Lysine: Sources, Metabolism, Physiological Importance, and Use as a Supplement Levocarnitine, commonly known as L Carnitine, is a naturally occurring compound that the body produces from the amino acids lysine and methionine. It plays a critical role in energy production by transporting fatty EuRho Vital L Carnitin + L Arginin EuRho Vital Source Naturals L Proline L Lysine, 275 mg 120 Tablets Smith's Food and Drug