IUBMB Enzyme Nomenclature


Accepted name: coagulation factor XIa

Reaction: Selective cleavage of ArgAla and ArgVal bonds in factor IX to form factor IXa

Other name(s): blood-coagulation factor XIa; activated blood-coagulation factor XI; activated plasma thromboplastin antecedent

Comments: In peptidase family S1 (trypsin family), and one of the γ-carboxyglutamic acid-containing blood coagulation factors. The proenzyme factor XI is activated by factor XIIa

Links to other databases: BRENDA, EXPASY, KEGG, MEROPS, Metacyc, PDB, CAS registry number: 37203-61-5


1. Kurachi, K. and Davie, E.W. Human factor XI (plasma thromboplastin antecedent). Methods Enzymol. 80 (1981) 211-220

2. Cho, K., Tanaka, T., Cook, R.R., Kisiel, W., Fujikawa, K., Kurachi, K. and Powers, J.C. Active-site mapping of bovine and human blood coagulation serine proteases using synthetic peptide 4-nitroanilide and thio ester substrates. Biochemistry 23 (1984) 644-650. [PMID: 6370301]

3. Fujikawa, K., Chung, D.W., Hendrickson, L.E. and Davie, E.W. Amino acid sequence of human factor XI, a blood coagulation factor with four tandem repeats that are highly homologous with plasma prekallikrein. Biochemistry 25 (1986) 2417-2424. [PMID: 3636155]

[EC created 1978]

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