Phosphorylation of 9-beta-D-arabinofuranosylguanine monophosphate by Drosophila melanogaster guanylate kinase.
Nucleoside monophosphate kinases have an important role in the synthesis of nucleotides that are required for cellular metabolism. These enzymes are also important for the phosphorylation of nucleoside- and nucleotide analogs used in cancer and anti-viral therapy. We report the cDNA cloning and characterization of a 23 kDa guanylate kinase from Drosophila melanogaster (Dm-GUK). The predicted amino acid sequence was 58% identical to the human guanylate kinase and the enzyme was shown to phosphorylate GMP and dGMP with ATP as phosphate donor. The monophosphates of the deoxyguanosine analogs 2',2'-difluorodeoxyguanosine (dFdG) and 9-beta-D-arabinofuranosylguanine (araG) were also shown to be phosphorylated by the enzyme. We used the enzyme to reconstitute the complete in vitro three-step phosphorylation pathway for the conversion of dGuo and araG to the corresponding triphosphates.
Johansson
Magnus
M
Karolinska Institute, Department of Laboratory Medicine, Novum, S-141 57 Stockholm, Sweden.
Amiri
Marjan
M
Karlsson
Anna
A
D000595:Amino Acid Sequence; D000818:Animals; D001088:Arabinonucleotides / Q000378:metabolism*; D001483:Base Sequence; D003001:Cloning, Molecular; D017931:DNA Primers; D018076:DNA, Complementary; D004331:Drosophila melanogaster / Q000201:enzymology*; D051528:Guanylate Kinases; D008969:Molecular Sequence Data; D009703:Nucleoside-Phosphate Kinase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity
C505040:9-beta-D-arabinofuranosylguanine monophosphate; D001088:Arabinonucleotides; D017931:DNA Primers; D018076:DNA, Complementary; D009703:Nucleoside-Phosphate Kinase; D051528:Guanylate Kinases