The human adenylate kinase 9 is a nucleoside mono- and diphosphate kinase.

Article Details


Amiri M, Conserva F, Panayiotou C, Karlsson A, Solaroli N

The human adenylate kinase 9 is a nucleoside mono- and diphosphate kinase.

Int J Biochem Cell Biol. 2013 May;45(5):925-31. doi: 10.1016/j.biocel.2013.02.004. Epub 2013 Feb 14.

PubMed ID
23416111 [ View in PubMed

Adenylate kinases regulate adenine nucleotide levels and are present in different intracellular compartments. These enzymes also participate in the activation of pharmacologically active nucleoside and nucleotide analogs. We have in the present study identified the ninth isoform of the adenylate kinase family of enzymes and accordingly named the protein adenylate kinase 9 (AK9). Initially a full-length cDNA of a hypothetical protein containing a predicted adenylate kinase domain was identified and subsequently cloned and expressed in Escherichia coli. The substrate specificity of the recombinant protein showed that the enzyme catalyzed the phosphorylation of AMP, dAMP, CMP and dCMP with ATP as phosphate donor, while only AMP and CMP were phosphorylated when GTP was the phosphate donor. The kinetic parameters of AK9 were determined for AMP, dAMP and CMP with ATP as phosphate donor. Interestingly, in addition to the diphosphate products, a nucleoside diphosphate kinase (NDPK) activity was also present with subsequent triphosphates formed. With ATP or GTP as phosphate donor it was possible to detect the production of ATP, CTP, GTP, UTP, dATP, dCTP, dGTP and TTP as enzymatic products from the corresponding diphosphate substrates. A number of previously characterized adenylate kinases were also tested and found to possess a broad phosphotransferase activity similar to AK9. These enzymes are accordingly suggested to be regarded as nucleoside mono- and diphosphate kinases with catalytic activities possibly determined by local substrate concentrations.

DrugBank Data that Cites this Article

NameUniProt ID
UMP-CMP kinaseP30085Details
Adenylate kinase isoenzyme 1P00568Details
Adenylate kinase 8Q96MA6Details
Adenylate kinase 4, mitochondrialP27144Details