Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.1.21 (thymidine kinase)
 7,561 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The influence of phenestrol and XTJI-51 (hexestrol alkylating derivatives) on uterine tissues and their ability to bind to estrogen receptors were studied. The both compounds studied exhibited estrogenic properties and imitated all effects of estradiol: they increased the uterine wet weight and the activity of thymidine kinase and glucose-6-phosphate dehydrogenase. Although their affinity for estrogen receptors was much weaker than the affinity of estradiol, their complexes with estrogen receptors were more stable than estrogen-receptor complexes.
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PMID:[Properties of alkylating derivatives of estrogens]. 651 Mar 35

By means of metaphase chromosomes, the genes for mink thymidine kinase (TK) and hypoxanthine-phosphoribosyltransferase (HPRT) were transferred to mutant mouse cells, LMTK-, A9 (HPRT-) and teratocarcinoma cells, PCC4-aza 1 (HPRT-). Eighteen colonies were isolated from LMTK- (series A), 9 from A9 (series B) and none from PCC4-aza 1. The transformed clones contained mink TK or HPRT. Analysis of syntenic markers in series B demonstrated that one clone contained mink glucose-6-phosphate dehydrogenase (G6PD) and the other alpha-galactosidase; in series A, nine clones contained mink galactokinase (GALK) and six mink aldolase C (ALDC). Analysis of 12 asyntenic markers located in ten mink chromosomes showed the presence of only aconitase-1 (ACON1) (the marker of mink chromosome 12) in three clones of series A. The clones lost mink ACON1 between the fifth to tenth passages. Cytogenetic analysis established the presence of a fragment of mink chromosome 8 in eight clones of series A, but not in series B. The clones of series A lost mink TK together with mink GALK and ALDC during back-selection; in B, back-selection retained mink G6PD. No stable TK+ phenotype was detected in clones with a visible fragment of mink chromosome 8. Stability analysis demonstrated that about half of the clones of series B have stable HPRT+ phenotype whereas only three clones of series A have stable TK+ phenotype. It is suggested that the recipient cells, LMTK- and A9, differ in their competence for genetic transformation and integration of foreign genes.
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PMID:Cotransfer and phenotypic stabilisation of syntenic and asyntenic mink genes into mouse cells by chromosome-mediated gene transfer. 659 20

The effects of ovariectomy and estrogen treatment on the activity of thymidine kinase in estrogen-dependent and estrogen-independent mammary gland tumors (MGT) of experimental animals were studied. Thymidine kinase activity decreased 3-18 fold after ovariectomy in estrogen-dependent MGT only. It increased 3-7 fold again after estradiol treatment. These changes were significantly greater than those in hexokinase and glucose-6-phosphate dehydrogenase activity. High doses of estrogens (200 micrograms/day) resulted in an 1.8-3.5-fold decrease in thymidine kinase in estrogen-dependent MGT. The enzyme activity in estrogen-independent MGT did not change. It is suggested to use thymidine kinase activity as a marker of proliferative processes in evaluation of hormone-dependency of tumors and the effects of other factors on tumor growth.
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PMID:[Thymidine kinase activity in mammary tumors of animals exposed to estradiol as an index of tumor hormone dependence]. 714 34

Cytoplasmic fractions from species of the Mollicutes genera Entomoplasma, Mesoplasma, Mycoplasma, and Acholeplasma were assayed for NADH oxidase (NADH ox), ATP- and PPi-dependent phosphofructokinase (PFK), ATP- and PPi-dependent deoxyguanosine kinase (dGUOK), thymidine kinase (TK), TMP kinase (TMPK), glucose-6-phosphate dehydrogenase (G6Pde), lactate dehydrogenase (LDH), malate dehydrogenase (MDH), phosphoenolpyruvate carboxylase, hypoxanthine-guanine phosphoribosyl transferase, dUTPase, and uracil-DNA glycosylase (UNG) activities. Membrane fractions were also examined for NADH ox activity. These activities were used as indicators of the presence and relative activities of major Mollicutes metabolic and DNA repair pathways. This was the first study to determine the presence of these enzymes in members of the genera Entomoplasma and Mesoplasma. Using the data obtained, we constructed a preliminary scheme for distinguishing genera of the class Mollicutes on the basis of the results of signature functional enzyme assays. This scheme includes phylogenetic relationships deduced from rRNA analyses, but is more informative with respect to metabolic potential. The criteria used include the presence of PPi-dependent PFK, urease, dUTPase, and dGUOK activities. Entomoplasma ellychniae ELCN-1T (T = type strain), Entomoplasma melaleucae M-1T, Mesoplasma seiffertii F7T, Mesoplasma entomophilum TACT, Mesoplasma florum L1T, Mycoplasma fermentans PG18T, and Acholeplasma multilocale PN525T were similar in most respects. NADH ox activity was localized in the cytoplasm of these organisms. These strains had ATP-dependent PFK, MDH, LDH, ATP- and PPi-dependent dGUOK, and UNG activities, but not dUTPase or G6Pde activities. In contrast, Acholeplasma equifetale C112T, Acholeplasma oculi 19LT, Acholeplasma hippikon C1T, Acholeplasma modicum PG49T, and Acholeplasma morum 72-043T had membrane-localized NADH ox activity, PPi-dependent PFK, G6Pde, and dUTPase activities, and significantly lower MDH and LDH activities and exhibited a faster rate with PPi than with ATP in the dGUOK reaction. All of the members of the Mollicutes tested had hypoxanthine-guanine phosphoribosyl transferase, phosphoenolpyruvate carboxylase, and (except for Mesoplasma entomophilum TAC(T)) UNG activities. All of the Acholeplasma strains except Acholeplasma multilocale PN525T had TK, TMPK, and UNG activities. Mesoplasma entomophilum TAC(T) was distinguished by having no detectable dUTPase, UNG, TK, and TMPK activities, indicating that there is a severe restriction in or an absence of a synthetic route to dTTP. Our data also suggest that A. multilocale PN525T is a member of an unrecognized metabolic subgroup of the genus Acholeplasma or is not an Acholeplasma strain.
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PMID:Comparative metabolism of Mesoplasma, Entomoplasma, Mycoplasma, and Acholeplasma. 886 14


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