UMP-CMP kinase 2, mitochondrial (CMPK2)

Function

• may participate in dUTP & dCTP synthesis in mitochondria
• is able to phosphorylate dUMP, dCMP, CMP, UMP & monophosphates of the pyrimidine nucleoside analogs ddC, dFdC, araC, BVDU & FdUrd with ATP as phosphate donor
• efficacy is highest for dUMP followed by dCMP; CMP & UMP are poor substrates
• may be involved in mtDNA depletion caused by long term treatment with ddC or other pyrimidine analogs

ATP + dCMP <--> ADP + dCDP

Kinetic parameters:

• KM=3.09 mM for CMP
• KM=6.3 mM for UMP
• KM=1.31 mM for dCMP
• KM=0.1 mM for dUMP
• Vmax=1.64 umol/min/mg enzyme towards CMP
• Vmax=0.19 umol/min/mg enzyme towards UMP
• Vmax=1.77 umol/min/mg enzyme towards dCMP
• Vmax=0.48 umol/min/mg enzyme towards dUMP

Structure

belongs to the thymidylate kinase family

Compartment

mitochondria

Alternative splicing

named isoforms=4

Expression

• among all investigated tumors, leukemia cells show the most abundant expression

More general terms

• enzyme
• mitochondrial protein

Database

• UniProt: http://www.uniprot.org/uniprot/Q5EBM0.html