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Background and objectives: Bacterial resistance rates to antibiotics and decontaminants are constantly rising. Bacteriocins represent a possible alternative, as these bacterial proteins lyse strains of the same and closely related species. Until now, mainly bacteriocins from Escherichia (E.) coli strains isolated from human samples have been described. To develop a bacteriocin based decontaminant against pathogenic E. coli in food, bacteriocin producer strains were isolated from food and environmental samples. These bacteriocins will now be further characterized and compared to the bacteriocins already described. Materials and methods: In a spot assay overnight cultures and bacteriocin extracts of 136 E. coli strains isolated from food and environmental samples were examined for their lysis profile on eight indicator strains.
Results: A bactericidal effect could be observed in 85 (63 %) of the overnight cultures and 51 % of the bacteriocin extracts. After cocultivation of the bacteriocin producing isolates with the E. coli strain DH5α some were able to lyse a broader range of indicator strains.
Conclusion: Percentage of bacteriocin producing E. coli strains from food and environmental samples coincides with the percentage rates found in E. coli extracted from human samples. The bacteriocins will now be further characterised and their lytic activity tested against pathogenic E. coli strains.