EC Number   |
Activating Compound |
Reference |
|---|
   3.4.21.47 | factor C |
acts as an LPS-responsive C3 convertase on the surface of invading Gram-negative bacteria in the initial phase of horseshoe crab complement activation. The proteolytic activity of factor C on the surface of Escherichia coli is essential for the deposition of C3b |
699342 |
| 3.4.21.47 | mannan-binding lectin |
binding to O antigen-specific oligosaccharides derived from Salmonella sp. corresponding to serogroup C, and efficient support of component C3 deposition in the absence of C2, C4, or the associated serine protease 2 |
669628 |
| 3.4.21.47 | human complement factor H-related protein 4 |
CFHR 4, two isozymes A and B of 86 and 45 kDa from plasma, domain structure, overview. The protein belongs to the factor H family of plasma glycoproteins that are composed of short consensus repeat (SCR) domains. It activates complement by serving as a platform for the assembly of alternative pathway C3 convertase via its interaction with C3b protein. CFHR4 binds C3b via its C-terminus, and it lacks SCRs homologous to the complement inhibitory domains of factor H and has no significant complement regulatory activities. In contrast to the complement inhibitor factor H, CFHR4 acts as an enhancer of opsonization by promoting complement activation |
732056 |
| 3.4.21.47 | more |
complement activation via the lectin pathway on zymosan particles is at least 4times more efficient than via the classical pathway on sheep erythrocytes coated with antibody. Every C4b deposited via the lectin pathway is capable of forming a convertase in contrast to only one of four C4b molecules deposited via the classical pathway. Rate of formation of lectin pathway C3/C5 convertases depends on the activation of C4 and C2 by MASP-2 |
698871 |
| 3.4.21.47 | properdin |
facilitates AP complement activation by stabilizing the C3 convertase C3bBb, essential for AP complement activation induced by bacterial lipopolysacharide (LPS) and lipooligosacharide (LOS) and other AP complement activators |
683294 |
| 3.4.21.47 | factor B |
generation of the AP C3-convertase initiates by the binding of factor B to C3b to form the proconvertase, C3bB. Factor B undergoes a dramatic conformational change upon binding to C3b, it binds near the C345C domain in C3b. Factor B-D279G mutant promotes high-affinity C3b-binding and is correctly cleaved by factor D in the C3bB proenzyme to generate a very stable, functionally-active, AP C3-convertase C3bBb |
701017 |
| 3.4.21.47 | more |
high surface density of complement component C3b is critical for the enzyme activity |
753082 |
| 3.4.21.47 | zymosan |
it is capable of activating the classical pathway as well as the alternative pathway, when the classical pathway is blocked, mechanism, overview |
732572 |
| 3.4.21.47 | mannan-binding lectin |
mannan-binding lectin (MBL) promotes activation of complement component C3 through the combined action of MBL-associated serine proteases MASP-1 and MASP-2 without appreciable involvement of the alternative pathway |
680169 |
| 3.4.21.47 | mannan-binding lectin |
mannan-binding lectin (MBL) promotes activation of complement component C3 through the combined action of MBL-associated serine proteases MASP-1 and MASP-2 without appreciable involvement of the alternative pathway, experimental conditions described |
680169 |
