Acetyl L Carnitine The Role of L Carnitine in Kidney Disease and Related Metabolic Dysfunctions L carnitine is primarily synthesized in the liver from the amino acids lysine and methionine through a series of four enzymatic reactions, with the liver and kidneys converting the precursor butyrobetaine into active Carnitine: Genetic Variants Affecting Mitochondrial Energy and Health Metabolic Maintenance Acetyl L Carnitine