Bugging the Bugs

Microbial Geneticist Bonnie Bassler:

Investigating Bacterial Communications


Bonnie Bassler Is a Spy

Bassler, a bacterial geneticist at Princeton University, eavesdrops on bacteria.

The bacteria Bassler investigates

Question:

What word describes bacteria that glow in the dark?


Answer: Bioluminescent

Luminescent bacteria can make seafood glimmer blue-green.

Next time you see raw fish, turn out the lights and check out the glow!


Vibrio harveyi bacteria (V. harveyi)

Only glow when they are in a sufficiently large group (known as a quorum)


Quorum Sensing


How Harmful Bacteria Use Quorum Sensing

These changes culminate in an infection that can ambush and overwhelm our immune system defenses.

The bacteria appear relatively innocuous as they quietly grow in number.

When their population reaches a certain level, instant changes occur in their


More About Quorum Sensing

  1. Bacteria leak a chemical into their surroundings.

  1. Independent, solitary bacterial cells become part of a large, multicellular organism, known as biofilm, when the amount of a certain chemical reaches a particular level.

What do we call such chemicals?

Give an example of a common biofilm.


V. harveyi Are Bilingual

V. harveyi communication systems


The Chain of Command in Bacterial Communication


Decoy Molecules?

AI-2 contains the element boron

AI-2 and similar boron-containing molecules made in the laboratory could serve as decoys to subvert virulence and other quorum-sensing behaviors

Autoinducer 2 may hold the key to disrupting quorum-sensing.


Research Applications

In what ways might the knowledge that Bassler has gained about bacterial quorum-sensing be applied in human medicine?