Purification and characterization of wild-type and mutant TK1 type kinases from Caenorhabditis elegans.
Caenorhabditis elegans has a single deoxynucleoside kinase-like gene. The sequence is similar to that of human TK1, but besides accepting thymidine as a substrate, the C. elegans TK1 (CeTK1) also phosphorylates deoxyguanosine. In contrast to human TK1, the CeTK1 exclusively exists as a dimer with a molecular mass of approximately 60 kDa, even if incubated with ATP. Incubation with ATP induces a transition into a more active enzyme with a higher kcat but unchanged Km. This activation only occurs at an enzyme concentration in the incubation buffer of 0.5 micro g/ml (8.42 nM) or higher. C-terminal deletion of the enzyme results in lower catalytic efficiency and stability.
Skovgaard
T
T
Department of Life Sciences and Chemistry, Roskilde University, Roskilde, Denmark.
Munch-Petersen
B
B
D000255:Adenosine Triphosphate / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D017173:Caenorhabditis elegans; D002384:Catalysis; D019281:Dimerization; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D009154:Mutation; D011487:Protein Conformation; D017434:Protein Structure, Tertiary; D017386:Sequence Homology, Amino Acid; D013937:Thymidine Kinase / Q000235:genetics*
D000255:Adenosine Triphosphate; D013937:Thymidine Kinase; C092717:thymidine kinase 1