cysteine

noun

cys·​te·​ine ˈsi-stə-ˌēn 

: a crystalline sulfur-containing amino acid C₃H₇NO₂S readily oxidizable to cystine

Examples of cysteine in a Sentence

Recent Examples on the Web

To promote these reactions, alternative meat developers will add browning agents, including specific amino acids such as cysteine, methionine, and lysine, sugars, and the vitamin thiamin. —Discover Magazine, 28 Nov. 2024

The body naturally produces taurine from the amino acid cysteine. —Jillian Kubala, Rd, Health, 5 Nov. 2024

Previous work from Devaraj’s lab showed the amino acid cysteine, which was also likely prevalent during our planet’s youth, can act like a chemical clamp, fastening certain precursor molecules together to yield lipids. —Bymitch Leslie, science.org, 30 Oct. 2024

While spice allergies are rare, a certain enzyme found in ginger (cysteine proteinase GP-1) may trigger allergic reactions in some people. —Lauren O'Connor, Ms, Health, 16 Sep. 2024

Word History

Etymology

International Scientific Vocabulary, from cystine + -ein

First Known Use

1884, in the meaning defined above

Medical Definition

cysteine

noun

cys·​teine ˈsis-tə-ˌēn 

: a sulfur-containing amino acid C₃H₇NO₂S occurring in many proteins and glutathione and readily oxidizable to cystine

—abbreviation Cys