GRAM POSITIVE COCCUS: PATHOGENECITY Flashcards
EXTRACELLULAR ENZYMES
Coagulase
Lipase
Hyaluronidase (Spreading Factor)
Staphylokinase
Nuclease (DNAse)
97% of Staphylococcus aureus
isolated in human produce the
enzyme
Coagulase
enzyme that reacts with the blood
factor in the plasma to initiate clot
formation
Coagulase
Coagulase enhance the deposition of the______around the organism to protect them from phagocytosis
fibrin
lipid – hydrolyzing enzyme
Lipase
counteracts the action of fatty substances secreted by the body
Lipase
help in the colonization of organism – oily
skin surfaces
Lipase
found in the intracellular ground
substance of connective tissue
Hyaluronidase (Spreading Factor)
promote invasion of organism by
digesting the intracellular ground
substance “glue” that binds connective tissue in host
tissue
Hyaluronidase (Spreading Factor)
that binds connective tissue in host
tissue
hyaluronidase
causes dissolution of clot – spread
infection further
Staphylokinase
Production by most strain of
Staphylococcus
Staphylokinase
heat – resistant protein
Nuclease (DNAse)
degrade nucleic acid DNA
Nuclease (DNAse)
most specific test for Staphylococcus
aureus
Nuclease (DNAse)
found in cell surfaces of _____ of
Staphylococcus aureus
Nuclease (DNAse) 90% - 96%
lyse RBC by destroying their membrane:
producing tissue damage and abscess formation
Hemolysins/Cytolytic Toxins
Types: a, β, , , P-V
Hemolysins/Cytolytic Toxins