PDBe 2xwb

X-ray diffraction
3.49Å resolution

Crystal Structure of Complement C3b in complex with Factors B and D

Released:

Function and Biology Details

Reactions 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.
Selective cleavage of Arg-|-Lys bond in complement factor B when in complex with complement subcomponent C3b or with cobra venom factor.
Biochemical function:
Biological process:
Cellular component:

Structure analysis Details

Assembly composition:
hetero tetramer (preferred)
Entry contents:
4 distinct polypeptide molecules
Macromolecules (4 distinct):
Complement C3 beta chain Chains: A, C
Molecule details ›
Chains: A, C
Length: 642 amino acids
Theoretical weight: 71.15 KDa
Source organism: Homo sapiens
UniProt:
  • Canonical: NEW P01024 (Residues: 23-664; Coverage: 39%)
Gene names: C3, CPAMD1
Sequence domains:
Structure domains:
Complement C3b alpha' chain Chains: B, D
Complement factor B Chains: F, H
Molecule details ›
Chains: F, H
Length: 732 amino acids
Theoretical weight: 82.16 KDa
Source organism: Homo sapiens
Expression system: Homo sapiens
UniProt:
  • Canonical: NEW P00751 (Residues: 35-764; Coverage: 99%)
Gene names: BF, BFD, CFB
Sequence domains:
Structure domains:
Complement factor D Chains: I, J
Molecule details ›
Chains: I, J
Length: 228 amino acids
Theoretical weight: 24.42 KDa
Source organism: Homo sapiens
Expression system: Homo sapiens
UniProt:
  • Canonical: NEW P00746 (Residues: 26-253; Coverage: 98%)
Gene names: CFD, DF, PFD
Sequence domains: Trypsin
Structure domains: Trypsin-like serine proteases

Ligands and Environments


No modified residues

Experiments and Validation Details

Entry percentile scores
X-ray source: ESRF BEAMLINE ID23-1
Spacegroup: P1
Unit cell:
a: 108.275Å b: 135.775Å c: 149.975Å
α: 95.47° β: 110.69° γ: 113.39°
R-values:
R R work R free
0.192 0.189 0.244
Expression system: Homo sapiens