Cytidine Monophosphate Kinase 1 (CMPK1)

Uridine monophosphate (UMP)/cytidine monophosphate (CMP) kinase (EC 2.7.4.4) catalyzes the phosphoryl transfer from ATP to UMP, CMP, and deoxy-CMP (dCMP), resulting in the formation of ADP and the corresponding nucleoside diphosphate. These nucleoside diphosphates are required for cellular nucleic acid synthesis.

The longest deduced protein contains 228 amino acids and has a calculated molecular mass of 26 kD. However, translation likely begins at the second initiation methionine, resulting in a protein of 196 amino acids. UMP/CMP kinase has a glycine-rich nucleoside triphosphate-binding region followed by a nucleoside monophosphate-binding site in its N-terminal half and a lid domain in its C-terminal half.