lysine

American  

[lahy-seen, -sin] / ˈlaɪ sin, -sɪn /

noun

Biochemistry.

1. a crystalline, basic, amino acid, H 2 N(CH2 ) 4 CH(NH2 )COOH, produced chiefly from many proteins by hydrolysis, essential in the nutrition of humans and animals. Lys; K

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lysine British  

/ -sɪn, ˈlaɪsiːn /

noun

1. an essential amino acid that occurs in proteins

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lysine Scientific  

/ lī′sēn′ /

1. An essential amino acid. Chemical formula: C ₆ H ₁₄ N ₂ O ₂ .

2. See more at amino acid

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Etymology

Origin of lysine

First recorded in 1890–95; lys- + -ine ²

Example Sentences

"It was very surprising to find three lysine sites on three different proteins that correlate so highly with disease state."

From Science Daily • Mar. 12, 2026

One metabolite, or product, of lysine produced during this process is called pipecolic acid, and another, produced at a later step, is called N-hydroxypipecholic acid.

From Salon • Mar. 5, 2025

Non-susceptible species lack lysine at this position, which has a large side chain; macaques instead have asparagine, which contributes to HBV resistance.

From Science Daily • Dec. 3, 2024

The nonsticky, vegan lip treatments are meant to heal lips via shea butter, jojoba oil and lysine.

From Los Angeles Times • Mar. 14, 2024

Maize lacks digestible niacin, the amino acids lysine and tryptophan, necessary to make proteins and diets with too much maize can lead to protein deficiency and pellagra, a disease caused by lack of niacin.

From "1491" by Charles C. Mann