Bacterial Resistence to Ampicillin

In this experiment we chose to grow ampicillin resistant strains of E. coli on plates of increasing concentrations of ampicillin. By doing this, we hoped to increase the resistance of the E. coli to higher concentrations of ampicillin. We set up three trial groups. Two groups were subjected to increasing concentrations and one group remained at a steady concentration of ampicillin. We plated liquid cultures of E. coli bacteria on agar plates with designated concentrations of ampicillin, and let them grow over night. After 24 hours, we transferred a portion of these bacteria onto new agar plates with higher concentrations of ampicillin. After 10 days, we increased the ampicillin concentrations in all the trails, bringing them up to 750 mg/ml from either 50 mg/ml or 450 mg/ml. We observed the results. The trials that grew on increasing concentrations grew at the 750 mg/ml. The trial that grew on constant concentrations also grew at the 750 mg/ml, which should not have happened according to previous research. We later determined that the results were inconclusive because the ampicillin used in the experiment was bad and had no effect on the bacteria.

Research Done By:

Jackie Allar

Anne Gamble