IgA-specific serine endopeptidase

IgA-specific serine endopeptidase (commonly known as IgA protease) is a bacterial enzyme secreted by several pathogenic organisms, including Neisseria gonorrhoeae, Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae. It selectively cleaves human immunoglobulin A subclass 1 (IgA1) in the proline-rich hinge region of its heavy chain, but does not affect IgA2. By degrading IgA1, a key antibody in mucosal immunity, the enzyme disrupts local immune defense, facilitating bacterial adherence and colonization of mucous membranes. This activity may play a central role in the virulence of these pathogens; however, the enzyme varies in specificity among species and there are no current small-molecule therapeutics directly targeting it

Other names

IgA proteaseImmunoglobulin A proteaseIgA1 proteaseIgA proteinaseIgA-specific proteinaseImmunoglobulin A proteinaseIgAse Pro-Pro-Y-Pro

Bacterial IgA-specific serine endopeptidase cleaves IgA1 at Pro-|-Xaa bonds in the hinge region, abrogating the immunological function of IgA1 antibodies and weakening mucosal immunity, thus promoting bacterial survival and colonization