Toxins

Question 1

Clostridium diphtheriae

Answer 1

Diphtheria toxin: Inactivates EF-2

Question 2

Pseudomonas

Answer 2

Exotoxin A: inactivates EF-2 (like diphtheria toxin)

Question 3

Shigella

Answer 3

Shiga toxin - inactivates 60S ribosome by removing adenine from rRNA

Question 4

EHEC

Answer 4

Shiga-like toxin: inactivates 60S ribosome by removing adenine from rRNA

Question 5

What toxins can cause HUS?

Answer 5

Shiga and shiga-like toxin (Shigella and EHEC)

Question 6

ETEC

Answer 6

Heat Labile - increases cAMP (increases Cl secretion and causes watery diarrhea)

Heat Stable - increases cGMP (decreases NaCl resorption and causes watery diarrhea)

Question 7

Anthrax

Answer 7

Edema factor: acts like AC and increases cAMP and causes Cl secretion and causes edema associated with anthrax

Question 8

Cholerae

Answer 8

Cholera toxin: permanently activates AC and increases Cl secretion –> watery diarrhea

Question 9

Bordatella Pertussis

Answer 9

Pertussis toxin: Activates AC vi Gi inactivation –> impairs phagocytosis

Question 10

Tetanus

Answer 10

Cleaves SNARE: inhibits GABA and glycine release –> RIGID paralysis (esp. lockjaw)

Question 11

Botulism

Answer 11

Cleaves SNARE: inhibits Ach releas –> FLACCID paralysis

Question 12

Clostridium perfringens

Answer 12

Alpha toxin: phospholipase that degrades tissue –> GAS GANGRENE

Question 13

Strep pyogenes

Answer 13

Streptolysin O: Degrades cell membrane –> lyses RBCs (ASO Abs dxes rheumatic fever)

Question 14

What two organisms cause toxic shock syndrome? What do these toxins do?

Answer 14

S. aureus: TSST-1

Strep pyogenes: exotoxin A

These toxins bind MHC II and b-subunit of TCR and activate all the T cells –> LOTS of IFNy and IL-2 –> SHOCK

Question 15

All gram- organisms have what toxin? What does it cause?

Answer 15

LPS in their outer membrane: causes ENDOTOXIN:

Edema
Nitric oxide
D (DIC/Death)
Outer membrane
Tnf-a
O-antigen (neisseria)
eXtremely heat-stable
IL-1
Neutriophil chemotaxis

Question 16

What is bacterial transformation?

Answer 16

Ability to take up naked DNA in environment

ShiN

Question 17

What is bacterial conjugation?

Answer 17

Bacterial “sex” transfer of genetics via pilli

Question 18

What is bacterial transposition?

Answer 18

Segments of DNA “jump” from one location to another inside a bacterium

Question 19

What is bacterial transduction?

Answer 19

Bacteriophage transfers genetic material from one bacterium to another

Question 20

What cells must undergo transduction to become toxic?

Answer 20

ABCDE

shigA-like toxin (EHEC)
Botulinum toxin
Cholera toxin
Diphtheria toxin
Eryhtrogenic toxin of strep pyo