Unknown Bacteria Report

810 Words 4 Pages
The objective of this activity was to use the knowledge that we obtained throughout the semester, with the goal to correctly identify two unknown bacteria.
Organism number thirteen is Escherichia coli. On the first day, I conducted a gram stain and noticed that the bacteria were pink, meaning that the bacteria are gram negative. I also recognized that the bacteria were rod shaped therefore they were bacillus. I also noticed that the arrangement appeared to be single celled. I also put the bacteria on a streak plate. On the second day, I did another gram stain and the bacteria were again pink and bacillus or rod shaped. I also observed the bacteria on a nutrient agar plate and noticed that the bacteria were light white almost clear color bacteria. I took the bacteria that were
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On the third day, I put the bacteria that were in the broth tube on differential media. I chose to put the bacteria on EMB and Pseudo P plate, because I believed that the bacteria was either Escherichia coli or Pseudomonas aeruginosa, due to the shape and the fact that the mystery bacteria was gram negative. I also did a gram stain and the bacteria remained pink and bacillus or rod shaped. On the fourth day, I was able to observe the differential media. I noticed that on the Pseudo P plate the bacteria was a yellow color and on the EMB plate there was a small tint of metallic green color. Due to the metallic green tint on the EMB plate, the yellow pigment on the Pseudo P plate, as well as the bacillus shape, and being gram negative I concluded that the mystery bacteria number thirteen is indeed Escherichia coli. Therefore, I was able to rule out that my bacteria is not Pseudomonas aeruginosa, because on the Pseudo P plate the bacteria would have been a greenish blue color, which mine remained yellow. Also, on an EMB plate if it was

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