Bacterial effector proteins

Question 1

What is virulence?

Answer 1

Ability to cause damage to host

Question 2

What do virulence factors do?

Answer 2

Mediate infection. They are complex and expression is dynamic (made at different times)

Question 3

Pathogens that we are studying are intracellular?

Answer 3

Intracellular: FIRST internalized into compartments. can possibly escape

Question 4

Does Legionella pneumophilia break free from vacuole (LCV)

Answer 4

no

Question 5

What are the two types of virulence factors

Answer 5

Toxins and effectors

Question 6

Should virulence factors be too toxic?

Answer 6

No, it would lead to cell death therefore bacterial death

Question 7

Difference between toxins and effectors?

Answer 7

They are both secreted

Toxins - TOXIC effects
Effectors - NOT toxic on host.

Question 8

What do toxins do?

Answer 8

Damage host cell

Question 9

Effectors

Answer 9

They MANIPULATE host cell processes to mediate infection. Evolved to resemble host cell proteins. Dosen’t cause cell seath

They are SECRETED BY USUALLY A SINGLE SYSTEM

Question 10

Endo vs exotoxins

Answer 10

Endo: active when released during division/lysis

Exo: Proteins excreted to damage host cells. immunogenic

Question 11

What are GTPases?

Answer 11

Molecular switches. Is active when has GTP. Then, connects with host binidng partner to have cell effects.

Question 12

GEF and GAP?

Answer 12

Activiate and deactivate respectively

Question 13

What do Ras small GTPases do?

Answer 13

Control host processes (infection response, cytoskeleton, trafficking)

Question 14

Membrane identity is dependant on

Answer 14

membrane lipid compositions (different types of PIs)

Question 15

What do PIs on membranes do?

Answer 15

Help recruit host proteins for function (like trafficking, secretion, fusion)

Question 16

How do effectors (EPs) interact with PIS

Answer 16

Bind to manipulate PI content or manipulate host protein

Question 17

EPs 4 targets

Answer 17

Immunity
Cytoskeleton
Nuclear function
Autophagy

Question 18

Eps and immunity

Answer 18

Use teps to reverse or finely tune immune responses to benifit pathogen

Inactivate nFkB pathway to decrease inflmmation, but control as not to cause cell death

Question 19

Eps and cytoskeleton

Answer 19

use eps to induce uptake, cause cell-cell spread, etc.

Question 20

Eps and nuclear function

Answer 20

express proteins to bacterias benifit, manipulate cell cycle

Question 21

Eps and autophagy

Answer 21

Eps can make autophagy increase or decrease based on what’s wanted

Question 22

Definition of autophagy/xenophagy

Answer 22

Remove pathogens or unneeded cell components into lysosome