CATH Classification

Domain Context

CATH Clusters

Superfamily 2.40.10.120
Functional Family Complement factor B

Enzyme Information

3.4.21.47
Alternative-complement-pathway C3/C5 convertase.
based on mapping to UniProt P00751
Cleavage of Arg-|-Ser bond in complement component C3 alpha-chain to yield C3a and C3b, and Arg-|-Xaa bond in complement component C5 alpha- chain to yield C5a and C5b.
-!- A bimolecular complex of complement fragment Bb with either C3b or cobra venom factor; Bb contains the active site. -!- Bb is formed by cleavage of proenzyme factor B by factor D. -!- Cleavage of complement component C5 requires additional C3b which binds C5 and renders it susceptible to cleavage by C3b,Bb complex. -!- C3b,Bb is stabilized in plasma by factor P. -!- Belongs to peptidase family S1.

UniProtKB Entries (1)

P00751
CFAB_HUMAN
Homo sapiens
Complement factor B

PDB Structure

PDB 2OK5
External Links
Method X-RAY DIFFRACTION
Organism Homo
Primary Citation
Factor B structure provides insights into activation of the central protease of the complement system.
Milder, F.J., Gomes, L., Schouten, A., Janssen, B.J., Huizinga, E.G., Romijn, R.A., Hemrika, W., Roos, A., Daha, M.R., Gros, P.
Nat.Struct.Mol.Biol.