ATP is synthesized from ADP and Pi by ATPase Authored: Jassal, B, 2005-06-30 14:42:50 EC Number: 3.6.3.14 GENE ONTOLOGYGO:0006754 In the tight configuration, the beta subunit catalyzes the reaction of ADP + Pi to ATP + water. ATP is still tightly bound to the subunit at this stage. Pubmed4517936 Reactome Database ID Release 43164832 Reactome, http://www.reactome.org ReactomeREACT_190 ATPase-ADP and Pi complex ATPase-ATP complex