As means of communication increase between humans, such as text messaging and social media, bacteria and potentially human cells are communicating with each other to come up with a plan of action. Researchers at Rice and Tel Aviv University have been investigating the pathways in which these cells communicate information about cell stress, the colony density, and possible plans of neighboring cells. Research in this area could result in many medical applications.
José Onuchi, Ph. D., explained to Science Daily that “Using this form of cell-to-cell communication, colonies of billions or trillions of bacteria can literally reach a consensus on actions that impact people.”
Onuchi gave an example of a group of harmless bacteria gathering on the skin. These bacteria may one day send chemical signals to each other and decide that there are enough of them to join together and cause an infection. This network of infection causing bacteria is known as a biofilm. Biofilms are responsible for making many chronic diseases difficult to treat. Urinary tract infections and cystic fibrosis are two examples of biofilms forming and causing treatment difficulties.
Bacillus subtilis has been the focus of the research to try to understand this network of communication. B. subtilis is a bacterium found in the soil and responds to stressful environmental conditions by either turning themselves into spores or transforming into a competency state, which is protective state that won’t be harmed by the outside conditions. These two states allow the bacteria to survive in harsh or stressful situations. In the spore state the bacteria discard half of their DNA into the environment and create a thick armor like shell that allows them to survive for years, but they are able to return to normal bacteria. The competency state is more for short term stressful situations. The risk with the competency state is if the conditions don’t improve quickly the bacterium could die before being able to change into a spore.
Onuchi explained that most bacteria will become spores in poor environmental conditions but about 1-2% “see” that the other bacteria are becoming spores and choose to take some of their discarded DNA and enter competency.
Onuchi believes that the bacteria make their decisions on “game theory”, which is a concept used in math to analyze conflict and cooperation. Onuchi explained to Science Daily “…the bacteria have to weigh the pros and cons of their decisions. The bacteria make a decision based not only on what it knows about its own stress and environment, but it also has to think about what the other bacteria might do.”
So how can research on bacteria living in the soil and their communication and decision making processes benefit the human population in anyway? One answer: cancer treatment.
As the research progresses with the bacteria , human cells are becoming the main focus. Onuchi is specifically looking at communication that could result in uncontrolled division and growth, AKA the cause of cancer. One of the main causes of cancer is just that, the uncontrolled division and growth of cells. The current thought is that similarly to the bacteria discussed earlier, the human cells may be chit-chatting amongst themselves and sending chemical signals to one another that cause the cancer to grow. Not only could this be the starting point of cancer, but could also explain the spreading of cancer to other parts of the body, also known as metastasis.
Onuchi described the medical treatment benefits of identifying this process to Science Daily.
“It would open the door to developing better drugs that have fewer side effects. For example, once we get a handle on this process, we might block the specific chemical messages that signal a tumor to grow, developing a medicine that wouldn’t affect other body processes, reducing or eliminating side effects.”
The researchers are hopeful, but like most growing areas of science, cannot make any promises based on their research. The identifying of the possibility of this communication pathway and understanding the complexities of the bacteria communication is key, however, in starting the in depth look at human cells.
American Chemical Society (ACS). “Bacteria use chat to play the ‘prisoner’s dilemma’ game in deciding their fate.” ScienceDaily, 27 Mar. 2012. Web. 29 Mar. 2012.