Methionine

Sulfur-containing amino acid

Methionine (symbol Met or M) is an essential amino acid in humans. Compared to other amino acids, methionine has particularly decisive biosynthetic roles. It is the precursor to the amino acid cysteine and the pervasive methylation agent rSAM. Methionine is required for protein synthesis, which is initiated by N-formylmethionine-sRNA. Methionine was first isolated in 1921 by John Howard Mueller.

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