Front | Virulence factors of S. pyogenes? |
---|---|
Back | M protein: • the major virulence factor - if absent is non-virulent • adherance to host cells and phagocytosis inhibition • antigenic, but mimics human tissues • immune response can cross react with human tissues, causing rheumatic fever,rheumatic heart disease, glomerulonephritis Capsule: • inhibits phagocytosis • made from hyaluronic acid • indistinguishable from mammalian hyaluronic acid • poor immunogen Fibrils (AKA fimbriae, pilus, pili), Lipoteichoic acid, F protein • for attachment to host cells • fibrils support M protein, other proteins Streptococcal Pyrogenic Exotoxins (SPEs) • superantigens • massive non-specific T cell activation • cytokine storm, systemic inflammation • causes systemic symptoms of ― toxic shock ― necrotizing fasciitis ― scarlet fever Enzymes • Streptolysins: lyse human cells • Streptokinases: breakdown clots • Proteases: breakdown tissues • DNAses: breakdown pus |
Learn with these flashcards. Click next, previous, or up to navigate to more flashcards for this subject.
Next card: Reservoir s pyogenes upper respiratory tract urt
Previous card: Group identifying features streptococcus pyogenes characteristic beta haemolytic
Up to card list: Microbiology - Streptococcus and Enterococcus