What is Quorum Sensing and how do bacteria talk to each other?
The discovery that bacteria are able to communicate with each other changed our general perception of many single, simple organisms inhabiting our world. Instead of language, bacteria use signaling molecules which are released into the environment. As well as releasing the signaling molecules, bacteria are also able to measure the number (concentration) of the molecules within a population. Nowadays we use the term ‘Quorum Sensing’ (QS) to describe the phenomenon whereby the accumulation of signaling molecules enable a single cell to sense the number of bacteria (cell density). In the natural environment, there are many different bacteria living together which use various classes of signaling molecules. As they employ different languages they cannot necessarily talk to all other bacteria. Today, several quorum sensing systems are intensively studied in various organisms such as marine bacteria and several pathogenic bacteria.
Why do bacteria talk to each other?
(QS) enables bacteria to co-ordinate their behavior. As environmental conditions often change rapidly, bacteria need to respond quickly in order to survive. These responses include adaptation to availability of nutrients, defense against other microorganisms (biofilm formation) which may compete for the same nutrients and the avoidance of toxic compounds (biofilm formation) potentially dangerous for the bacteria. It is very important for pathogenic bacteria during infection of a host (e.g. humans, other animals or plants) to co-ordinate their virulence in order to escape the immune response of the host in order to be able to establish a successful infection. The University of Nottingham Quorum Sensing Research Group
From Dr. Ettinger’s Biofilm Protocol for Lyme and Gut Pathogens: Pathogenic bacteria known to reside in biofilms include: Borrelia burgdorferi, Escherichia coli, Candida albicans, Clostridium difficile, Clostridium perfringens, Helicobacter pylori, Klebsiella pneumoniae, Legionella pneumophila, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella typhimurium, Staphylococcus aureus, Staphylococcus epidermidis, and Vibrio cholerae. The number of human diseases shown to be associated with biofilms is expanding and includes chronic bacterial prostatitis, chronic rhinosinusitis, cystic fibrosis pneumonia, infective endocarditis, periodontitis, recurrent otitis media, and virtually all device and implant related infections. Strong evidence is also beginning to emerge for an etiologic role of pathogenic mucosal biofilms in gastrointestinal diseases, such as Irritable Bowel Disorders: Crohn’s disease and ulcerative colitis.