1. Attack of the Superbugs Lab Introduction Mrs. Stewart Medical Interventions

2. Superbugs What is a “superbug”? – Bacteria that have become stronger and less responsive to antibiotic treatment

3. How can bacteria share resistance? Genetic Transfer Method Description ConjugationThe one-way transfer of DNA (plasmid) between bacteria in close cellular contact TransformationThe genetic modification of a bacterium by incorporation of free DNA from the surrounding environment (usually caused by another ruptured bacterial cell) TransductionThe transfer of genetic material from one bacterium to another by a genetic vector (bacteriophage virus)

4. This lab uses 2 types of Bacteria: E. coli I – contains a gene found on the chromosomal DNA coding for streptomycin resistance E. coli II – contains a gene found on the plasmid DNA coding for ampicillin resistance.

5. Predict What will happen when the E. coli I strain is mixed with the E. coli II strain?

6. Lab Materials: 4 growth plates LB Agar LB + Amp LB + Str LB /Str /Amp *LB Agar = growth medium for bacterial cells

7. Lab Day 1: Confirmation Plates Obtain 1 of each type of growth plate – 4 plates total Streak E. coli I on 4 plates Streak E. coli II on 4 plates Incubate overnight

8. How to label the plates I II Group Name

9. Evaluate What are we confirming? These plates will confirm that our strains of E. coli are correctly labeled

10. Data Table E. coli IE. coli II LB agar LB + Str LB + Amp LB + Str + Amp + = Growth/ -- = No Growth

11. Prediction Predict the results from your confirmation plates that you will expect to record

12. Lab Day 2: Observe confirmation plate results Prepare “mix” plate – You will literally be mixing the two types of bacteria together onto one plate Incubate overnight

13. Evaluate Specifically, what will happen when we mix them together?

14. Lab Day 3: Use new “mixed” bacterial cultures and spread onto the 3 types of antibiotic plates

15. Predict What would you expect to see on these growth plates? Why?

16. Lab Day 4 Observe and record your results Remember: Pictures of lab results will be required in your lab reports *Growth plates will be discarded after today. Any results not recorded will be lost.

17. Student Lab Schedule Day:Time Needed: Activity:How to Store: Lab Day 1 ~ 30 minutes Students prepare confirmation plates. Invert the plates, label, and incubate at 37˚C for 24 hours. Lab Day 2 ~ 30 minutes Students observe confirmation plates and prepare “Mix Plate.” Invert the plates, label, and incubate at 37˚C for 24 hours. Lab Day 3 ~ 30 minutes Students streak cultures from “Mix Plate” onto antibiotic plates. Invert the plates, label, and incubate at 37˚C for 24 hours. Lab Day 4 ~ 10 minutes Students observe & record results Clean-up all materials.