Experiments have been carried out with Neurospora which demonstrate that the quantitatively important route for the biosynthesis of the pyrimidine deoxyribonucleosides in the DNA* of this organism involves the entire carbon skeleton of a pyrimidine ribonucleoside. A very high labeling of the pyrimidine nucleosides of the RNA and DNA was brought about by feeding uniformly labeled CY4-cytidine to...

UV inactivation, photoreactivation, and dark repair of Escherichia coli and Cryptosporidium parvum were investigated with the endonuclease sensitive site (ESS) assay, which can determine UV-induced pyrimidine dimers in the genomic DNA of microorganisms. In a 99.9% inactivation of E. coli, high correlation was observed between the dose of UV irradiation and the number of pyrimidine dimers induce...

The findin«that 7r,8f-dihydroxy-9,10f-oxy-7,8,9,10-tetrahydrobenzo(a)pyrene (BPDE-I) is stabilized against hydrolysis by binding to cellular membranes suggested that nucleophilic compounds which would colocalize with BPDE-I in membranes might inhibit the deleterious biological effects of BPDE-I. We have explored the possibility that hydrophobic, sulfhydryl-containing compounds might provide su...

The finding that 7r,8t-dihydroxy-9,10-t-oxy-7,8,9,10-tetrahydrobenzo(a)pyrene (BPDE-I) is stabilized against hydrolysis by binding to cellular membranes suggested that nucleophilic compounds which would colocalize with BPDE-I in membranes might inhibit the deleterious biological effects of BPDE-I. We have explored the possibility that hydrophobic, sulfhydryl-containing compounds might provide s...

The electrochemical corrosion prevention of engines and mechanisms is a task great national, economic defense importance. Lubricating oils commonly used in engineering do not have sufficient protective properties are unable to effectively protect it from corrosion, both during operation short-term long-term inactivity. One the simplest most rational ways solve this problem use lubricants contai...

(Hetero)aroyl chlorides, alkynes, and ethyl 2-mercapto acetate can be reacted in a consecutive three-component synthesis to give 2,4-disubstituted thiophene 5-carboxylates in good to excellent yields. In the sense of a pseudo-five-component reaction highly blue luminescent symmetrical terthiophenes and a quinquethiophene can be synthesized in excellent yield.

Here we report the effect of passivating diluent chain length and sensor interrogation temperature on the electrochemical DNA (E-DNA) sensor's mismatch discrimination capability. Both stem-loop and linear probe-based E-DNA sensors were constructed with various diluents, including 6-mercapto-1-hexanol and longer chain hydroxyl-terminated alkanethiols. Contrary to previously reported results, we ...

Intracellular Toxoplasma gondii grown in human foreskin fibroblast cells transported nitrobenzylthioinosine [NBMPR; 6-[(4-nitrobenzyl)mercapto]-9-beta-D-ribofuranosylpurine], an inhibitor of nucleoside transport in mammalian cells, as well as the nonphysiological beta-L-enantiomers of purine nucleosides, beta-L-adenosine, beta-L-deoxyadenosine, and beta-L-guanosine. The beta-L-pyrimidine nucleo...

We compared the removal of pyrimidine(6-4)pyrimidone photoproducts [(6-4) photoproducts] and cyclobutane pyrimidine dimers (CPDs) from the genome of repair-proficient Escherichia coli, using monoclonal antibodies specific for each type of lesion. We found that (6-4) photoproducts were removed at a higher rate than CPDs in the first 30 min following a moderate UV dose (40 J/m2). The difference i...