The pathways for the formation of DNA-thymine from syn thesis de novo and from exogenous thymidine (TdR) have been studied in intact leukocytes from patients with chronic myelogenous leukemia. The most significant observations were as follows: (a) DNA-thymine derived from exogenous TdR in creases from 13% to 87% over a range of TdR concentrations from 0.03 /¿Mto 300 /XM.(b) TdR causes expansio...

Dihydropyrimidine dehydrogenase deficiency is an inborn error of pyrimidine metabolism characterised by thymine-uraciluria, convulsive disorders and developmental delay in paediatric patients, and an increased risk of toxicity from 5-fluorouracil treatment. This report is of the first patient with dihydropyrimidine dehydrogenase deficiency diagnosed in Hong Kong. The patient was a 2-day-old mal...

The effect of thymine-5-bromouracil substitution on the regeneration and length of F pili produced by an F(+)Lac(+)/Lac(-)Thy(-) strain of Escherichia coli was studied by electron microscopy. When 5-bromouracil (5BU) incorporation into deoxyribonucleic acid (DNA) was maximal, the modal length of the pilus doubled and the number of pili per cell was approximately 50% that of thymine-grown cells....

Bodmer, Walter F. (Stanford University School of Medicine, Palo Alto, Calif.), and Susan Grether. Uptake and incorporation of thymine, thymidine, uracil, uridine, and 5-fluorouracil into the nucleic acids of Bacillus subtilis. J. Bacteriol. 89:1011-1014. 1965.-From 55 to 95% of uracil, uridine, or 5-fluorouracil (FU) added to the culture medium is incorporated into the acid-insoluble fraction o...

Oxidation of a DNA thymine to 5-hydroxymethyluracil is one of several recently discovered epigenetic modifications. Here, we report the results of nanopore translocation experiments and molecular dynamics simulations that provide insight into the impact of this modification on the structure and dynamics of DNA. When transported through ultrathin solid-state nanopores, short DNA fragments contai...

From replacement studies (1) and inhibition analysis (2) with microorganisms requiring folic acid, it has been inferred that this vitamin is concerned in the biosynthesis of purines and of thymine. More directly, folic acid has been shown to be involved in nucleic acid synthesis in Lactobacillus casei (3,4). According to Buchanan and Schulman (5), the formation of purine derivatives would seem ...

Multiphoton ionization of thymine and uracil clusters generated by a supersonic molecular beam gave rise to a remarkable alternation of mass spectral intensities between even- and odd-numbered clusters. Such alternation was observed in clusters of up to 30 molecules. Excitation to the two lowest electronically excited states seemed to be a strong prerequisite. In view of the well known photodim...

We report the preparation of a deoxyribooligonucleotide containing a new thymine (6-4) photoproduct analog. The (6-4) photoproduct is one of the major forms of DNA lesions, and leads to mutation in DNA. An antibody (64M5) that binds the (6-4) photoproduct has been described. To investigate the interaction of the photoproduct with the 64M5 antibody, we prepared a (6-4) photoproduct analog in whi...

An activity has been purified 350-fold from extracts of mouse plasmacytoma cells that forms 5-hydroxymethyluracil (alpha-hydroxythymine) and apyrimidinic sites with phage SPO1 DNA, which contains this base in place of thymine. This DNA glycosylase presumably functions to eliminate hydroxymethyluracil, a major thymine-derived DNA lesion produced by ionizing radiation and oxidative damage. The en...

Luzzati, Denise (Institut de Biologie Physico-Chimique, Paris, France). Effect of thymine starvation on messenger ribonucleic acid synthesis in Escherichia coli. J. Bacteriol. 92:1435-1446. 1966.-During the course of thymine starvation, the rate of synthesis of messenger ribonucleic acid (mRNA, the rapidly labeled fraction of the RNA which decays in the presence of dinitrophenol or which hybrid...