thre·​o·​nine | \ ˈthrē-ə-ˌnēn How to pronounce threonine (audio) \

Definition of threonine

: a colorless crystalline essential amino acid C4H9NO3

Examples of threonine in a Sentence

Recent Examples on the Web These essential amino acids are: histidine, isoleucine, leucine, lysine, methionine, phenyalinine, threonine, tryptophan and valine. Alyssa Jung, Good Housekeeping, 5 Oct. 2021 This insertion added the peptide GLTSKRN (glycine-leucine-threonine-serine-lysine-arginine-asparagine) between Spike protein positions 214 and 215. William A. Haseltine, Forbes, 28 Sep. 2021 The key dietary nutrients for collagen production include chromium, copper and zinc, Omega-3, silica, sulfur, vitamin C, iron, threonine, proline, and lysine—all of which are found in The Beauty Chef’s Collagen Inner Beauty Boost. April Long, Town & Country, 4 July 2021

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

First Known Use of threonine

1936, in the meaning defined above

History and Etymology for threonine

probably from threonic acid (C4H8O5)

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Time Traveler for threonine

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The first known use of threonine was in 1936

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Dictionary Entries Near threonine

threonic acid



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Cite this Entry

“Threonine.” Dictionary, Merriam-Webster, Accessed 28 Jun. 2022.

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More Definitions for threonine


thre·​o·​nine | \ ˈthrē-ə-ˌnēn How to pronounce threonine (audio) \

Medical Definition of threonine

: a colorless crystalline essential amino acid C4H9NO3 that is found in various proteins abbreviation Thr

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