L-Cysteine hydrochloride monohydrate, USP, suitable for cell cultureL Cysteine (Cys) is a semi essential proteinogenic sulfur containing amino acid. It provides the disulfide linkage in proteins and in involved in the transport of sulfur. L Cysteine is involved in the formation of hydrogen sulfide that functions as a signaling molecule. L Cysteine hydrochloride monohydrate has been used as a component of yeast dropout media for culturing yeasts. Purity: 98. 5 101. 0% Impurities: endotoxin, tested Source: non animal