Legionella

Question 1

What is the life cycle of Legionella pneumophila?

Answer 1

1. Replicate in amoebae (colonization)
2. Distribution and amplification via water
3. Transmission by aerosolization

Question 2

What is the life cycle of Legionella longbeachae?

Answer 2

1. Pine trees
2. Amplification and distribution in potting soil
3. Transmission by aerosolization

Question 3

The general architecture of type I secretion system?

Answer 3

ABC transporter, membrane fusion protein, outer membrane protein

Question 4

The general architecture of type II secretion system?

Answer 4

Outer membrane pore, inner membrane platform, pseudopilus

Question 5

The general architecture of type IV secretion system?

Answer 5

Basal body, needle, translocon

Question 6

What is the function of Dot/Icm in L. pneumophila?

Answer 6

Inject effector proteins into cell
Hijack host cell processes to create legionella containing vacuoles (defective organelle trafficking)
Prevent fusion with lysosomes to allow replication in macrophages (intracellular multiplication)

Question 7

What is the GNAT mechanism?

Answer 7

GNAT transfer an acetyl group (COCH3) to a substrate, usually a lysine, but could be another amine
Acetyl CoA acts as the acetyl donor

Question 8

What is the relevance of GNAT to VipF?

Answer 8

VipF contains a GNAT domain which can do this, effectively inactivating and hijacking host cells (to make legionella containing vacuoles)