A patient with a severe Streptococcus pyogenes infection is treated with a thrombolytic agent derived from the bacteria. Which virulence factor of S. pyogenes activates plasminogen to dissolve fibrin clots, facilitating bacterial spread?
- A Streptodornase
- B Streptokinase ✓
- C Hyaluronidase
- D Streptolysin O
Correct answer: B. Streptokinase
Explanation
Streptokinase activates plasminogen to plasmin, which dissolves fibrin clots and aids bacterial spread. Streptodornase degrades DNA in pus. Hyaluronidase breaks down hyaluronic acid in connective tissue. Streptolysin O is a hemolysin that stimulates ASO antibody production. Streptokinase is the specific fibrinolytic enzyme.
Reference: Ananthanarayan and Panicker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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