Diadenosine hexaphosphate hydrolase (ATP-forming) (EC 220.127.116.11, Ndx1) is an enzyme with systematic name P1,P6-bis(5'-adenosyl)hexaphosphate nucleotidohydrolase (ATP-forming). This enzyme catalyses the following chemical reaction
(1) P1,P6-bis(5'-adenosyl)hexaphosphate + H2
(2) P1,P5-bis(5'-adenosyl)pentaphosphate + H2
ATP + ADP
(3) P1,P4-bis(5'-adenosyl)tetraphosphate + H2
ATP + AMP
The enzyme requires the presence of the divalent cations (Mn2+, Mg2+, Zn2+, and Co2+).