amino acid substitutions resulting in significant alterations in the critical loops responsible for catalysis and substrate specificity in serine proteases. Factor D is the first complement serine protease whose three-dimensional structure has been determined.

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Related Citations: 

• Crystallization and Preliminary X-Ray Investigation of Factor D of Human Complement
  Narayana, S.V., Kilpatrick, J.M., El-Kabbani, O., Babu, Y.S., Bugg, C.E., Volanakis, J.E., Delucas, L.J.
  (1991) J Mol Biol 219: 1

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Organizational Affiliation: 

Center for Macromolecular Crystallography, University of Alabama at Birmingham 35294.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
FACTOR D	A, B	228	Homo sapiens	Mutation(s): 0  Gene Names: CFD, DF, PFD EC: 3.4.21.46
Find proteins for P00746 (Homo sapiens) Explore P00746  Go to UniProtKB:  P00746
NIH Common Fund Data Resources
PHAROS:  P00746 GTEx:  ENSG00000197766

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.00 Å
• R-Value Free: 0.203 
• R-Value Work: 0.188 
• R-Value Observed: 0.188 
• Space Group: P 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 40.99	α = 101.26
b = 65.02	β = 109.89
c = 40.36	γ = 74.32

Software Package:

Software Name	Purpose
XENGEN	data collection
X-PLOR	model building
X-PLOR	refinement
XENGEN	data reduction
X-PLOR	phasing

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 1995-09-15 
• Released Date: 1996-08-17 
Deposition Author(s): Narayana, S.V.L., Volanakis, J.E., Delucas, L.J.

Revision History 

• Version 1.0: 1996-08-17
  Type: Initial release
  
• Version 1.1: 2008-03-25
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance