Studies on Multiple Antibiotic Resistance Gene in Aeromonas

Three xylanase-producing Aeromonas strains (St1, So1 and So2) were isolated from stagnant water from Rajshahi University campus. The strains were isolated on xylan agar media and screened by -xylanolysis method. This strains showed drug resistance to cotrimoxazole, ampicilline and amoxycilline when tested by disc diffusion method on nutrient agar or xylan agar plate respectively. This strains also showed sensitive to erythromycin, tetracycline and doxycyclin. The minimum inhibitory concentration (MIC) of erythromycin, tetracycline and doxycyclin was determined by serial dilution technique against three test bacterial strains. The MIC values of the above three drugs against St1 were 250, 125 and 250 μg ml-1, against So1 and So2 were 125, 62.5 and 125 μg ml-1 respectively. Plasmid DNA was isolated the multi-drug resistant strain St1. These drug resistant plasmids were transformed into sensitive E. coli LE 392. The transformed LE392 became resistant to cotrimoxazole, ampicilline and amoxycilline and the respective plasmid DNA was detected in the plasmid DNA isolated from transformed E. coli cells. The antibiotic resistant in Aeromonas was plasmid born.