cysteine
noun
Simple meaning
A sulphur-containing nonessential amino acid C₃H₇NO₂S found in most animal proteins.
Pronunciation
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sisteenSay the bold part a little louder.
IPA pronunciation (US)
ˈsɪstin
This word is pronounced essentially the same in American and British English, so one transcription covers both.
IPA (International Phonetic Alphabet) is a standard way of writing speech sounds.
Definition
Everyday modern meanings first, grouped by part of speech.
noun
biochemistry
A sulphur-containing nonessential amino acid C₃H₇NO₂S found in most animal proteins; it readily oxidizes to cystine.
biochemistry
An amino acid containing sulfur that is found in most proteins; oxidizes on exposure to air to form cystine
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