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

Tyrosine is especially notable because it helps the body produce neurotransmitters such as dopamine, norepinephrine, and epinephrine.

From Science Daily • Jun. 15, 2026

Tyrosine is especially notable because it helps produce neurotransmitters such as dopamine, which influence mood, motivation, and cognitive performance.

From Science Daily • Feb. 26, 2026

He owns a pet tortoise he named Tyrosine after an amino acid, and dreams of being an orthodontist after he retires from racing.

From The Wall Street Journal • Feb. 16, 2025

Tyrosine also helps to produce dopamine and norepinephrine, which many animals secrete in response to stress.

From Scientific American • Aug. 25, 2022

Tyrosine residues on the intracellular domain are then autophosphorylated, triggering a downstream cellular response.

From Textbooks • Jun. 9, 2022