phenylalanine

American  

[fen-l-al-uh-neen, -nin, feen-] / ˌfɛn lˈæl əˌnin, -nɪn, ˌfin- /

noun

Biochemistry.

1. a crystalline, water-soluble, essential amino acid, C 6 H 5 CH 2 CH(NH2 )COOH, necessary to the nutrition of humans and most animals, obtained chiefly from egg white or skim milk. Phe; F

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phenylalanine British  

/ ˌfiːnaɪlˈæləˌniːn, ˌfɛnɪl- /

noun

1. an aromatic essential amino acid; a component of proteins

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phenylalanine Scientific  

/ fĕn′əl-ăl′ə-nēn′ /

1. An essential amino acid. Chemical formula: C ₉ H ₁₁ NO ₂ .

2. See more at amino acid

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Etymology

Origin of phenylalanine

First recorded in 1880–85; phenyl + alanine

Example Sentences

The connection remained even after accounting for other related factors, including phenylalanine.

From Science Daily • Feb. 26, 2026

On these lines, they conducted a series of experiments by replacing phenylalanine and valine amino acid residues at specific positions in the structure of Ado, with various other amino acids.

From Science Daily • May 16, 2024

These metabolites include phenylalanine, aspartic acid and methanol.

From Salon • Jul. 14, 2023

These are people with an inherited disease called phenylketonuria or PKU, who are born unable to metabolise the phenylalanine that is released as aspartame is broken down.

From BBC • Jul. 13, 2023

The person must closely follow a strict diet that is low in phenylalanine to avoid symptoms and damage.

From Textbooks • Jun. 19, 2013