2.3 Bacterial pathogens sedate host

Question 1

Plants recognize which bacterial molecules?

Answer 1

Cell wall components:
● Flagellin protein, Lipopolysaccharides

Enzymes:
● Elongation factor EF-Tu

These are PAMPs

Question 2

Recognition of PAMPs by receptors induces

Answer 2

PAMP-triggered immunity (PTI)

Question 3

Bacteria succeed by

Answer 3

Suppressing PTI via effectors

Question 4

Suppression of immune response results in

Answer 4

EFFECTOR-TRIGGERED SUSCEPTIBILITY (ETS)

Question 5

How do effectors get into host cytoplasm?

Answer 5

Effector proteins are
injected by a needle-like
structure (also referred to
as “translocon”) through
the host wall and plasma
membrane into the host
cytoplasm.

These are type III secretion effectors (T3SS)

Question 6

Main points

Answer 6

Plant pathogenic bacteria:

• Need to suppress plant defense
for successful invasion: “sedation”

• Inject effector proteins into host
cytoplasm using needle-like
protein complex (T3SS)

• T3SS sticks out from bacterial wall
and perforates the plant cell wall
and plant plasma membrane