IUBMB Enzyme Nomenclature


Accepted name: complement subcomponent C

Reaction: Selective cleavage of Lys(or Arg)Ile bond in complement subcomponent C1s to form C (EC

Other name(s): activated complement C1r; C esterase; activated complement C1r

Comments: Activated from proenzyme C in plasma during activation of the complement system by the "classical" route. In peptidase family S1 (trypsin family)

Links to other databases: BRENDA, EXPASY, KEGG, MEROPS, Metacyc, PDB, CAS registry number: 80295-69-8


1. Sim, R.B. The human complement system serine proteases C and C and their proenzymes. Methods Enzymol. 80 (1981) 26-42. [PMID: 6281620]

2. Leytus, S.P., Kurachi, K., Sakariassen, K.S. and Davie, E.W. Nucleotide sequence of the cDNA coding for human complement C1r. Biochemistry 25 (1986) 4855-4863. [PMID: 3021205]

3. Müller-Eberhard, H.J. Molecular organization and function of the complement system. Annu. Rev. Biochem. 57 (1988) 321-347. [PMID: 3052276]

[EC created 1981]

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