Metioniinin

Metioniini is an alpha-amino acid with the formula CH3SCH2CH2CH(NH2)COOH. It is one of the proteinogenic amino acids, meaning it is one of the 20 standard amino acids that are incorporated into proteins during translation. Metioniini is classified as an essential amino acid, which means the human body cannot synthesize it and must obtain it through the diet. Its side chain contains a sulfur atom, making it a thioether.

In biological systems, metioniini plays several crucial roles. It is often the first amino acid incorporated into a new polypeptide chain during protein synthesis, recognized by a specific initiator tRNA. Metioniini is also a precursor to other important molecules, including S-adenosylmethionine (SAM), a universal methyl group donor essential for numerous biochemical reactions, and cysteine, another sulfur-containing amino acid. Additionally, metioniini is involved in the synthesis of glutathione, a key antioxidant.

Dietary sources of metioniini are abundant in protein-rich foods such as meat, fish, eggs, dairy products, and nuts. In plant-based diets, grains and legumes are also significant sources. Deficiency in metioniini can lead to various health issues, although it is relatively uncommon in individuals with a balanced diet. Research continues to explore the diverse functions and implications of metioniini in human health and metabolism.