Product Overview :
Significance of Measurement: Proteins contain three sulfur-containing amino acids: methionine, cystine, and cysteine (Cys). Cys is the only sulfur-containing amino acid with a thiol group and is derived from methionine. It plays a critical role in disulfide bond formation and often constitutes active sites of proteins. Cys also provides sulfhydryl groups for various physiological and biochemical reactions and is involved in skin metabolism and antioxidant defense.
Principle of Measurement: Cysteine reduces phosphotungstic acid to form tungsten blue, which exhibits a characteristic absorption peak at 600 nm. Cysteine content is calculated by measuring absorbance at 600 nm.
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