Quorum sensing

Question 1

Summarize what quorum sensing is

Answer 1

Quorum sensing is a way for bacteria to detect population density and regulate gene expression accordingly

Question 2

Why is synchronization in microbial communities important?

Answer 2

Synchronization in microbial communities allows genes to be expressed collectively, creating a stronger effect. Ex. a single bacterium expressing virulence factors or bioluminescence may have little impact, but when many bacteria express these genes at the same time, the effect is amplified and more noticeable

Question 3

What do gram negative bacteria use as an autoinducer?

Answer 3

Acyl-homoserine lactones

Question 4

What do gram positive bacteria use as an autoinducer?

Answer 4

Modified peptides

These peptides are small and are species-specific

Question 5

What are the four steps of quorum sensing?

Answer 5

1. Bacteria produce and release autoinducers.2. As they reproduce, autoinducer levels increase. 3. Once a threshold is reached, bacteria sense it.
2. Gene expression (like bioluminescence) is activated.