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Flashcards in Microbial Toxins Deck (26):
1

Infectious diseases cause about ________ of deaths worldwide.

1/3

2

________ is the most toxic microbial toxin known.

Botulinum

3

Polysaccharides make lipid A _________.

soluble

4

Endotoxin can cause ___________.

(1) inflammation, by activating the complement cascade; (2) fibrinolysis, by activating Hagemen factor; (3) hypotension, by activating bradykinin (also through Hagemen); and (4) DIC, by activating TNF-alpha -> factor VII -> factor X

5

Hemolysins are often __________.

pore-forming toxins

6

Gram-positive bacteria tend to make ___________ more than Gram-negative bacteria.

pore-forming cytolysins

7

Superantigens can cause _____________.

toxic-shock syndrome and necrotizing fasciitis

8

Staphylococcus aureus and streptococcus pyogenes together produce __________.

more than 19 different superantigens

9

Diphtheria infection leads to ___________.

bull neck, conjunctivitis, myocarditis, and colonization of the pharyngeal membrane

10

How does diphtheria toxin kill cells?

It modifies EF-2 (elongation factor-2) and thereby inhibits protein synthesis.

11

Diphtheria is only taken up by ___________.

susceptible cells--those with the membrane receptor for diphtheria toxin (epidermal growth factor receptor, EGFR)

12

Diphtheria binds with its ___ subunit and kills with its ______ subunit.

B; A

13

________ treat diphtheria.

Anti-toxin and erythromycin

14

Diphtheria toxin and Pseudomonas aeruginosa exotoxin A both _________.

inhibit protein synthesis by transferring the ADP-ribose portion of NAD to EF-2

15

Although they do the same thing inside cells, diphtheria toxin and P. aeruginosa toxins _________.

are not cross-reactive; they have different antigenic regions and affect different cells based on membrane-receptor affinity

16

____________ all also inhibit protein synthesis, similar to diphtheria and P. aeruginosa toxin, but they do so by ________.

Shiga toxin, enterohemorrhagic E. coli toxin, and ricin; modifying the 60S subunit of eukaryotic ribosome

17

Type III secretion is ____________.

injection directly into host cells through needles; common in Gram-negative bacteria

18

Type VI secretion is _______________.

needle insertion into other bacteria

19

Botulinum toxin works on __________, while tetanus toxin works on _________.

motor neurons; spinal interneurons

20

Botulinum toxin is released by __________.

cell lysis

21

Some exotoxins that degrade the extracellular matrix are _________.

hyaluronidase, collagenase, elastase, and streptokinase

22

Although they both inhibit cell protein synthesis, diphtheria toxin and pseudomonas aeruginosa exotoxin act on ________.

different cells; PAE targets liver cells, and DT attacks heart, liver, and kidney cells

23

The exotoxins that affect intracellular signaling pathways are __________.

Vibrio cholerae, E. coli, anthrax, C. diff, and B. pertussis

24

Tetanus toxin inhibits ___________.

VAMP (and the subsequent release of vesicles)

25

Staphylococcal enterotoxins and streptococcal exotoxins are both _________.

superantigens

26

Diphtheria does not leave the __________.

respiratory tract or skin--only its toxin does

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