Last reviewed 02/2022

Methionine is a sulphur-containing amino acid in which the R group in the general formula NH2-CHR-COOH is the group -CH2-CH2-S-CH3. It is an essential amino acid.

Methionine can be minimally synthesized from homocysteine in conjunction with methylcobalamin.

Methionine can be further metabolized to:

  • formate, important for:
    • purine synthesis } required for DNA synthesis
    • thymidylate synthesis }
    • folate production
  • S-adenosylmethionine; important in neuronal metabolism