Investigating Enterococcus faecalis’s structures and resistances to antibiotics
Introduction
(Abranches et al., 2013).
Bacteria’s phenotype is commonly described as gram-negative or gram-positive from conducting a gram stain. A bacterium that is gram-negative tends to have cells composed of a thin peptidoglycan layer, and a gram stain of gram-negative bacteria is seen as red or pink through a microscope (Smith and Hussey, 2005). On the other hand, a bacterium that is gram-positive will have cells made of a thick peptidoglycan layer, and the gram stain of a gram negative bacteria would be seen blue or purple (Smith and Hussey, 2005). In particular, Enterococcus faecalis is a gram-positive bacterium which has been found in many infections …show more content…
We measured the zone of inhibition after a week to observe which antibiotic Enterococcus faecalis is most sensitive to. My hypothesis is that Enterococcus faecalis will have varying levels of sensitivity to different types of antibiotics by expressing different size of zone of inhibition. If neomycin, tetracycline, and erythromycin are individually applied to a colony of Enterococcus faecalis, then the zone of inhibition will be highest to lowest in the order of neomycin, erythromycin, and tetracycline. I based this order based on my research that suggest tetracycline would be least effective because Enterococcus faecalis has found to be resistant to tetracycline in 58% of the isolates. Whereas, erythromycin should be slightly more effective than tetracycline because the study indicated that only 38% of isolates were resistance as compare to 58% for tetracycline. Neomycin was rank to be the most effective because a break out of high-level gentamicin resistant Enterococcus faecalis was noted to be not resistant to neomycin in a Norwegian hospital(Wendelbo et al., 2003). Furthermore, we also made a gram stain of bacterium Enterococcus faecalis and viewed it through microscope to determine if it is gram-positive or gram-negative. Overall, our goal of the experiment was to investigate Enterococcus faecalis’s characteristics …show more content…
First, the back of the agar plate was labeled with the person’s name, bacteria that was tested, and the various antibiotics. This can seen in figure 1 where the the agar plate had lines drew with a marker on it to divide the four different treatments: control, neomycin, erythromycin, and tetracycline. Sterile swab was used to wipe
Antibiotic dispensers with antibiotic disks of neomycin, erythromycin, and tetracycline was attained from the instructor.
Introduction
(Abranches et al., 2013).
Bacteria’s phenotype is commonly described as gram-negative or gram-positive from conducting a gram stain. A bacterium that is gram-negative tends to have cells composed of a thin peptidoglycan layer, and a gram stain of gram-negative bacteria is seen as red or pink through a microscope (Smith and Hussey, 2005). On the other hand, a bacterium that is gram-positive will have cells made of a thick peptidoglycan layer, and the gram stain of a gram negative bacteria would be seen blue or purple (Smith and Hussey, 2005). In particular, Enterococcus faecalis is a gram-positive bacterium which has been found in many infections …show more content…
We measured the zone of inhibition after a week to observe which antibiotic Enterococcus faecalis is most sensitive to. My hypothesis is that Enterococcus faecalis will have varying levels of sensitivity to different types of antibiotics by expressing different size of zone of inhibition. If neomycin, tetracycline, and erythromycin are individually applied to a colony of Enterococcus faecalis, then the zone of inhibition will be highest to lowest in the order of neomycin, erythromycin, and tetracycline. I based this order based on my research that suggest tetracycline would be least effective because Enterococcus faecalis has found to be resistant to tetracycline in 58% of the isolates. Whereas, erythromycin should be slightly more effective than tetracycline because the study indicated that only 38% of isolates were resistance as compare to 58% for tetracycline. Neomycin was rank to be the most effective because a break out of high-level gentamicin resistant Enterococcus faecalis was noted to be not resistant to neomycin in a Norwegian hospital(Wendelbo et al., 2003). Furthermore, we also made a gram stain of bacterium Enterococcus faecalis and viewed it through microscope to determine if it is gram-positive or gram-negative. Overall, our goal of the experiment was to investigate Enterococcus faecalis’s characteristics …show more content…
First, the back of the agar plate was labeled with the person’s name, bacteria that was tested, and the various antibiotics. This can seen in figure 1 where the the agar plate had lines drew with a marker on it to divide the four different treatments: control, neomycin, erythromycin, and tetracycline. Sterile swab was used to wipe
Antibiotic dispensers with antibiotic disks of neomycin, erythromycin, and tetracycline was attained from the instructor.