Which pathogen and its associated virulence factor are mismatched?

• A. Streptococcus pyogenes – M protein
• B. Staphylococcus aureus – Capsule
• C. Escherichia coli – Lipopolysaccharide (LPS)
• D. Clostridium botulinum – Botulinum toxin

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the concept of virulence factors, which are molecules produced by pathogens that contribute to their ability to cause disease by helping them invade the host, evade the immune system, or damage host tissues.
2. Step 2: Review the common virulence factors associated with each pathogen listed: Streptococcus pyogenes is known for the M protein, which helps it evade phagocytosis; Escherichia coli produces lipopolysaccharide (LPS), a component of its outer membrane that triggers strong immune responses; Clostridium botulinum produces botulinum toxin, a potent neurotoxin.
3. Step 3: Identify the mismatch by examining Staphylococcus aureus and its known virulence factors. While S. aureus does have a capsule, it is not its primary or most characteristic virulence factor. Instead, S. aureus is more famously associated with virulence factors such as protein A, coagulase, and various toxins.
4. Step 4: Conclude that the mismatch is 'Staphylococcus aureus – Capsule' because the capsule is not the defining or most notable virulence factor for this pathogen compared to the others listed.
5. Step 5: Summarize that the other pairs correctly match pathogens with their key virulence factors, confirming the mismatch in the given options.