Diphthine—ammonia ligase
In enzymology, a diphthine-ammonia ligase (, "diphthamide synthase", "diphthamide synthetase") is an enzyme that catalyzes the chemical reaction The 3 substrates of this enzyme are ATP, diphthine, and NH, whereas its 3 products are ADP, phosphate, and diphthamide. This enzyme belongs to the family of ligases, specifically those forming carbon-nitrogen bonds as acid-D-amino-acid ligases (peptide synthases). The systematic name of this enzyme class is diphthine:ammonia ligase (ADP-forming). Other names in common use include diphthamide synthase, and diphthamide synthetase.