Microbiology Unknown Project - 2014
Instructions.
General. For the next several weeks, your sole responsibility will be to identify the two microbes in the test tubes you have been handed. You will find Bergey's Manual of Determinative Microbiology to be a very helpful resource. The 7th Edition can be found online at:
http://openlibrary.org/books/OL23280747M/Bergey%27s_manual_of_determinative_bacteriology.
Please note that some of the names in that version are now quite outdated. For example, C. freundii is called Escherichia fruendii in the manual and Kosuria rosea is Micrococcus rosea. If you have questions, please ask.
I also have the 9th edition of the manual in my office, and it can be purchased or rented online for those of you who really want your own copy.
Final Unknowns Report. You must use the Unknown Excel Template to develop a separate report for each of your unknown bacteria. The template can be found linked to the online class syllabus. These Excel Documents must also be linked to your electronic portfolio under the laboratory skills section. The reports consist of four sections:
Part 1: Required Tests – A complete morphological description of your unknown cells and your unknown colonies.
Part 2: Additional Tests – Name each additional test that you perform, write down the names of the positive and negative control species that you used (if the negative control is just a blank tube, write ‘blank’), and provide a succinct result (Red = Gram Negative). Do NOT explain how the test works, elaborate on your results or otherwise attempt to edify me. Please give the briefest answer possible.
Part 3: Complete Laboratory Notebook - In addition to filling out all of the required information in the Excel Document, you must keep a complete laboratory notebook documenting all of the work that you do on your unknown. Each page (from now on) should be dated and titled. You should describe what tests you did, and describe/interpret any results you observed. I will be collecting the lab notebooks at the end of the semester.
Due Date: Your microbial identifications and Final Unknowns Reports are due no later than May 3 at 5:00 pm via email.
Final Lab Cleanup April 23. You must come to lab on April 23 for a final lab walkthrough/cleanup. No one will receive a final grade in Microbiology Lab until the entire lab area is clean (beer refrigerator, lab counters, incubators, etc). IF you skip the final clean up, you will receive a zero for the unknown project.
Clean-up Rules.
1. Daily.
- You are each responsible for keeping 232 and the prep room clean at all times during this project. You must wash all of the glassware that you use to make media as you use it. Do not leave it in the prep room or the lab for someone else to wash.
- Make sure to put all media/reagents back on the correct shelves, and to clean up the weighing station every time you finish making media.
- Do not let your Petri plates linger in the incubator for more than 2-3 days. I have a nasty habit of throwing ‘rogue’ plates away.
- Old Petri plates should be placed in the biohazard bag in 232. Old test tubes should be placed in the “Kill Racks” in 232. Please separate tubes with agar from tubes with just broth.
- Each student may store up to two slant cultures and three Petri plate cultures of each of their unknowns in the beer refrigerator at any one time. Older cultures should be properly disposed of in the biohazard bag (for plates), or in the “Kill Rack” in 232 for test tubes. No other cultures/plates may be stored in that (or any other!) refrigerator.
- Test tubes/Petri plates containing experimental results must be disposed of immediately as described in (d).
2. Weekly.
Once a week (starting this week) one team will be in charge of making sure that the media area in 232 is in good order, that 232 is as neat as possible, and that all tubes in the ‘Kill Racks’ are autoclaved, emptied, cleaned and put away. There will be a sign-up calendar in 232. Each team should sign up for one clean up slot.
Frequently-Asked Questions (and my answers):
1. Q: Is this a positive? (Or any other version of is this right, did this work, etc…)
A: Did you run a positive control (a bacterium that is known to be positive for the reaction you are doing) and a negative control (media with no bacteria in it, but otherwise treated just like the experimental media/culture)? If you did, you should be able to answer the question for yourself. Control bacteria are present in the ‘control’ racks in the 232 refrigerator.
2. Q: How do I make_____?
A: First, look in the back of your lab manual, or in the text of the lab experiment that you are doing. The recipe is almost always there. Also, don’t forget to check the microbiology media area for premixed powders. We often have them for the most popular tests (for example, we have phenol red broth base…just add sugar). If your media/reagent formulations are not in either place, then feel free to ask. Just remember that it will take us a while (at least a week) to get particularly strange media – so plan ahead to make sure you have what you need.
3. Q: What if I name the wrong bacterium at the end of all this?
A: Don't panic. You will get points for the percent of tests that you did correctly. In other words, it is possible (though less likely) to name the wrong bacterium, and still get an A.
4. Oh, please! Give us a Hint!
Well, ok then. Your bacteria can be found in the list below. Unknowns may be repeated, so don’t panic if someone else seems to have the same unknown that you do.
Alcaligenes faecalis
Bacillus cereus
Bacillus megaterium
Bacillus subtilis
Caulobacter vibroides
Chromobacterium violaceum
Citrobacter freundii
Corynebacterium xerosis
Enterobacter aerogenes
Enterococcus faecalis (Streptococcus faecalis)
Escherichia coli
Haemophilus parainfluenzae
Klebsiella pneumoniae
Kosuria rosea (Micrococcus roseus)
Lactobacillus acidophilus
Lactococcus lactis
Micrococcus luteus
Moraxella (Branhamella) catarrhalis
Morganella morganii
Mycobacterium smegmatis
Neisseria subflava
Proteus vulgaris
Providencia stuartii
Pseudomonas aeruginosa
Psuedomonas syringae
Salmonella enteritidis
Salmonella paratyphi
Serratia marcescens
Shigella flexneri
Sporosarcina ureae
Staphylococcus aureus
Staphylococcus epidermidis
Streptococcus salivarius