X-ray diffraction
3Å resolution

Cobra Venom Factor (CVF) in complex with human factor B


Function and Biology Details

Reaction catalysed:
Cleavage of Arg-|-Ser bond in complement component C3 alpha-chain to yield C3a and C3b, and Arg-|- bond in complement component C5 alpha-chain to yield C5a and C5b.
Biochemical function:
Biological process:
Cellular component:

Structure analysis Details

Assemblies composition:
hetero tetramer (preferred)
hetero octamer
Entry contents:
4 distinct polypeptide molecules
Macromolecules (5 distinct):
Cobra venom factor alpha chain Chains: A, F
Molecule details ›
Chains: A, F
Length: 627 amino acids
Theoretical weight: 69.58 KDa
Source organism: Naja kaouthia
  • Canonical: Q91132 (Residues: 23-649; Coverage: 39%)
Sequence domains:
Structure domains:
Cobra venom factor gamma chain Chains: B, G
Molecule details ›
Chains: B, G
Length: 252 amino acids
Theoretical weight: 28.42 KDa
Source organism: Naja kaouthia
  • Canonical: Q91132 (Residues: 733-984; Coverage: 16%)
Sequence domains: Alpha-2-macroglobulin family
Structure domains:
Cobra venom factor beta chain Chains: C, H
Molecule details ›
Chains: C, H
Length: 379 amino acids
Theoretical weight: 43.63 KDa
Source organism: Naja kaouthia
  • Canonical: Q91132 (Residues: 1264-1642; Coverage: 23%)
Sequence domains:
Structure domains:
Complement factor B Chains: D, I
Molecule details ›
Chains: D, I
Length: 741 amino acids
Theoretical weight: 83.19 KDa
Source organism: Homo sapiens
Expression system: Homo sapiens
  • Canonical: P00751 (Residues: 26-764; Coverage: 100%)
Gene names: BF, BFD, CFB
Sequence domains:

Ligands and Environments

Carbohydrate polymer : NEW Components: NAG
2 bound ligands:
No modified residues

Experiments and Validation Details

Entry percentile scores
X-ray source: ESRF BEAMLINE ID23-1
Spacegroup: P212121
Unit cell:
a: 134.026Å b: 136.975Å c: 283.74Å
α: 90° β: 90° γ: 90°
R R work R free
0.19 0.189 0.243
Expression system: Homo sapiens