5 Gram Positive Rods (Infectious Bacterial Agents)

Question 1

Corynebacterium diptheriae

Answer 1

• Produces AB TOXIN that inactivates EF-2 elongation factor, preventing protein synthesis and causing cell death.
• Pleomorphic gram positive rods
• Spread by aerosol droplets

Question 2

Corynebacterium diptheriae (Clinical Significance)

Answer 2

• Upper respiratory tract infection causes a PSEUDOMEMBRANE

- Vaccine that neutralizes toxin: Tdap

Question 3

Bacillus anthracis

Answer 3

• GRAM POSITIVE RODS that can form ENDOSPORES
• Infections through skin abrasions and inhalation anthrax
• Used as bioterrorism attack: (CATEGORY A AGENT)

Question 4

Bacillus anthracis (Clincal/Virulence Significance)

Answer 4

• Cutaneous: 20% mortality; Pulmonary: 100% mortality
• Capsule (phagocytic)
• Exotoxins: Edema toxin and lethal toxin (both AB toxins)

Question 5

Listeria monocytogenes

Answer 5

• GRAM POSITIVE RODS
• Found in many food products (ice cream, cheese, ground meat, poultry)
• Infects PREGNANT WOMEN, FETUSES, NEWBORNS, AND IMMUNOCOMPROMISED

Question 6

Listeria monocytogenes (Clinical Significance)

Answer 6

• Causes MENINGITIS and SEPTICEMIA
• Listeriolysin O: bacteria escapes phagosome
• Control of actin filaments: propel through host cell and penetrates neighboring cell.