IdeS, a secreted proteinase of Streptococcus pyogenes, is bound to a nuclease at the bacterial surface where it inactivates opsonizing IgG antibodies.

ABSTRACT: The important bacterial pathogen Streptococcus pyogenes secretes IdeS (immunoglobulin G-degrading enzyme of S. pyogenes), a proteinase that cleaves human immunoglobulin G (IgG) antibodies in the hinge region resulting in Fc (fragment crystallizable) and F(ab')₂ (fragment antigen-binding) fragments and protects the bacteria against phagocytic killing. Experiments with radiolabeled IdeS and flow cytometry demonstrated that IdeS binds to the surface of S. pyogenes, and the interaction was most prominent in conditions resembling those in the pharynx (acidic pH and low salt), the habitat for S. pyogenes. SpnA (S. pyogenes nuclease A) is a cell wall-anchored DNase. A dose-dependent interaction between purified SpnA and IdeS was demonstrated in slot binding and surface plasmon resonanc

SUBMITTER: Frick IM 

PROVIDER: S-EPMC10654033 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature