en·​do·​nu·​cle·​ase | \ ˌen-dō-ˈnü-klē-ˌās How to pronounce endonuclease (audio) , -ˌāz, -ˈnyü-\

Definition of endonuclease

: an enzyme that breaks down a nucleotide chain into two or more shorter chains by cleaving the internal covalent bonds linking nucleotides — compare exonuclease

Examples of endonuclease in a Sentence

Recent Examples on the Web

Xofluza interferes with a protein inside the flu virus called polymerase acidic endonuclease, which helps stop the virus from replicating, Dr. Adalja explains. Korin Miller, SELF, "What You Need to Know About Xofluza, the New Flu Medicine," 26 Oct. 2018 Humans don’t make UV endonuclease, either; researchers found it in a bacterium called Micrococcus luteus. Robbie Gonzalez, WIRED, "DNA-Repairing Sunscreen: Legit or Not?," 2 July 2018 Oftentimes those sequences were flanked by a set of genes coding for a class of strand-cutting enzymes called endonucleases. Megan Molteni, WIRED, "The WIRED Guide to Crispr," 27 Apr. 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'endonuclease.' 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 endonuclease

1962, in the meaning defined above

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Time Traveler for endonuclease

The first known use of endonuclease was in 1962

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More Definitions for endonuclease


en·​do·​nu·​cle·​ase | \ -ˈn(y)ü-klē-ˌās, -ˌāz How to pronounce endonuclease (audio) \

Medical Definition of endonuclease

: an enzyme that breaks down a nucleotide chain into two or more shorter chains by cleaving the internal phosphodiester bonds — see restriction endonuclease — compare exonuclease

More from Merriam-Webster on endonuclease

Britannica.com: Encyclopedia article about endonuclease

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formidable, illustrious, or eminent

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