plas·​mid | \ ˈplaz-məd \

Definition of plasmid

: an extrachromosomal ring of DNA especially of bacteria that replicates autonomously

Examples of plasmid in a Sentence

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But compared to modern African strains, the medieval strain is missing copies of six loci, mostly at a particular site on some plasmids. Kiona N. Smith, Ars Technica, "Ancient DNA reveals the secrets of a devastating European disease," 26 Sep. 2018 The researchers found that S. typhi had gained more resistance genes by acquiring a plasmid, a circular piece of DNA, from another bacterium (a process known as horizontal gene transfer). The Economist, "A strain of typhoid could become virtually untreatable," 26 Apr. 2018 Worse, the antibiotic-resistant DNA can be carried in little cassettes of genetic material called plasmids that bacteria can slip in their entirety to one another and to other species of bacteria. NBC News, ""Nightmare bacteria" are trying to spread in the U.S., CDC says," 3 Apr. 2018 Genetic sequencing revealed that a common, aggressive MDR typhoid strain called H58 interacted with another bacteria, likely E. coli, and acquired from it an additional DNA molecule, called a plasmid, that coded for resistance to ceftriaxone. Emily Baumgaertner, New York Times, "‘We’re Out of Options’: Doctors Battle Drug-Resistant Typhoid Outbreak," 13 Apr. 2018 To obtain appropriate plasmids the foundry’s customers may simply order parts from the library. The Economist, "The gene machineRobotic labs for high-speed genetic research are on the rise," 1 Mar. 2018 The genes comprising a potential circuit are then assembled into circular DNA molecules called plasmids. The Economist, "The gene machineRobotic labs for high-speed genetic research are on the rise," 1 Mar. 2018 The cells are subjected to electrical pulses that briefly open holes in their outer membranes, allowing the plasmids to flow in. Bradley J. Fikes,, "OncoSec Medical to hold stock offering," 31 Jan. 2018 When the plasmid in question contains drug-resistant genes, the gonorrheal bacteria acquiring it become resistant to antibiotics, too. Aneri Pattani, New York Times, "A Dangerous, ‘Silent Reservoir’ for Gonorrhea: The Throat," 31 July 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'plasmid.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of plasmid

1952, in the meaning defined above

History and Etymology for plasmid

plasma + -id entry 2

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Last Updated

24 Nov 2018

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The first known use of plasmid was in 1952

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plas·​mid | \ ˈplaz-məd \

Medical Definition of plasmid

: an extrachromosomal ring of DNA that replicates autonomously and is found especially in bacteria — compare episome

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