Methionine

From Citizendium, the Citizens' Compendium

	Main Article	Talk	Related Articles  [?]	Bibliography  [?]	External Links  [?]
	This is a draft article, under development and not meant to be cited but you can help to improve it. These unapproved articles are subject to a disclaimer. [edit intro]

(CC) Image: David E. Volk
Methionine, a common amino acid.

Methionine, abbreviated Met or M, is one of the twenty common -amino acids used by living organisms to build proteins. Methionine and cysteine are the only amino acids that contain sulfur. The DNA codon for methionine is the "start" codon for protein synthesis, so all protein synthesis starts with a methionine on the N-terminus of proteins. Methionine also plays a role in the transfer of methyl groups within cells.