coagulation factor XIIa

Function: - serine protease, proteolytically activates factor XI & prekallikrein - prekallikrein is cleaved by factor XII to form kallikrein, which then cleaves factor XII first to alpha-factor XIIa & then trypsin cleaves it to beta-factor XIIa - alpha-factor XIIa activates factor XI to factor XIa - selective cleavage of Arg-|-Ile bonds in factor VII to form factor VIIa & factor XI to form factor XIa - factor XII is activated by kallikrein in alpha-factor XIIa, which is then further converted by trypsin into beta-factor XIIa - alpha-factor XIIa is composed of the NH2-terminal heavy chain (coagulation factor XIIa heavy chain) & the COOH-terminal light chain (coagulation factor XIIa light chain), connected by a disulfide bond - beta-factor XIIa is composed of 2 chains linked by a disulfide bond, a light chain (beta-factor XIIa part 2), corresponding to the COOH-terminal light chain (coagulation factor XIIa light chain) & a nonapeptide (beta-factor XIIa part 1)

Related

coagulation cascade coagulation factor XII; Hageman factor; HAF; contains: coagulation factor XIIa heavy chain; beta-factor XIIa part 1; beta-factor XIIa part 2; coagulation factor XIIa light chain (F12)

General

coagulation factor serine protease

Properties

COMPARTMENT: plasma STATE: active state MOTIF: active site MOTIF: serine residue allosteric site FOR-BINDING-OF: complement C1 inhibitor

References

UniProt :accession P00748