Saturday, October 13, 2012: 9:40 PM
Hall 4E/F (WSCC)
The use of various staining procedures allows biologists to observe microbes more clearly. The BacLight fluorescent stain was used to test the effectiveness of three different antibiotics against E.coli and S. aureus. The antibiotics were expected to be more effective on gram positive bacteria than on gram negative bacteria[hmc1] . First, we verified the Gram reaction of the bacteria we were dealing with using the Gram stain process. Then bacteria were exposed to tetracyline, kanamycin or ampicillin over a 3 hour period to test how well each antibiotic worked on both types of bacteria. An aliquot of culture was removed and stained with the BacLight fluorescent stain at several time points.. Cells were observed with epifluorescent illumination, images were collected and live/dead cell counts were made. Consistent with the hypothesis, the gram negative bacteria, E. coli, was much less effected by the antibiotics . S. aureus was more susceptible to death from these three antibiotics. The data also shows that kanamycin was the most effective of the three antibiotics tested. The experiment demonstrated the effectiveness of three different antibiotics against E.coli and S.aureus.
[hmc1]For what reason?