Bacteria are everywhere. Some are beneficial to us, and some harmful. Before the past decade, scientists believed that bacteria mostly worked individually. Scientists were unaware of the communication techniques bacteria have between each other. Today, with much credit given to scientist Bonnie Bassler, we are beginning to understand the communication efforts of bacteria. In the interview/article
"Bacteria Talk", she explains how this communication, called quorum sensing, works.
In general, she studies how bacterial cells can "talk" to each other through chemicals and how they can form large groups that function in unison. As bacteria divide and grow, each releases small amounts of chemicals called auto-inducers. With just a few bacteria releasing this, the molecule floats away, but when there is a large amount of the molecule present, all the bacteria start grabbing onto it with their receptors. The bacteria recognize the other cells and change their gene expression to be more compatible and in unison with each other. Bassler says that "essentially quorum sensing allows bacteria to be multi cellular."
Bassler started her observations and experiments using a harmless marine bacterium that produces bioluminescence called Vibrio harveyi. These bacteria make enzymes that produce photons of glowing blue light. Bassler used their visual aids to help observe the way they chemically communicated. Eventually, it was Woody Hastings who made the observation that when the bacterium was diluted down to only a few cells, the bacterium did not produce light. However, when a greater number of cells were added, they started producing light together.
Bassler is working on important next steps in quorum sensing. She is trying to find out if it is possible to control quorum sensing, and if it can be useful in things like antibiotics. It is possible that scientists could figure out how to use this idea to control the natural bacteria that is in and on each human as well. There are millions of bacteria that help in the digestion, on the skin, and throughout the whole body. If we could control those bacteria, we could better protect ourselves from the bacteria and viruses that make us sick. Bassler's dream is to create an anti-quorum sensing drug. She loves her work and enjoys the students she works with to accomplish this goal and many others.
