Stabilization of SV40 transformed human fibroblast cytoplasmic thymidine kinase by ATP
- 14 Downloads
Human fibroblast cytoplasmic thymidine kinase is stabilized by ATP. Sedimentation in sucrose gradients shows that in the presence of ATP, cytoplasmic thymidine kinase has a higher molecular weight (54 000) than in the absence of ATP (28 000). Removal of ATP by dialysis results in the loss of enzyme activity. The subsequent addition of ATP restores activity following a second order time course. These results are interpreted to indicate that in a human fibroblast cell line, transformed by SV40 virus, cytoplasmic thymidine kinase is a dimer in the presence of ATP, but a less active monomer in its absence. Mitochondrial thymidine kinase from the same cell line is not affected by ATP.
KeywordsMolecular Weight Sucrose Enzyme Activity High Molecular Weight Thymidine
Unable to display preview. Download preview PDF.
- 3.Bull, D. L. et al., 1974. Virology 47: 279–284.Google Scholar
- 6.Okuda, H. et al., 1972. Cancer Res. 23: 791–794.Google Scholar
- 7.Sneider, T. W. et al., 1979. Cancer Res. 29: 40–54.Google Scholar
- 9.Taylor, A. T. et al., 1976. Cancer Res. 35: 2070–2072.Google Scholar
- 17.Chi-Cheng, Y. & Prushoff, W. H., 1974. Biochem. 13: 1179–1185.Google Scholar