Tyrosine

tyrosine /ty·ro·sine/ (Tyr) (Y) (ti´ro-sen) a naturally occurring, nonessential amino acid present in most proteins; it is a product of phenylalanine metabolism and a precursor of thyroid hormones, catecholamines, and melanin.

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ty·ro·sine (tr-sn)

n. Abbr. Tyr

A white crystalline amino acid that is derived from the hydrolysis of proteins such as casein and is a precursor of epinephrine, thyroxine, and melanin.

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Tyrosine

A protein building block found in a wide variety of foods that is used by the body to make melanin.

Mentioned in: Albinism

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tyrosine (tīˑ·r·sēn),

n an amino acid involved in the synthesis of neurotransmitters; has other functions. Has been used to treat sleep disorders, enhance cognitive function, and alleviate symptoms of ADD. No known precautions. Also called
L-tyrosine.

Chemical structure of tyrosine.

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tyrosine (Tyr) (tī´rsēn´),

n an amino acid synthesized in the body from the essential amino acid phenylalanine. Tyrosine is found in most proteins and is a precursor of melanin and several hormones, including epinephrine and thyroxine.

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tyrosine, tyrosin

Tyr; a naturally occurring amino acid present in most proteins; it is a product of phenylalanine metabolism and a precursor of melanin, catecholamines and thyroid hormones.

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tyrosine hydroxylase

an oxidase which converts tyrosine to dopa.

tyrosine tolerance test

used as a test of liver function but about 85% of liver parenchyma must be lost before the test gives a positive reaction.