Elliott has made several substantial and impressive contributions to biochemistry. Glutamine synthetase was discovered by him and was the first enzyme to be discovered of the group, now known as the synthetases, which catalyse the syntheses of peptide bonds coupled with the breakdown of ATP. This discovery also constituted the first example in which a carboxyl group of an amino acid took part in such a synthetic reaction. The enzyme system which synthesises taurocholic acid via cholyl-CoA was also discovered by Elliott, as was the synthesis of nicotinuric acid by liver mitochondria. The elucidation of the reactions involved in urea synthesis was partly due to his discovery of an enzyme system which condensed arginine and fumarate to form arginosuccinate. His most recent work on glycine and threonine metabolism, in which a new metabolic cycle was proposed, is extremely elegant and provides a raison-d'etre for the existence of glyoxalase and D-lactate dehydrogenase in animal tissues.