This enzyme decreases the intracellular concentration of dUTP so that uracil cannot be incorporated into viral progeny DNA. This activity is sufficient to exclude uracil from the DNA during phage replication. In the case of dUTPase mutant phages, the host dUTPase activity is not sufficient to exclude uracil from T5 DNA and uracil are incorporated, leading to decreased phage viability. dUTP + H2O = diphosphate + dUMP + H(+) Pyrimidine metabolism; dUMP biosynthesis; dUMP from dCTP (dUTP route): step 2/2. Expressed in the early phase of the viral replicative cycle. Belongs to the dUTPase family.