cysteine

American  

[sis-tee-een, -in] / ˈsɪs tiˌin, -ɪn /

noun

Biochemistry.

1. a crystalline amino acid, C 3 H 7 O 2 NS, a component of nearly all proteins, obtained by the reduction of cystine. Cys; C

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cysteine British  

/ -ɪn, ˈsɪstɪˌiːn /

noun

1. a sulphur-containing amino acid, present in proteins, that oxidizes on exposure to air to form cystine. Formula: HSCH 2 CH(NH 2 )COOH

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cysteine Scientific  

/ sĭs′tə-ēn′ /

1. A nonessential amino acid. Chemical formula: C ₃ H ₇ NO ₂ S.

2. See more at amino acid

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Other Word Forms

• cysteinic adjective

Etymology

Origin of cysteine

First recorded in 1880–85; alteration of cystine

Compare meaning

How does cysteine compare to similar and commonly confused words? Explore the most common comparisons:

• cysteine vs. cystine

Example Sentences

These included the amino acids cysteine and taurine, along with coenzyme M, which plays a key role in metabolism.

From Science Daily

Further experiments revealed that cysteine sets off a chain reaction that activates immune cells known as CD8 T cells.

From Science Daily

In the course of their experiments, the researchers treated cells with an antioxidant drug -- something that reduces ROS -- called N-acetyl cysteine and saw that this partially restored protein mobility.

From Science Daily

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.

From Salon

"It can modify proteins through a process called sulfhydration, where it modifies cysteine residues and can change their activity."

From Science Daily