pro·​line | \ˈprō-ˌlēn \

Definition of proline 

: an amino acid C5H9NO2 that can be synthesized by animals from glutamate

Examples of proline in a Sentence

Recent Examples on the Web

Collagen Peptides There are two amino acids in the protein collagen — proline and glycine — that are essential for the formation and repair of joints, bones, muscles, and tendons, Dr. Bowe says. Amy Capetta, Woman's Day, "5 Anti-Aging Supplements That May Actually Work," 16 Oct. 2018 The collagen found in our bodies is made up of several amino acids, including glycine, proline, hydroxyproline, and arginine. Elise Deming, Rdn, Ldn,, "What is collagen and why are people eating it?," 26 Feb. 2018

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

First Known Use of proline

1904, in the meaning defined above

History and Etymology for proline

German Prolin, contraction of Pyrrolidin pyrrolidine (C4H9N), from International Scientific Vocabulary pyrrole + -idine

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Last Updated

16 Nov 2018

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The first known use of proline was in 1904

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pro·​line | \ˈprō-ˌlēn \

Medical Definition of proline 

: an amino acid C5H9NO2 that can be synthesized by animals from glutamate abbreviation Pro

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