n :  a crystalline sulfur-containing essential amino acid C₅H₁₁NO₂S that occurs in the L-form as a constituent of many proteins (as casein and egg albumin), that is important esp. as a source of sulfur for the biosynthesis of cystine and as a source of methyl groups for transmethylation reactions (as in the biosynthesis of choline, creatine, and adrenaline), and that is used as a dietary supplement for human beings and their domestic mammals and poultry and in the treatment of fatty infiltration of the liver - see MEONINE  .
 
 
 
Published under license with Merriam-Webster, Incorporated.  © 1997-2024.