Rat liver dihydrothymine dehydrogenase, the rate-limiting enzyme of thymidine and uridine degradation, was purified to homogeneity as judged by polyacrylamide disc gel electrophoresis, sedimentation velocity, and Ultrogel ACA-34 elution profile. The enzyme has a molecular weight of 220,000 +/- 5,000 as determined by Ultrogel ACA-34 and sedimentation equilibrium The s20,w value of the enzyme was...

Among various organic wastes, shrimp shell powder (SSP) was the most suitable carbon/nitrogen source for producing antinematode compounds (ANCs) via Bacillus veleznesis RB.EK7 fermentation. The fermentation process enhancement of activity investigated. B. produced highest in medium containing 0.8% SSP with an initial pH 6.5–7.0, and performed at 35–37 °C a saking speed 150 rpm 72 h. Targeting A...

ion from sugar moiety by thymine radicals in oligoand polydeoxynucleotides,

The pattern of formate-Cl4 incorporation by Ehrlich ascites tumor cells has been found to be remarkably different in vitro from the pattern of incorporation in vivo (3-5). Thus, after incubation of cells with formate-Cl4 in vitro, the specific activity of the DNA thymine was 10 to 30 times higher than that of the DNA purines. In contrast, after incorporation of formateCl4 by these cells in viva...

Electron attachment to gas phase thymine and uracil leads to H- loss within a broad and structured feature in the energy range between about 5 and 12 eV consisting of 4 overlapping resonances. By using thymine and uracil methylated at the N1 and N3 positions, respectively, and taking into account recent results from partly deuterated thymine, we find that by tuning the electron energy, H- loss ...

We have quantitated the production of thymine glycols in DNA following treatment of cultured human fibroblasts or DNA in solution with the carcinogen N-hydroxy-2-naphthylamine. Thymine glycols, detected by using a monoclonal antibody specific to this base damage, were produced in DNA in a dose dependent manner both in vitro and in vivo. Exposure of DNA to N-hydroxy-2-naphthylamine in the presen...

Thymine is reduced in dimethyl sulfoxide (E 1/2 of -2.4 V); the decrease in apparent faradaic IZ from one at infinite dilution to two-thirds at concentrations above 2 m&Z is due to proton transfer by thymine to the initially formed radical anion and the anion formed on reduction of the resulting free radical, which is more easily reduced than the parent compound. The proton transfer, which is m...

The synthesis of an oligonucleotide labeled with 13C at the thymine methyl and 15N at the exocyclic amino groups of the cytosines is described. 13CH3I and 15NH4OH were used as sources of the labels. The labeled oligonucleotide was characterized by several NMR techniques. The duplex possesses a labeled functional group in the major groove at every base pair which makes it a very suitable probe f...