Nifurzide, a nitrofuran antiinfectious agent: interaction with Escherichia coli cells.

This paper presents a study of the interactions between Escherichia coli cells and nifurzide, a nitrofuran derivative which is used as an intestinal antiinfectious agent. At low concentrations of nifurzide, the growth rate of the cultures decreased, and elongated, nonseptate cells appeared. At high concentrations, complete growth inhibition occurred, accompanied by a rather strong bactericidal effect, but the appearance of the cells was normal; in particular, no bacteriolytic effect was observed. A very large number of antibiotic molecules were bound per bacterial cell. After cell disruption, similar amounts of nifurzide were found in the cytoplasm, cytoplasmic membranes, and cell wall, respectively. Most of the bound nifurzide was rapidly degraded or became protein bound. The structure of the outer membrane lipopolysaccharide appeared to have little influence on the activity of nifurzide.