Legionella pneumophilia Flashcards
L.p is gram?
negative
What is it’s original host?
Protozoa/ameoba
What is it’s typical treatment
MQR
Macrolides
Quinolones
Rifamycin
Resistance is common
Macrolides
Quionolones
Rifamycin
Affect ribosome
Transcription
Transcription
How does is spread, what does it affect, what disease it causes?
Water droplets
Alveolar macrophages
Legionnaires disease
Has high bacterial load
Link between two hosts of l.p.
Bacteria survives in vacuoles in human macrophages or vacuoles
What is special about its genome?
Has >300 eucaryotic-like proteins.
As effector proteins (eps)
Or for T4SS secretion system
What gives membranes their own identify?
Lipid composition
How does L.p. enter the macrophage? What happens if it dosen’t work
Through T4ss, where a l.-containing-vacuole is created. without T4SS, hiding of LCVs dosen’t work
Why do LCVs hide by changing the lipud composition?
To evade immune response
HOW do LCV change its identity
Acquire ER membranes early in infection. Recruit ribosomes. Use for bacterial replication in LCV
Why is there >300 ep, though some are repetitive? Why does it make l.p eps more difficult to study?
Co-evolution with ameoba.
This makes knock-out studies of eps ineffective
How did the >300 ep get obtained
Horizontal transfer
How do eps manipulate host proteins (goes through proteosome)?
Promotes/deactivates degradation of host proteins in proteosome by ubitiquination/deubitiquination
Why is host protein degradation wanted by eps? What does it accidentally cause?
Make a.a for bacteria’s nutrition
Causes Golgi fragmentation and xenophagy
Why is host protein degradation prevented by eps?
Maintain homeostatis of host cell (prevent xenophagy and golgi fragmentation)
How do eps affect autophagy pathway (3)?
Activate inhibitor complexes
Cut complex required for membrane formation
Cut growing autophagosome (RavZ decongugates LC32-PE on growing autophagosome)
Why is the GTPase Rab1 important?
GTPase in ER to control processes for organelle function
How do eps target Rab1 GTPase (4)
Mimic GAP or GE
Add/remove AMP to make constantly active
Bind to PIs on ER membrane
Recruit ER membrane
How do compartments of ER attach via SNARES?
Donor and acceptor SNARE interact to allow membrane fusion
How are SNARES controlled?
By regulatory proteins (GTPases)
How do EPS affect Rab GTPase to obtain donor compartments?
EP SidM locks RAB1 in active state
Rab1+SidM connect to acceptor SNARE Stx3
Stx3 attachs to donor SNARE Sec22b
How does the LCV move?
Trafficking by microtubule formation
How does Leg1 interact with GTPases? (microtubules)
Binds to GTPase Ran to increase microtubule polymerisation for movement
