tyrosine

American  

[tahy-ruh-seen, -sin, tir-uh-] / ˈtaɪ rəˌsin, -sɪn, ˈtɪr ə- /

noun

Biochemistry.

1. a crystalline amino acid, HOC 6 H 4 CH 2 CH(NH2 )COOH, abundant in ripe cheese, that acts as a precursor of norepinephrine and dopamine. Tyr; Y

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tyrosine British  

/ -sɪn, ˈtɪrə-, ˈtaɪrəˌsiːn /

noun

1. an aromatic nonessential amino acid; a component of proteins. It is a metabolic precursor of thyroxine, the pigment melanin, and other biologically important compounds

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tyrosine Scientific  

/ tī′rə-sēn′ /

1. A nonessential amino acid. Chemical formula: C ₉ H ₁₁ NO ₃ .

2. See more at amino acid

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Etymology

Origin of tyrosine

1855–60; < Greek tȳrós cheese + -ine ²

Example Sentences

See Examples For:

tyrosine

Gut bacteria create these compounds when they digest the amino acids tyrosine and phenylalanine, but the resulting metabolites can have very different effects on health.

From Science Daily ● Aug. 15, 2026

As a result, the findings should not be interpreted as proof that tyrosine supplements are harmful.

From Science Daily ● Jun. 15, 2026

Importantly, the researchers did not directly examine tyrosine supplements or test whether taking supplemental tyrosine shortens lifespan.

From Science Daily ● Jun. 15, 2026

However, after accounting for additional factors and conducting more detailed analyses, only tyrosine continued to show a consistent relationship with lifespan.

From Science Daily ● Jun. 15, 2026

Both the tyrosine and tryptophane may be either in the free state or in combination as polypeptid or peptone.

From The Elements of Bacteriological Technique A Laboratory Guide for Medical, Dental, and Technical Students. Second Edition Rewritten and Enlarged. by J. W. H. (John William Henry) Eyre