Trimethylglycine (TMG)

Trimethylglycine (TMG) is an organic compound that occurs in plants. TMG is an organic osmolyte that occurs in high concentrations (10s of millimolar) in many marine invertebrates, such as crustaceans and molluscs. It serves as a potent appetitive attractant to generalist carnivores such as the predatory sea-slug Pleurobranchaea californica. TMG is an important cofactor in methylation, a process that occurs in every cell of mammals to synthesize and donate methyl groups (CH3) for other processes in the body. These processes include the synthesis of neurotransmitters such as dopamine, serotonin. Methylation is also required for the biosynthesis of melatonin and the electron transport chain constituent coenzyme Q10. Trimethylglycine is an N-trimethylated amino acid. This quaternary ammonium exists as the zwitterion at neutral pH.