EC 3.4.21.46     
Accepted name: complement factor D
Reaction: Selective cleavage of Arg┼Lys bond in complement factor B when in complex with complement subcomponent C3b or with cobra venom factor
Other name(s): C3 proactivator convertase; properdin factor D esterase; factor D; factor D (complement)
Comments: A component of the alternative pathway of complement activation. This reaction is analogous to the activation of complement component C2 by complement subcomponent C1s. In peptidase family S1 (trypsin family)
References:
1.  Reid, K.B.M., Johnson, D.M.A., Gagnon, J. and Prohaska, R. Preparation of human factor D of the alternative pathway of complement. Methods Enzymol. 80 (1981) 134–143. [PMID: 6918766]
2.  Müller-Eberhard, H.J. Molecular organization and function of the complement system. Annu. Rev. Biochem. 57 (1988) 321–347. [PMID: 3052276]
[EC 3.4.21.46 created 1981]