Three antimicrobial nitroimidazole drugs (metronidazole, dimetridazole, and tinidazole) inhibit a range of clostridia and the protozoan Trichomonas vaginalis ; they have an identical site and mode of action as specific electron acceptors from the pyruvate phosphoroclastic reaction. Analogues of the drugs are compared and the structural requirements for activity explained. The nitrofuran (nitrof...

The trypanosomatid flavoprotein disulfide reductase, trypanothione reductase, is shown to catalyze one-electron reduction of suitably substituted naphthoquinone and nitrofuran derivatives. A number of such compounds have been chemically synthesized, and a structure-activity relationship has been established; the enzyme is most active with compounds that contain basic functional groups in side-c...

Binding of several nitroheterocycles by mammalian cells is a function of the ambient oxygen concentration; anoxic single cells bind up to 10 times as much of these drugs as do aerobic cells. We thus hypothesized that fluorescent nitroheterocyles could be used to quantitate the fraction of hypoxic cells in multicell systems, and this was tested in multicell spheroids using a relatively nontoxic ...

The paper describes the prevalence of resistant strains within the genetic structure of E. coli (phylogenetic group A, B1, B2 and D). A total of 200 commensal E. coli strains have been derived from 10 species of healthy animals residing on ZOO Safari Park area, in Swierkocin, Poland. The phylogenetic structure of E. coli has been analysed with the use of a PCR-based method. The strains were tes...

Wild-type Escherichia coli cells are sensitive to nitrofurazone (NF) and many other nitrofuran derivatives. A variety of evidence indicated that these compounds are converted to toxic "active" metabolites by reductases present in the bacteria. Sensitive E. coli K-12 acquired threefold-greater resistance to NF in one mutational step. These partially resistant mutants could undergo a second mutat...