Catalyzes the hydrolysis of dATP, dADP and dAMP into dA (PubMed:33926954, PubMed:33893297). This step is essential for Z-genome synthesis (containing aminoadenine instead of adenine). Specifically removes dATP and its precursor dADP from the nucleotide pool of the host, preventing the incorporation of A into the phage genome and favoring the integration of the Z-base into the viral genome (PubMed:33926954, PubMed:33893297). dATP + H2O = 2'-deoxyadenosine + H(+) + triphosphate dADP + H2O = 2'-deoxyadenosine + diphosphate dAMP + H2O = 2'-deoxyadenosine + phosphate Uses a typical 2 metal-ion mechanism to dephosphorylate dATP (PubMed:33893297). Zn(2+) in the first binding site is replaced by Co(2+) in excess of the latter (PubMed:33893297). Homohexamer. Belongs to the Caudovirales dATP triphosphohydrolase family.