Nε,Nε,Nε-Trimethyllysine chloride (Lys(Me)3-OH Chloride) is a methylated derivative of the amino acid lysine. It is a component of histone proteins, a precursor of carnitine and a coenzyme of fatty acid oxidation. Nε,Nε,Nε--Trimethyl-L-lysine residues are found in a number of proteins and are generated by the action of S-adenosyl-L-methionine on exposed lysine residues. When trimethyllysine is released from cognate proteins via proteolysis, it serves as a precursor for carnitine biosynthesis. Mitochondrial 6-N-trimethyllysine dioxygenase converts 6-N-trimethyllysine to 3-hydroxy-6-N-trimethyllysine as the first step for carnitine biosynthesis.