au·​to·​in·​duc·​er | \ ˌȯ-tō-ˌin-ˈd(y)ü-sər How to pronounce autoinducer (audio) \
plural autoinducers

Definition of autoinducer

: a molecule produced and secreted by bacteria that when present at a threshold concentration in a population of bacteria signals genetic expression in the same bacteria from which it was produced When a crowd of bacteria and their autoinducers become dense enough, the lights in all the bacteria switch on at once.— Wendy Orent, Discover, July/August 2009 The synchronous response of bacterial populations to autoinducers confers a form of multicellularity to bacteria.— Andrew Camilli and Bonnie L. Bassler, Science, 24 Feb. 2006

Note: Autoinducers are involved in the quorum sensing used by some bacteria to detect their population density and coordinate group actions (such as the formation of biofilms).

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First Known Use of autoinducer

1968, in the meaning defined above

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The first known use of autoinducer was in 1968

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Cite this Entry

“Autoinducer.” Dictionary, Merriam-Webster, Accessed 26 Jun. 2022.

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