autoinducer

noun

au·​to·​in·​duc·​er ˌȯ-tō-ˌin-ˈd(y)ü-sər 

plural autoinducers

microbiology

: 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).

Word History

First Known Use

1968, in the meaning defined above

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