A molecular model of glycine, the smallest of the 20 common amino acids that can be synthesized in the human body, but can also be found in certain food supplements. Glycine acts as a building block for other proteins, and is also an inhibitory neurotransmitter in the central nervous system. Commercially, glycine has been utilized as a sweetener in certain foods, as well as a buffering agent in antacids and analgesics. Atoms are coloured dark grey (carbon), light grey (hydrogen), red (oxygen) and blue (nitrogen).