Bonnie Bassler and others discovered quorum sensing in bacteria. Basically, bacteria excrete a chemical that lets others in its vicinity know how many bacteria are around. These “quorums” can be specific to a particular strain of bacteria, or they can be broader, allowing communication between bacteria to occur across species.
The Microbiota: Learning to Speak Germ-Man
Sebastian Wellford
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“Bonnie Bassler and others discovered quorum sensing in bacteria. Basically, bacteria excrete a chemical that lets others in its vicinity know how many bacteria are around. These “quorums” can be specific to a particular strain of bacteria, or they can be broader, allowing communication between bacteria to occur across species.”

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