Deoxythymidine kinase

CARNOSINE SYNTHETASE CHAPERONES CHOLINE KINASE CHOLOYL-CoA SYNTHETASE COBALAMIN ADENOSYLTRANSFERASE 4-COUMAROYL-CoA SYNTHETASE CREATINE KINASE CTP SYNTHETASE CYTIDYLATE KINASE 2-DEHYDRO-3-DEOXYGLUCONOKINASE DEHYDROGLUCONOKINASE DEOXYADENOSINE KINASE DEOXYADENYLATE KINASE DEOXYCYTIDINE KINASE (DEOXYjNUCLEOSIDE MONOPHOSPHATE KINASE DEOXYTHYMIDINE KINASE DEPHOSPHO-CoA KINASE DETHIOBIOTIN SYNTHASE DIACYLGLYCEROL KINASE DIHYDROFOLATE SYNTHETASE DNA GYRASES DNA REVERSE GYRASE ETHANOLAMINE KINASE EXONUCLEASE V... 

DEOXYRIBONUCLEASES 2 -Deoxyribonucleoside diphosphate, RIBONUCLEOTIDE REDUCTASE 2-DEOXYRIBOSE-5-PHOSPHATE ALDOLASE DEOXYTHYMIDINE KINASE DEP,... 

ADENYLOSUCCINATE SYNTHETASE DEOXYTHYMIDINE KINASE FUCOSE-1-PHOSPHATE GUANYLYL-TRANSFERASE... 

AMP deoxythymidine 5 -phosphotransferase AMP deoxythymidine kinase adenylate-nucleoside phosphotransferase adenylic acid deoxythymidine 5 -phosphotransferase thymidine phosphotransferase... 

Figure 10.4 The abolition of positive cooperativity on the binding of allosteric effectors to some enzymes. Note the dramatic increases in activity at low substrate concentrations on the addition of adenosine monophosphate to isocitrate dehydrogenase, of deoxycytosine diphosphate to deoxythymidine kinase, and of fructose 1,6-diphosphate to pyruvate kinase this shows how the activity may be switched on by an allosteric effector (PEP = phosphoenolpyruvate). [From J. A. Hathaway and D. E. Atkinson, J. Biol. Chem. 238,2875 (1963) R. Okazaki and A. Kornbcrg, J. Biol. Chem. 239,275 (1964) R. Haeckel, B. Hess, W. Lauterhom, and K.-H. Wurster, Hoppe-Seyler s Z. Physiol. Chem. 349, 699 (1968).]...

Direct measurement of DNA and protein synthesis in experimental animals suggest that in zinc deficiency protein synthesis is adversely affected (, ). Our own data on human subjects in these experiments show that the total protein, total collagen, and RNA-DNA ratio Increased as a result of zinc supplementation. The activity of deoxythymidine kinase was not measurable during the zinc restriction phase but became 70% of normal level after supplementation with zinc for 3 months. Similar data have been published for experimental animals. Thus, our data show that deoxythymidine kinase in human subjects also is a zinc-dependent enzyme, and an adverse effect of zinc deficiency on this enzyme may be responsible for decreased protein synthesis. Our studies do not rule out an adverse effect of zinc deficiency on protein catabolism. Further studies are required to establish the effect of zinc restriction on protein catabolism. 

Thus changes in the zinc concentration of plasma, erythrocytes, leucocytes, and urine and changes in the activities of zinc-dependent enzymes such as alkaline phosphatase, RNase in the plasma, and deoxythymidine kinase in the tissue during the zinc restriction phase, appear to have been induced specifically by a mild deficiency of zinc in the volunteers. One unexpected finding was with respect to plasma ammonia level which appeared to increase during the zinc-restricted period. We recently have reported a similar finding in zinc deficient rats (88). This... 

These data indicate that plasma alkaline phosphatase and deoxythymidine kinase in sponge connective tissue in human subjects are zinc-dependent enzymes inasmuch as changes in their activities were related to only one dietary manipulation, namely zinc intake. Changes in the activities of plasma RNase also appear to be related to zinc intake under the conditions of our experiments. Thus the determination of the activities of these enzymes may be helpful in correlating uncomplicated zinc status in man, particularly if the changes are observed following zinc supplementation for a short period of time. 

Prasad and Oberleas (90) provided evidence that decreased activity of deoxythymidine kinase may be responsible for this early reduction in DNA synthesis. As early as six days after the animals were placed on the dietary treatment, the activity of deoxythymidine kinase was reduced in rapidly regenerating connective tissue of zinc-deficient rats, compared with pair-fed controls. These results recently have been confirmed by Dreosti and Hurley (94), The activity of deoxythymidine kinase in 12-day-old fetuses taken from females exposed to a dietary zinc deficiency during pregnancy was significantly lower than in adlibitum and restricted-fed controls. Activity of the enzyme was not restored by in vitro addition of zinc, whereas addition of copper severely aflFected the enzyme activity adversely. Recently zinc has been shown to be an essential constituent for the DNA polymerase of E. coli (95). Whether or not this enzyme is affected adversely in animal model, because of deficiency of zinc, is not known. 

Deoxythymidine kinase activity - reduced in connective tissue collagen... 

Deoxythymidine kinase, partially purified from 24 h regenerating rat liver, was markedly inhibited by BeS04 (Mainigi and Bresnick 1969). The inhibition was competitive with the cofactor, magnesium. 

Y.-C. Cheng and M. Ostrander, Deoxythymidine kinase induced in Hela TK cells by herpes simplex virus. Type I and Type II purification and characterization, J. Biol. Chem. 251 2605 (1976). 

R. Okazaki and A. Kornberg. Deoxythymidine kinase of Escherichia coli. I. Purification and some properties of the enzyme. J. Biol. Chem. 239 269, 1964. 

Bresnick, E., Williams, S. S., and Mosse, H., 1967, Rates of turnover of deoxythymidine kinase and of its template RNA in regenerating and control liver. Cancer Res. 27(Part 1) 469. 

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