FA Exotoxins and Endotoxins Flashcards Preview

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Flashcards in FA Exotoxins and Endotoxins Deck (20):
1

What is the source of exotoxin

Certain species of some gram-positive and gram-negative bacteria.

2

What is the source of endotoxin

Outer cell membrane of most gram negative bacteria

3

Is exotoxin secreted from cell?

Yes!

4

Is endotoxin secreted from cell

No!

5

What is the chemistry of exotoxin?

Polypeptide

6

What is the chemistry of endotoxin?

Lipopolysaccharide (structural part of bacteria; released when lysed)

7

What is the location of exotoxin genes?

Plasmid or bacteriophage

8

What is the location of endotoxin genes?

Bacterial chromosome

9

What is the toxicity of exotoxin?

High! (fatal dose on the order of 1 microgram)

10

What is the toxicity of endotoxin?

Low (fatal dose on the order of hundreds of micrograms)

11

What are the clinical effects of endotoxin?

Fever, shock

12

What is the mode of action of endotoxin?

Induces TNF and IL-1

13

What is the antigenicity of exotoxin?

Induces high-titer antibodies called antitoxins

14

What is the antigenicity of endotoxin?

Poorly antigenic

15

Are there vaccines against exotoxins?

Toxoids used as vaccines

16

Are there vaccines against endotoxins?

No toxoids formed and no vaccine available

17

What is the heat stability of exotoxins?

Destroyed rapidly at 60 degrees Celsius, except staph enterotoxin

18

What is the heat stability of endotoxin?

Stable at 100 degrees C for 1 hour

19

What are the typical diseases you associate with exotoxin? (Name three)

Tetanus, botulism, diphtheria

20

What are the typical diseases you associate with endotoxin? (Name two)

Meningococcemia
Sepsis by gram negative rods