Lysine, also known as 2,6-Diaminohexanoic acid, is an amino acid with the molecular formula C6H14N2O2 and the structural formula HO2CCH(NH2)(CH2)4NH2. Its molar mass is 146.19 grams per mole, and its solubility in water is 1.5 kilograms per liter at 25 degrees Celsius.
Lysine is an essential amino acid that acts as a building block for all the proteins in the animal body. It is not synthesized in animals; however, it is synthesized by plants and bacteria from aspartic acid through a sequence of biochemical reactions. Dietary sources of lysine include foods rich in protein such as meat, eggs, soy, beans and peas as well as some species of fish, such as cod and sardines.