The tumor-promoting effect of uracil-induced calculi on rat urinary bladder carcinogenesis was investigated in male F344 rats pretreated with N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN). Since uracil-induced calculi and papillomatosis of the bladder are reversible, uracil was given for a limited period after the treatment with BBN. Animals were given 0.05% BBN in their drinking water for 4 wk a...

The uracil auxotrophic monokaryotic strain 423-9 of Lentinula edodes was crossed with nine monokaryons (cro2-2-9, W66-1, xd2-3-2, QingKe 20A, 241-1-1, 9015-1, L66-2, 241-1-2, and Qing 23A) derived from wild type strains of L. edodes. Nine dikaryotic hybrids were established from these crosses. These hybrids were fruited and 496 single spore isolates were obtained. Among these single spore isola...

The present work includes synthesis of new series heterocyclic derivatives containing 6-amino-1,3-dimethyl uracil moiety linked to 1,2,4-triazole [6-8 and 10]. first way reaction 6-amino-1,3-dimethyluracil with ethyl chloroacetate K2CO3 as catalyst in DMF solvent gives ester derivative [1]. Then, compound [1] was converted into (semicarbazide, thiosemicarbazide, phenylsemicarbazide hydrazide de...

We have identified three lesions rather than cyclobutane dimers which alter the properties of UV-irradiated poly(dC) as a template for E.coli DNA polymerase I, and have characterised these lesions with respect to their coding properties, rates of formation and decay, and their sensitivity to uracil DNA glycosylase. Our results lead us to conclude that these lesions are (1) cytosine hydrates, wh...

During spectrophotometric titrations of uracil in different alkalior alkali earth chlorides, specific changes in the U.V. absorption of uracil at PH 12.0 have been observed. The spectra of 4-methyl and 5-methyl uracil change in the same way whereas 1-methyl and 3-methyl uracil are not influenced even by strong divalent cations. From spectrophotometric and Potentiometrie titrations I I it could ...

Escherichia coli nucleoside diphosphate kinase (Ndk) catalyzes ATP-dependent synthesis of ribo- and deoxyribonucleoside triphosphates from the cognate diphosphate precursor. Recently, the Ndk polypeptide was reported to be a multifunctional base excision repair nuclease that processed uracil residues in DNA by acting sequentially as a uracil-DNA glycosylase inhibitor protein (Ugi)-sensitive ura...

Natural RNAs, especially tRNAs, are extensively modified to tailor structure and function diversities. Uracil is the most modified nucleobase among all natural nucleobases. Interestingly, >76% of uracil modifications are located on its 5-position. We have investigated the natural 5-methoxy (5-O-CH(3)) modification of uracil in the context of A-form oligonucleotide duplex. Our X-ray crystal stru...

Annulated pyrano[2,3-d]pyrimidine/pyrano[2,3-d]uracil derivatives were synthesized using aromatic aldehydes, active methylene compounds and barbituric acid in presence of dibutylamine (DBA) catalyst in ethanol as solvent. The different substituents on phenyl ring in the fused pyrano uracil skeleton showed productive influence on its antimicrobial activity against some gram positive and gram neg...