Frequency evaluation of genes encoding siderophores and the effects of different concentrations of Fe ions on growth rate of uropathogenic <i>Escherichia coli</i>.

Abstract

BACKGROUND AND OBJECTIVES: (UPEC) isolates. We also analyzed the effects of siderophore genes beside iron supplements on growth rate of the isolates. MATERIALS AND METHODS: strains were isolated from urinary tract infections and the presence of 3 siderophore genes were analyzed using PCR among them. Three final concentrations of 0.1, 0.5 and 1 mMFe(II) and Fe(III) ions were made in M9 broth medium. Inoculated cultures were incubated at 37°C for 33 hours and bacterial density in the suspension was measured with 1 hour intervals using spectrophotometer. RESULTS: <0.0001). Differences between Fe(III) supplemented groups and the controls were statistically significant when 1 mM concentration was added into the medium (p<0.05). CONCLUSION: gene probably plays a major role in the pathogenesis of UPEC strains. Promoting or inhibitory effects of iron on bacterial growth mainly depend on the iron concentration in the culture medium however different siderophores have different potentials for capturing and assimilation of Fe ions by the bacteria, especially inside the host cell.