Frontiers Fatty acid oxidation in immune function Carnitine: Genetic Variants Affecting Mitochondrial Energy and Health Fatty Acid Metabolism Concise Medical Knowledge Role of carnitine in disease Nutrition & Metabolism Springer Nature Link The Carnitine Shuttle Cytosol Mitochondrial Fatty Acid Transport 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