dGTPase preferentially hydrolyzes dGTP over the other canonical NTPs. dGTP + H2O = 2'-deoxyguanosine + H(+) + triphosphate Inhibited by the action of reducing agents such as dithiothreitol and 2-mercaptoethanol. Optimum pH is 8.2. Thermostable. Fully active at 60 degrees Celsius. Homotetramer. Belongs to the dGTPase family. Type 1 subfamily.