Bacteria (细菌) play an important role in our lives. They can keep us alive as well as make us sick. It wasn't until fairly recently that we learned bacteria can communicate with one another.
In the 1960s, researchers found that a kind of bacteria called Vibrio fischeri(费氏弧菌) produced no light whenthey were alone, but that they exhibited great amount of light as the bacterial population grew to a certain number. How did this happen? How can Vibrio fischeri tell the difference between times when they're alone and times when they're in a community, and then all do something together?
Researchers found they talk to each other with a chemical language—signal molecules (信号分子). Vibrio fischeri makes signal molecules, and it also has a receptor on its surface that fits like a lock and key with a signal molecule. As the bacteria increase, more and more signal molecules are sent into the environment. When signal molecules increase to a certain amount, they lock down into those receptors and information comes into the bacteria, which tells them how many neighbors there are. As soon as they realize the population has hit the certain number, all of the bacteria behave as a group, making light together. In the past ten years researchers have found all bacteria have systems like this: they make and recognize chemical words, determine (判断) the size of the community, and carry out tasks that would be unsuccessful if a single one were to act alone. This process is called quorum sensing.
Most of the time, bacteria live with thousands of other species (种类) of bacteria. There has to be a language of interspecies communication. In fact, bacteria have another kind of signal molecule, which is the common language used by all species. Moreover, this kind of molecule has its own receptor. In this way, bacteria are able to count different populations, and then they decide what task to carry out depending on which species has the greatest population.
Knowing how bacteria communicate could influence how we fight disease. What if bacteria can't talk or hear? They won't recognize when there are enough bacteria and when to exhibit the group behavior to make us sick. Researchers are developing a method—to make molecules that look like the real ones and then they lock into the receptors to jam recognition of the real situation.
On the other hand, researchers also improve the conversation of the beneficial bacteria, so they can do things that we want them to do better than they would do on their own.
