VARIOUS LEVELS OF ERYTHROMYCIN ON THE DEVELOPMENT OF ANTIBIOTIC RESISTANCE IN ESCHERICHIA COLI

Abstract

THIS STUDY EVALUATED MICROBIAL FITNESS UNDER SELECTIVE PRESSURE OF VARIOUS CONCENTRATIONS OF ERYTHROMYCIN AND THE DEVELOPMENT OF ERYTHROMYCIN RESISTANCE GENES IN AN ESCHERICHIA COLI (E. COLI) STRAIN. THE DEVELOPMENT OF ERYTHROMYCIN RESISTANCE GENES AND GENES EXPRESSIONS WERE EVALUATED WITH ONE CONVENTIONAL CULTURE-BASED METHOD, PLATE COUNTING METHOD, AND TWO MOLECULAR MICROBIOLOGY TECHNIQUES, FLUORESCENCE IN SITU HYBRIDIZATION ANALYSIS AND QUANTITATIVE POLYMERASE CHAIN REACTION. THE RESULTS INDICATED THAT E. COLI CELLS ADAPTED TO DIFFERENT ERYTHROMYCIN RESISTANCE LEVELS UNDER SELECTIVE PRESSURE IN THE PRESENCE OF ERYTHROMYCIN. FURTHERMORE, THE CONCENTRATION AT ONE MINIMUM INHIBITORY CONCENTRATION WAS MOST EFFECTIVE TO SELECT FOR ANTIBIOTIC RESISTANCE. THE BIOLOGICAL COSTS ASSOCIATED WITH FITNESS LED TO DIFFERENT REGROWTH RATES FOR DIFFERENT CONCENTRATIONS AND EVEN VIABLE BUT NONCULTURABLE CELLS DURING CULTIVATION. IN SUMMARY, THE ERYTHROMYCIN RESISTANT E. COLI STRAIN WELL ADAPTED TO TH