title: Neisseria gonorrhoeae and neisseria meningitidis: extracellular enzyme cleaves human immunoglobulin A.
abstract: The gonococcus and meningococcus, which infect human mucosal surfaces, elaborate a highly specific proteolytic enzyme which cleaves the immunoglobulin A1 subclass of the principal mucosal antibody, immunoglobulin A (IgA). The susceptible Pro-Thr bond lies in a unique region of the IgA heavy chain; the IgA2 subclass, lacking this peptide bond, is enzyme resistant.
mesh_terms: D006801:Humans; D007070:Immunoglobulin A / Q000378:metabolism*; D007071:Immunoglobulin A, Secretory / Q000378:metabolism; D009344:Neisseria gonorrhoeae / Q000201:enzymology* / Q000276:immunology; D009345:Neisseria meningitidis / Q000201:enzymology* / Q000276:immunology; D010447:Peptide Hydrolases / Q000378:metabolism*
chemical_list: D007070:Immunoglobulin A; D007071:Immunoglobulin A, Secretory; D010447:Peptide Hydrolases