Intracellulars

Question 1

what is zipper mechanism?

Answer 1

receptor ligand interaction that allows entry into cells

• Internalin is the protein
• Essential for lysteria

Question 2

what is trigger mechansim?

Answer 2

form of macropinocytosis

T3SS

Question 3

name obligate intracellulars

Answer 3

chlamydia
coxiella
Ehrlichia
rickettsia
M. Leprasae

Question 4

name facultative intracellulars

Answer 4

M. tb
Nocardia
Salmonella
Shigella
Bartonella
Listeria
Legionella
Brucella
francisella

Question 5

NADPH oxidase

Answer 5

forms on wall of phagolysosome and makes superoxide
Hydrogen peroxide
Hydroxyl radical
creates host damage

Question 6

Host

• antimicrobial proteins (defensins, Phospholipase, Lysozyme)
• upregulate ferritin
• NRAMP transporter that pumps iron out of phagosome

Answer 6

-Catalase, interfere with expression of NADPH oxidase subunits
-siderophores to compete w/ ferritin
NRAMP homologs

Question 7

fusogenic

Answer 7

coxiells burnetti

-allows vacuole to mature and fuse with lysosome

Question 8

Non-fusogenic

Answer 8

TB,
Listeria-er,
Chlamydia-golgi
-non-maturing vacuole, doesnt acidify

Question 9

which organsim survives in RBC’s

Answer 9

bartonella

Question 10

how do aminoglycosides work

Answer 10

charges compoinds that cant cross membranes
they rely on pinocytosis
listeria can remain in cytosol (out of aminoglycoside reach)

Question 11

Products of the inflammatory response of host cells
can lessen the antimicrobial activity of antibiotics
Nitric oxide produced by IFN-γ
-activated macrophages
prevents killing of

Answer 11

intracellular Listeria , and Salmonella

by aminoglycosides and β-lactams