A New Modification of the Method for Assessing the Intraspecific Antagonistic Activity of Escherichia coli

Bacteriocins, such as those produced by Escherichia coli, can be considered a promising alternative to antibiotics. The method of delayed antagonism based on the cross-streak test in our modification consisting in the use of nitrocellulose membranes, provides 80% reproducibility of detection of enrofloxacin-mediated induction of E. coli colicinogeny. Both bacteriostatic and bactericidal effects of colicins from various E. coli strains were demonstrated. No differences were found between autologous and heterologous action of enrofloxacin-induced colicinogeny. E. coli isolates from pig intestines differed in the spectrum of colicin activity and complemented each other, providing cooperative antagonism. Our results highlight the potential of bacteriocins as a promising approach for combating multidrug-resistant bacteria.