phenylalanine

American

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

noun

Biochemistry.

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

phenylalanine British

/ ˌfiːnaɪlˈæləˌniːn, ˌfɛnɪl- /

noun

an aromatic essential amino acid; a component of proteins

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

phenylalanine Scientific

/ fĕn′əl-ăl′ə-nēn′ /

An essential amino acid. Chemical formula: C ₉ H ₁₁ NO ₂ .
See more at amino acid

Etymology

Origin of phenylalanine

First recorded in 1880–85; phenyl + alanine

Example Sentences

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See Examples For:

phenylalanine

Plants produce anthocyanins through a series of enzyme driven reactions that begin with the amino acid phenylalanine.

From Science Daily ● Jun. 15, 2026

The paper, titled "The role of phenylalanine and tyrosine in longevity: a cohort and Mendelian randomization study," examined whether levels of these nutrients in the blood are connected to lifespan.

From Science Daily ● Feb. 26, 2026

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

Untreated, this can lead to an accumulation of phenylalanine, which can lead to intellectual disabilities.

From Textbooks ● Feb. 14, 2019

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023