microbial toxins

Question 1

Toxin actions

Answer 1

1. spread
2. damage cell wall
3. cytokin production
4. protein synthesis
5. intracellular pathways
6. Inhibit release of NT

Question 2

What toxin help spread? (5)

Answer 2

Hyaluronidase
Collagenase
Elastase
Deoxyribonuclease
Streptokinase

Question 3

LIst 2 toxin damage cell walls

Answer 3

Hemolysins

cytolysins

Question 4

How does toxin damage cell walls?

Answer 4

insert into membrane –> complex –> more/lyse

Question 5

Name 2 cytokine production toxin

Answer 5

pryogenic exotoxins

Superantigens

Question 6

How do super antigens work?

Answer 6

Bind MHC Class II and Vb on T cell –> antigen independent activation

Question 7

2 toxin that inhibits protein synthesis

Answer 7

Diptheria toxin (and pseudomonas exotoxin)
Shiga toxins

Question 8

Diptheria toxin targets ___?

Answer 8

EF2 (inactivates)

ADP transfer from NAD to EF2

Question 9

Shiga toxin targets ___?

Answer 9

28S (part of 60s)

Removes Adenine from 28S

Question 10

Name the 6 toxin that modify intracellular signaling pathways

Answer 10

Heat labile of vibrio cholerae/E coli
Pertussis toxin
Heat stable enterotoxin ST1 Ecoli
Anthrax edema factor
Anthrax lethal factor
C. difficile toxin A & B

Question 11

C. Difficile toxin A causes ____

Answer 11

Diarrhea

Question 12

C difficile toxin B affects ____?

Answer 12

Rho family GTPase (actin cytoskeleton)

glucosyl transferase: UDP - glu –> rho

Question 13

Anthrax lethal factor targets ___?

Answer 13

(endopeptidase cleaves) MAP kinase kinase proteins (inactive signal transduction)

Question 14

Anthrax edema factor causes

Answer 14

increase cAMP

adenylate cyclase toxin - need Ca2+ and calmodulin

Question 15

Adenylate cyclase toxin requires _____ and _____ to activate

Answer 15

Calcium and calmodulin

Question 16

Heat stable enterotoxin 1 (ST1) Ecoli targets is a ______ ______ and causes ______ to increase and ________

Answer 16

granylate cyclase; cGMP; secretory diarrhea

Question 17

Pertussis toxin and heat labil enterotoxin (cholera and Echoli) is a ______________

Answer 17

ADP ribosyltransferase

Question 18

Pertussis toxin causes G_ to be ______, which causes _____

Answer 18

Gi to be inactivated –> increase cAMP (increase secretion)

Question 19

Cholera and heat labil ecoli toxin (enterotoxin) causes G_ to be ______, which causes _____

Answer 19

Gs to be active –> increase cAMP (increase secretion)

Question 20

Name 2 toxin that inhibits release of neurotransmittors

Answer 20

botulinum toxin + tetanus toxin

Question 21

botulinum toxin + tetanus toxin are ____________?

Answer 21

zinc - dependent endopeptidase

Question 22

botulinum toxin + tetanus toxin inactivates _______ which causes the inability to _______

Answer 22

SNARE; neuroexocytosis

Question 23

botulinum toxin causes ___ paralysis, vs tetanus toxin causes ___ paralysis

Answer 23

flaccid; spastic

Question 24

botulinum toxin + tetanus toxin acts where? (different places)

Answer 24

Bot: at myoneural junction - inhibits release of Ach
Tet: at spinal cord - inhibits inhibitory interneurons

Question 25

Toxins act _______ or on _______

Answer 25

extracellulary; plasma membrane

Question 26

Toxins are typically bi functions... what are the two domains and fcn?

Answer 26

subunit A: Active | subunit B: binding

Question 27

Toxins usually enter target cells by _______

Answer 27

endocytosis

Question 28

Antitoxin functions?

Answer 28

bind to toxin - prevent toxicity - neutralization

Question 29

Antitoxin does NOT do what? (2)

Answer 29

1. prevent infection by bacteria | 2. reverse toxic effect

Question 30

Toxoids are derivatives of ____ and retains ______ but lack _____

Answer 30

toxins; immunogenicity; toxicity

Question 31

Toxoid used for

Answer 31

active immunization vaccine

Question 32

Passive immunization administrates _______ and are _____ protection against toxin/infectious agent

Answer 32

antibodies, temporary

Question 33

Immunotoxin/hormonotoxins are

Answer 33

hybrid molecule: Toxin fragment + ligand

Question 34

Uses of Immunotoxins

Answer 34

cancer, autoimmune, etc