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

The researchers suggest that individuals with high tyrosine levels might benefit from dietary adjustments.

From Science Daily • Feb. 26, 2026

However, after deeper analysis, only tyrosine showed a consistent and potentially causal relationship with reduced life expectancy in men.

From Science Daily • Feb. 26, 2026

Phenylalanine and tyrosine are amino acids that play important roles in metabolism and brain activity.

From Science Daily • Feb. 26, 2026

Although this study did not directly test tyrosine supplements, the findings raise questions about its long term impact on health and lifespan.

From Science Daily • Feb. 26, 2026

Hydrolysis by acids indicates that it contains leucine and tyrosine, two amino-acids which are constituents of proteins, along with other bodies of unknown composition.

From The Chemistry of Plant Life by Thatcher, Roscoe Wilfred