pyrophosphate and azauracil

We measured the concentration of nucleoside triphosphates and inorganic pyrophosphate in Escherichia coli in conditions where nucleotide synthesis or nucleic acid synthesis was inhibited. The inhibitors that brought about an accumulation of some of the four ribonucleoside triphosphates also increased the pyrophosphate level. In a pyrimidine auxotrophic strain uracil starvation led to simultaneous accumulation of ATP and pyrophosphate, and they both rapidly returned to normal level when starvation was relieved. These results indicate the possible involvement of pyrophosphate in the reactions leading to the accumulation of nucleoside triphosphates.

Topics: Adenosine Triphosphate; Chromatography, High Pressure Liquid; Diphosphates; Escherichia coli; Fluorouracil; Hydroxyurea; Luminescent Measurements; Mercaptopurine; Mutation; Ribonucleotides; Species Specificity; Uracil

Partial inhibition of DNA synthesis stimulates the production of inorganic diphosphatase in Escherichia coli but the changes in diphosphate (PPi) level observed did not correlate with the enzyme activity. An accumulation of PPi was observed in the presence of inhibitors of RNA synthesis or nucleotide synthesis. In the former case the level of the enzyme did not change but in the latter case it increased. Thus the amount of inorganic diphosphatase alone does not determine the concentration of PPi in E. coli.

Topics: Diphosphates; DNA Replication; Escherichia coli; Fluorouracil; Inorganic Pyrophosphatase; Kinetics; Mutation; Nalidixic Acid; Pyrophosphatases; Transcription, Genetic; Uracil

Topics: Adenine; Adenosine Triphosphate; Antimetabolites; Bacillus subtilis; Colorimetry; Diphosphates; Escherichia coli; Mutation; NAD; NADP; Niacin; Nicotinic Acids; Nucleotides; Nucleotidyltransferases; Pharmacology; Research; Spectrophotometry; Uracil