ENZYME entry: EC 3.4.21.45

Accepted Name
Complement factor I.
Alternative Name(s)
C3b inactivator.
C3b/C4b inactivator.
Complement component C3b inactivator.
Reaction catalysed
Inactivates complement subcomponents C3b, iC3b and C4b by proteolytic cleavage
Comment(s)
  • Cleavage of complement subcomponent C3b requires its binding to cofactor H or complement receptor CR1; cleavage of iC3b requires complement receptor CR1; cleavage of C4b requires C4b-binding protein.
  • Belongs to peptidase family S1.
Cross-references
PROSITEPDOC00124
BRENDA3.4.21.45
EC2PDB3.4.21.45
ExplorEnz3.4.21.45
PRIAM enzyme-specific profiles3.4.21.45
KEGG Ligand Database for Enzyme Nomenclature3.4.21.45
IUBMB Enzyme Nomenclature3.4.21.45
IntEnz3.4.21.45
MEDLINEFind literature relating to 3.4.21.45
MetaCyc3.4.21.45
UniProtKB/Swiss-Prot
P05156, CFAI_HUMAN;  Q61129, CFAI_MOUSE;  Q5R5A4, CFAI_PONAB;  
Q9WUW3, CFAI_RAT;  

View entry in original ENZYME format
View entry in raw text format (no links)

All UniProtKB/Swiss-Prot entries referenced in this entry, with possibility to download in different formats, align etc.
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 3.4.21.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 3.4.-.-
All ENZYME / UniProtKB/Swiss-Prot entries corresponding to 3.-.-.-