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  

/ ˈtaɪrəˌsiːn, -sɪn, ˈtɪrə- /

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

But when the researchers examined the relationships more closely, tyrosine was the one that consistently stood out.

From Science Daily ● Sep. 6, 2026

The relationship also remained after the researchers accounted for phenylalanine and other related factors, strengthening the possibility that tyrosine itself may have an independent connection to aging.

From Science Daily ● Sep. 6, 2026

First, they looked for associations between blood concentrations of phenylalanine and tyrosine and outcomes related to death and predicted lifespan.

From Science Daily ● Sep. 6, 2026

The research was published in Aging-US titled "The role of phenylalanine and tyrosine in longevity: a cohort and Mendelian randomization study."

From Science Daily ● Sep. 6, 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