Endotoxins And Exotoxins

Front 1

Endotoxins are the cumpulsory component of gram ______ bacteria.

Back 1

Structural component of gram negative bacteria

Front 2

Gram ______ bacteria have a unique outer cytoplasmic membrane made of what?

Back 2

Negative; phospholipid bilayer, myristic acid (2 make up Lipid A)

Front 3

T/F: myristic acid are unique to endotoxins.

Back 3

True.

Front 4

Lipopolysacharides are made up of what components?

Back 4

myristic acids + polysacharides

Front 5

What is the toxic component of LPS? Is it strongly immunogenic?

Back 5

Lipid A. Strongly pathogenic but weakly immunogenic! So we can't make Abs against it to prevent the next attack but it will wreak havoc on our tissues.

Front 6

What is responsible for endotoxic septic shock? Common?

Back 6

Lipid A! Most common cause of death in intensive care units in the US.

Front 7

Polysacharide component of LPS is highly ________ but weakly ________.

Back 7

highly immunogenic; weakly pathogenic

Front 8

Abs against polysaccharide components of LPS help us how?

Back 8

to determine which type of gram - bacteria! Every gram - bact has different shaped polysaccharides. These polysaccharides are also called "O" angigen.

Front 9

Define Bacteremia

Back 9

Occurs daily! Very common! Simple presence of bacteria in the blood. Before they multiply and damage our cells.

Front 10

Define Septicemia

Back 10

When bacteria are actively multiplying and using your blood as a blood culture.

Front 11

What happens in heavy gram neg septicemia

Back 11

When you give antibiotics, bacteria explode and release all endotoxins which can activate macrophages/endothelial cells and cause severe immune response! leading to death sometimes.

Front 12

What are exotoxins? Who produces them?

Back 12

Actively secreted toxic molecules that can travel away from the local bacterial infection. (example: pharyngitis infection where exotoxins are produced can travel to heart and damage it without even infecting it!)

Produced by BOTH gram + and - bacteria

Front 13

What is a good morphological indicator if something is gram +?

Back 13

IF it has a lot of peptidoglycan and no outer membrane.

Front 14

How do some bacteria get away with secreting exotoxins without even showing the immune system?

Back 14

Some bacteria have injectosomes that inject them directly into the cell

Front 15

Give an example of a bacteria in which some have injectosomes and some dont. Which ones are more virulent?

Other examples?

Back 15

Pseudomonas Aeruginosa. Ones with injectosomes are more virulent.

e. coli

salmonella

shigella

yesimia pestis

Front 16

What is the structural arrangement of exotoxins?

Back 16

Polypeptide protein molecules!

Front 17

Which toxin is heat labile? Exception?

Back 17

exotoxins. Endotoxins are heat stable

One exception ... enterotoxin produced by staphylococcus aureus. this exotoxin is heat stabile. So the heated food will not destroy them. It is a super angigen-->causing intense cytokine release and inflammation. These cytokines irritate the enteric NS that go to nausea and vomiting center making you puke!

Front 18

Exotoxins are immunogenic? Toxigenic?

Back 18

Both! Once you produce Anti-toxin Ab's against them you're immune system can handle them next time.

Front 19

Do we produce any Ab's against endotoxins or lipid A?

Back 19

Nope

Front 20

For which can we make anti-toxin vaccines?

Back 20

exotoxins

Front 21

How do we make the vaccine? What is a toxoid?

Back 21

we alter the toxin so that we get rid of the part that causes pathogenesis but still retains its immunogenicity. This is a toxoid.

Front 22

what is the structure of bacterial DNA?

Back 22

Circular, double stranded in one chromosome. They can also have plasmids

Front 23

What are bacteriophages

Back 23

viral structures that inject viral DNA into the bacteria and allow for integration of the genetic material.

Front 24

Genes for exotoxins can come from which 3 sources?

Back 24

Bacterial chromosome, bacterial plasmids, or viral bacteriophages

Front 25

Where are the genes responsible for making endotoxins?

Back 25

Must be present in bacterial chromosome (not plasmid). this is because endotoxins are structural components of the bacteria so they must be in the chromosome. They are integral to the structure.

Front 26

why do only some Diptheria bacteria have diptheria toxin?

Back 26

Because diptheria toxin comes from bacteriophages.

Front 27

Genes for cholera, botulinum toxins are found where?

Back 27

Cholera: bacteriophage sources within the bacteria

Botulinum both bacteriophages and plasmids

Front 28

_microgram of an exotoxin is enough to kill a person. How does this compare to endotoxins?

Back 28

1 microgram! Exotoxins are more pathogenic than endotoxins.

Front 29

Which toxin causes similar presentation regardless of the bacteria from which it came?

Back 29

endotoxins. Exotoxins can cause a wide variety of effects.