Hydrolases;
Acting on peptide bonds (peptidases);
Serine endopeptidases
Reaction(IUBMB)
The primary cleavage site is at His67!Lys68 in human C5a with a minor secondary cleavage site at Ala58!Ser59
Comment
This enzyme is a surface-associated subtilisin-like serine peptidase with very specific substrate specificity. Virulent strains of streptococci, including Streptococcus pyogenes, can evade human detection and phagocytosis by destroying the complement chemotaxin C5a. Cleavage of human C5a by this enzyme reduces the ability of C5a to bind receptors on the surface of polymorphonuclear neutrophil leukocytes (PMNLs) and thereby abolishes its chemotactic properties [1,4]. Belongs in peptidase family S8A.