Parent Class:

EC-Numbers → 3 -- Hydrolases → 3.4 -- Acting on peptide bonds (peptide hydrolases) → 3.4.21 -- Serine endopeptidases

Synonyms: activated Christmas factor, blood-coagulation factor IXa, activated blood-coagulation factor IX, autoprothrombin II, blood platelet cofactor II, activated blood coagulation factor XI

Unification Links: BRENDA:3.4.21.22, ENZYME:3.4.21.22, IUBMB-ExplorEnz:3.4.21.22

Reaction:
factor X + H₂O → factor Xa

Enzymes and Genes:
[factor IX]-[factor XIII] complex: F8, F9 ( Homo sapiens )

Summary:
This enzyme, known as factor IXa, catalyzes the selective cleavage of an Arg-Ile bond in factor X to form factor Xa. A chymotrypsin homologue, and one of the γ-carboxyglutamic acid-containing blood coagulation factors. The proenzyme factor IX is activated by factor XIa. In peptidase family S1 (trypsin family).

Citations: [Fujikawa76, Davie79, Link83, Cho84]

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References

Cho84: Cho K, Tanaka T, Cook RR, Kisiel W, Fujikawa K, Kurachi K, Powers JC (1984). "Active-site mapping of bovine and human blood coagulation serine proteases using synthetic peptide 4-nitroanilide and thio ester substrates." Biochemistry 23(4);644-50. PMID: 6370301

Davie79: Davie EW, Fujikawa K, Kurachi K, Kisiel W (1979). "The role of serine proteases in the blood coagulation cascade." Adv Enzymol Relat Areas Mol Biol 48;277-318. PMID: 367103

Fujikawa76: Fujikawa K, Davie EW (1976). "Bovine factor IX (Christmas factor)." Methods Enzymol 45;74-83. PMID: 1012029

Link83: Link RP, Castellino FJ (1983). "Kinetic comparison of bovine blood coagulation factors IXa alpha and IXa beta toward bovine factor X." Biochemistry 22(17);4033-41. PMID: 6412750

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Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 46(D1):D633-D639 2018
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