Biological Assembly 1  

 3D View: Structure | Electron Density

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

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 37.20 kDa 
• Atom Count: 2576 
• Residue Count: 314 
• Unique protein chains: 1

1MD8

Monomeric structure of the active catalytic domain of complement protease C1r

• DOI: 10.2210/pdb1MD8/pdb

• Classification: HYDROLASE
• Organism(s): Homo sapiens
• Expression System: Trichoplusia ni
• Mutation(s): No 


• Deposited: 2002-08-07 Released: 2003-08-07 
• Deposition Author(s): Budayova-Spano, M., Grabarse, W., Thielens, N.M., Hillen, H., Lacroix, M., Schmidt, M., Fontecilla-Camps, J., Arlaud, G.J., Gaboriaud, C.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 2.80 Å
• R-Value Free: 0.269 
• R-Value Work: 0.198 
• R-Value Observed: 0.203 

Literature

Monomeric structures of the zymogen and active catalytic domain of complement protease c1r: further insights into the c1 activation mechanism

Budayova-Spano, M., Grabarse, W., Thielens, N.M., Hillen, H., Lacroix, M., Schmidt, M., Fontecilla-Camps, J., Arlaud, G.J., Gaboriaud, C.

(2002) Structure 10: 1509-1519

• PubMed: 12429092 
• DOI: 10.1016/s0969-2126(02)00881-x
• Primary Citation of Related Structures:  
  1MD8, 1MD7


• PubMed Abstract: 
  

C1r is the serine protease (SP) that mediates autoactivation of C1, the complex that triggers the classical complement pathway. We have determined the crystal structure of two fragments from the human C1r catalytic domain, each encompassing the second complement control protein (CCP2) module and the SP domain. The wild-type species has an active structure, whereas the S637A mutant is a zymogen. The structures reveal a restricted hinge flexibility of the CCP2-SP interface, and both are characterized by the unique alpha-helical conformation of loop E. The zymogen activation domain exhibits high mobility, and the active structure shows a restricted access to most substrate binding subsites. Further implications relevant to the C1r self-activation process are derived from protein-protein interactions in the crystals.

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Organizational Affiliation: 

LCCP, Institut de Biologie Structurale Jean-Pierre Ebel, CEA-CNRS, 41 rue Jules Horowitz, Grenoble, France.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
C1R COMPLEMENT SERINE PROTEASE	A	329	Homo sapiens	Mutation(s): 0  Gene Names: C1R EC: 3.4.21.41
Find proteins for P00736 (Homo sapiens) Explore P00736  Go to UniProtKB:  P00736
NIH Common Fund Data Resources
PHAROS:  P00736

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 2.80 Å
• R-Value Free: 0.269 
• R-Value Work: 0.198 
• R-Value Observed: 0.203 
• Space Group: C 1 2 1

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 112.911	α = 90
b = 49.459	β = 106.19
c = 77.249	γ = 90

Software Package:

Software Name	Purpose
DENZO	data reduction
SCALA	data scaling
AMoRE	phasing
CNS	refinement
CCP4	data scaling

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2002-08-07 
• Released Date: 2003-08-07 
Deposition Author(s): Budayova-Spano, M., Grabarse, W., Thielens, N.M., Hillen, H., Lacroix, M., Schmidt, M., Fontecilla-Camps, J., Arlaud, G.J., Gaboriaud, C.

Revision History 

• Version 1.0: 2003-08-07
  Type: Initial release
  
• Version 1.1: 2008-04-28
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance