Extra Stuff

Question 1

What does a type III secretion system do?

Answer 1

Senses presence of eukaryotic organism and secretes effector proteins into the eukaryotic cell, and helps the pathogen to survive and escape an immune response

Question 2

What does amylovoran do?

Answer 2

It is an exopolysaccharide which makes Erwinia amylovora pathogenic by enabling it to penetrate host tissue and cause disease.
Without amylovoran the bacteria are unable to spread in plant vessels (Belleman and Geider, 1992)
Necessary for biofilm formation

Question 3

Quorum sensing

Answer 3

At low concentrations, LuxI makes AHL which diffuses away, never exceeding the threshold level so there is so expression
At high concentrations, AHL re-enters cells do the internal concentration is high. LuxR binds to AHL, activates transcription from lux-box promoters - lots of downstream expression of toxins etc.

Question 4

What does Hrp stand for

Answer 4

For hypersensitive response and pathogenicity

Question 5

Plasmodium

Answer 5

A megacell (multinucleate mass of cytoplasm with one cell membrane)

Question 6

Difference in defence pathways between necrotrophs and biotrophs

Answer 6

Necrotrophs: controlled by jasmonate- and ethylene- dependent host defence pathways
Biotrophs: controlled by salicylate- dependent host defence pathways

Question 7

Examples of hemibiotrophs

Answer 7

Phytophthora infestans

Magnaporthe grisea