According to Britannica, Quorum sensing is a mechanism by which bacteria regulate gene expression in accordance with population density through the use of signal molecules. Quorum sensing allows bacteria populations to communicate and coordinate group behaviour and commonly is used by pathogens (disease-causing organisms) in disease and infection processes. Bacterial activity involving quorum sensing was first observed in the mid-1960s by Hungarian-born microbiologist Alexander Tomasz in his studies of the ability of Pneumococcus (later known as Streptococcus pneumoniae) to take up free DNA from its environment.
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