Phosphorylates the deoxyribonucleosides deoxycytidine, deoxyguanosine and deoxyadenosine (PubMed:27906638). Displays highest activity against deoxycytidine followed by deoxyadenosine and then deoxyguanosine (PubMed:27906638). Shows only very minor activity against deoxyuridine and deoxythymidine (PubMed:27906638). 2'-deoxycytidine + a ribonucleoside 5'-triphosphate = a ribonucleoside 5'-diphosphate + dCMP + H(+) 2'-deoxyadenosine + ATP = ADP + dAMP + H(+) 2'-deoxyguanosine + ATP = ADP + dGMP + H(+) kcat is 0.05 sec(-1) with deoxycytodine as substrate. kcat is 4.07 sec(-1) with deoxyadenosine as substrate. kcat is 1.23 sec(-1) with deoxyguanosine as substrate. kcat is 1.05 sec(-1) with deoxyuridine as substrate. kcat is 1.08 sec(-1) with deoxythymidine as substrate. Homodimer. Expressed at high levels in adult intestine, spleen, thymus and testis with lower levels in skeletal muscle and eye. In the embryo, expressed at higher levels until day 10 with lower levels in later stages. Belongs to the DCK/DGK family.