limulus clotting factor _overbar_C_;
factor C;
limulus factor C
Class
Hydrolases;
Acting on peptide bonds (peptidases);
Serine endopeptidases
Reaction(IUBMB)
Selective cleavage of -Arg103!Ser- and -Ile124!Ile- bonds in limulus clotting factor B to form factor _overbar_B_. Cleavage of -Pro-Arg! bonds in synthetic substrates
Comment
From the hemocyte granules of the horseshoe crabs Limulus and Tachypleus. Factor C is activated by Gram-negative bacterial lipopolysaccharides and chymotrypsin. Inhibited by antithrombin III. In peptidase family S1 (trypsin family)
Muta T, Miyata T, Misumi Y, Tokunaga F, Nakamura T, Toh Y, Ikehara Y, Iwanaga S
Title
Limulus factor C. An endotoxin-sensitive serine protease zymogen with a mosaic structure of complement-like, epidermal growth factor-like, and lectin-like domains.
Further studies on lipopolysaccharide-sensitive serine protease zymogen (factor C): its isolation from Limulus polyphemus hemocytes and identification as an intracellular zymogen activated by alpha-chymotrypsin, not by trypsin.