Alexis Grettenberger 800503431
Katie Young
Alexis Grettenberger
Biol 311 Lab
11/21/14
Preliminary Unknown Report
Purpose:
The purpose of this experiment was to identify a specific unknown bacterium that was isolated from a multitude of bacteria in a sample of contaminated dirt by running it through a series of identification techniques. Some of these techniques were simple staining, gram staining, and isolation techniques. The hypothesis of this experiment was that the bacterium is of the bacillus family due to the rod shape. Due to multiple complications with the PCR, a new hypothesis couldn’t be formulated.
Methods: In this experiment, a 1 gram sample of contaminated dirt was taken and mixed with 100 mL of sterile water then shaken. After allowing the sediment to settle to the bottom, a sample of the water was taken. With the sample, a sterile loop was used to inoculate a TSA petri plate by doing a quadrant streak, which is aseptically done by making an initial streak, then sterilizing and repeating by streaking out of one portion of the previous streak no more than the initial streak. This was done a maximum of four times, insuring that the bacteria culture is "thinned" out enough to take a sample from an individual colony. This was repeated one other time and both were refrigerated at 37 degrees for a minimum of 24 hours. Each plate was labeled with names, the date, the class section, and “unknown” (Leboffe, M., & Pierce, B. (2012)).
After retrieving the plates from the fridge, a sample was aseptically taken off an individual colony, from either TSA plate, with a loop and inoculated on a TSA slant. As before label the slant accordingly. The slant was refrigerated as well for 24 hours at 37 degrees. After retrieving the slant, inoculate a broth tube with a loop full of bacteria then allow the bacteria to grow in the broth (Leboffe, M., & Pierce, B. (2012)).
Staining is the next step in identifying the unknown bacteria.
Cited: Leboffe, Michael J., and Burton E. Pierce. "Microscopy and Staining." Brief Microbiology Laboratory Theory & Application. 2nd ed. Englewood, CO: Morton, 2012. 159-178. Print. Leboffe, M., & Pierce, B. (2012). Microscopy and Staining. In Brief Microbiology Laboratory Theory & Application (2nd ed.). Englewood, CO: Morton Publishing.