EC Microbiology

Antibiotic resistance plasmid pCG86 was isolated from the pathogen ETEC present in the stool of dead piglet apparently responsible for the death of piglet after suffering from diarrhoeal disease. This ETEC carried plasmid pCG86 of 117Kb containing genes for the production of enterotoxin both heat stable and heat labile but the use of antibiotics at a low dose can’t be effective because the piglet lacking body immunity but on the contrary produced transposons. What made me think there was an abuse of antibiotics because the piglets were lacking body immunity apparently essential for the efficacy of antibiotics. Dr. Carlton Gyles, (Professor of Veterinary College, Waterloo University, Canada) failed to save these piglets. An article was published in American Journal (Science) in the year 1977. It was collaborative project between Dr. Gyles (Canada) and Dr. Palchudhuri & Prof. Maas (USA). They showed this pathogen ETEC carries a single plasmid pCG86 carrying genes for the production of enterotoxin both heat stable and heat labile as well as antibiotic resistance transposons. Evidently antibiotics failed to save these piglets. Before this work Dr. Gyles sent the same E. coli ETEC isolate to his Ph.D. mentor Professor S. Falkow (University of California) with clinical history. Subsequently Dr. Falkow transferred pCG86 by mating with E. coli K-12 (711) and saved in a nutrient agar stab.Therefore, Professor Maas wanted me to characterize. After characterization we concluded that the antibiotic resistance plasmid pCG86 becomes Ent p307 but lost only antibiotic resistance characters (transposons) but not the toxin genes when transferred into E. coli K-12 (711).

Keywords: Antibiotic Resistance Transposons; Bacterial Pathogens Growth; Antibiotics Free Environment

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