Oxidized purine nucleoside triphosphate hydrolase which is a prominent sanitizer of the oxidized nucleotide pool (PubMed:8226881, PubMed:7713500, PubMed:10608900, PubMed:12857738, PubMed:22556419, PubMed:26238318, PubMed:24695224, PubMed:24695225, PubMed:28679043). Catalyzes the hydrolysis of 2-oxo-dATP (2-hydroxy-dATP) into 2-oxo-dAMP (PubMed:10373420). Has also a significant hydrolase activity toward 2-oxo-ATP, 8-oxo-dGTP and 8-oxo-dATP (PubMed:10373420, PubMed:11139615). Through the hydrolysis of oxidized purine nucleoside triphosphates, prevents their incorporation into DNA and the subsequent transversions A:T to C:G and G:C to T:A (PubMed:8226881, PubMed:10373420, PubMed:10608900, PubMed:11756418, PubMed:12857738, PubMed:16607562, PubMed:24695224, PubMed:24695225, PubMed:26999531, PubMed:28035004). Also catalyzes the hydrolysis of methylated purine nucleoside triphosphate preventing their integration into DNA (PubMed:30304478, PubMed:32144205). Through this antimutagenic activity protects cells from oxidative stress (PubMed:8226881, PubMed:7713500, PubMed:10608900, PubMed:12857738, PubMed:24695224, PubMed:24695225, PubMed:30304478, PubMed:32144205). 2-oxo-dATP + H2O = 2-oxo-dAMP + diphosphate + H(+) 2-oxo-ATP + H2O = 2-oxo-AMP + diphosphate + H(+) 8-oxo-dGTP + H2O = 8-oxo-dGMP + diphosphate + H(+) 8-oxo-dATP + H2O = 8-oxo-dAMP + diphosphate + H(+) H2O + O(6)-methyl-dGTP = diphosphate + H(+) + O(6)-methyl-dGMP H2O + N(6)-methyl-dATP = diphosphate + H(+) + N(6)-methyl-dAMP H2O + N(6)-methyl-ATP = diphosphate + H(+) + N(6)-methyl-AMP Binds 2 Mg(2+) ion per subunit. Inhibited by 2-oxo-dADP and 8-oxo-dGDP. kcat is 13.9 sec(-1) with 2-oxo-dATP as substrate (at 30 degrees Celsius and pH 8.0) (PubMed:10373420). kcat is 4.7 sec(-1) with 2-oxo-dATP as substrate (at 30 degrees Celsius and pH 7.2) (PubMed:10373420). kcat is 4.7 sec(-1) with 2-oxo-ATP as substrate (at 30 degrees Celsius and pH 8.0) (PubMed:11139615). kcat is 12.3 sec(-1) with 8-oxo-dGTP as substrate (at 30 degrees Celsius and pH 8.0) (PubMed:10373420). kcat is 2.1 sec(-1) with 8-oxo-dGTP as substrate (at 30 degrees Celsius and pH 7.2) (PubMed:10373420). kcat is 10.8 sec(-1) with 8-oxo-dATP as substrate (at 30 degrees Celsius and pH 8.0) (PubMed:10373420). kcat is 5.4 sec(-1) with O(6)-methyl-dGTP as substrate (at pH 7.5) (PubMed:32144205). kcat is 2.0 sec(-1) with N(6)-methyl-dATP as substrate (at pH 7.5) (PubMed:32144205). kcat is 8.2 sec(-1) with O(6)-methyl-dGTP as substrate (PubMed:30304478). kcat is 0.3 sec(-1) with O(6)-methyl-GTP as substrate (PubMed:30304478). Shows the best catalytic efficiency for the 2-oxo-dATP substrate (PubMed:10373420, PubMed:11139615). Shows a similar catalytic efficiency for 8-oxo-dGTP and O(6)-methyl-dGTP (PubMed:30304478). Optimum pH is 7.8-8.2 with 8-oxo-dGTP as substrate, and 8.0-8.5 with 2-oxo-dATP as substrate. Monomer. Mostly present in cytosol (PubMed:7782328). A minor proportion is mitochondrial (PubMed:7782328). A very small amount of the protein is associated with nuclei (PubMed:7782328). Widely expressed with highest expression in thymus, testis, embryo and proliferating blood lymphocytes. In peripheral blood lymphocytes, expressed at much higher levels in proliferating cells than in resting cells. The N-terminus is blocked. A polymorphism between Met-1 and Met-19 removes a stop codon before the initiation codon for isoform p22 and gives rise to the production of isoform p26. The allele frequency of isoform p26 is about 20%. Contains a predicted transit peptide (1-18) for localization to the mitochondrion. Derived from a B-type mRNA with a polymorphic alteration (GU-->GC) at the beginning of exon 2c that converts an in-frame UGA to CGA yielding another in-frame AUG further upstream. Belongs to the Nudix hydrolase family. The role in cancer cell survival is under debate. Was originally considered to play a role as a sanitizing enzyme for oxidized nucleotide pools, and thus important for the survival of cancer cells (PubMed:24695224, PubMed:24695225). A later study indicates that NUDT1 plays a redundant role in eliminating oxidized nucleotides and that it is not essential for cancer cell proliferation and survival (PubMed:28679043).