Plays an essential role in generating the deoxyribonucleotide precursors dGTP for DNA metabolism. Highly specific toward deoxyguanosine (dGuo) and deoxyinosine (dIno). Only marginal activity is observed with guanosine. UTP is slightly more efficient as phosphate donor than CTP, ATP and GTP. 2'-deoxyguanosine + ATP = ADP + dGMP + H(+) Inhibited by deoxyguanosine at concentrations above 30 uM only with UTP as phosphate donor. dGTP is a potent competitive inhibitor. Optimum pH is around pH 9 (with saturating concentrations of dGuo and UTP). At pH 7.5 and 11.5 more than 80% of maximal activity is still observed. At pH 6.0, 60% activity remains, whereas the enzyme is completely inactive below pH 5.6. Homodimer. Catalysis proceeds by a classical ping-pong bi-bi reaction mechanism. Belongs to the DCK/DGK family.