Introduction
Enterococci are bacteria that are included in the intestinal flora of humans and are relatively harmless. One method Enterococci maintain a symbiotic relationship is by hydrolyzing esculin in the presence of bile (Susan L. Fraser, 2012). However Enterococci are in the top three-nosocomial infections. When infected, enterococci can cause numerous infections such as urinary tract infection coupled with fever (Susan L. Fraser, 2012). More specifically, Enterococcus Faecalis causes urinary tract infections. Enterococcus Faecalis (E. Faecalis) is a gram-positive bacteria that is difficult to eliminate. With an increasing dependency on antibiotics, E. Faecalis is becoming feared due to its intrinsic antibiotic resistance (Wesley Glick, 2000). This strain is naturally immune to weaker levels of penicillin because of its ability to synthesize cell wall components in the presence of penicillin. Instead of allowing this antibiotic to destroy the cell wall, E. Faecalis produces penicillin-binding proteins that inhibit penicillin from disintegrating its cell wall (Susan L. Fraser, 2012). Thus a more effective antibiotic must be used. For the purposes of this study, Penicillin, Tetracycline, and Ampicillin have been chosen to counter E. Faecalis. Based on a previous study completed by Wesley Glick, E. Faecalis is intrinsically resistant to weak Penicillin and Tetracycline (Wesley Glick, 2000). Therefore a hypothesis can be generated stating that Penicillin and Tetracycline will be partially ineffective towards eliminating E. Faecalis. However, since the Penicillin and Tetracycline used in this experiment are more potent, it is predicted that all three antibiotics will be effective against E. Faecalis, with Ampicillin exhibiting the largest zone of inhibition.
Materials
Enterococcus Faecalis was taken from a stock sample and was spread across a blood agar plate.
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