Lecture 11

Question 1

Peptides and proteins don’t diffuse across membranes, this means they require a..

Answer 1

Porin, transporter molecule or carrier protein

Question 2

Increasing signal produces higher activation of response genes. This often occurs immediately, not gradually (non-linearly) this is called

Answer 2

Quorum sensing

Question 3

Quorum sensing (QS)

Answer 3

A form of density-dependent bacterial cell-cell communication mediating coordinated population wide changes in gene expression

Question 4

Quorum sensing is associated with

Answer 4

• Virulence
• Biolfilm formation
• Sporulation
• Antibiotic production
• Bioluminescence

Question 5

Bioluminescence in Vibrio fischeri:

Answer 5

A gram negative marine bacterium

• Use ATP to make luciferase a light producing molecule
• Found usually in association with other organisms
• Fish use it to attract prey, to find a mate or to avoid predation