Glutamine is one of the 20 amino acids the standard genetic code

Glutamine (abbreviated as Gln or Q; the abbreviation Glx or Z represents either glutamine or glutamic acid) is one of the 20 amino acids encoded by the standard genetic code. Its side chain is an amide formed by replacing the side-chain hydroxyl of glutamic acid with an amine functional group. It can therefore be considered the amide of glutamic acid. Its codons are CAA and CAG.