Week 12:
Exercise 19: Indentification of Enteric Pathogens
Identification of Bacterial Unknown
- Exercise 15 Report Due
- Each student will get a single unknown to identify, using a flow chart (you can make one to give them,
based on results of our organisms) based on the media listed below.
- There should be at least three complete sets of all 6 or 7 known organims on the all the media the students will
be using for them to observe results for in class.
- I hope we can figure out a flow chart without needing to use the tryptic nitrate broth, gelatin hydrolysis, or the oxidase test.
- If you haven't graded gram stains and streak plates yet, this would be a good week for it.
Lab Orders for Week 12
- Demonstration Media for Known Organisms--one set for each of the known organisms, to be inoculated on Sunday before labs, with extras for I, MR, and VP
- Media (one set per person):
- 1 TSA plate, 1 TSI slant, 1 SIM deep, 2 OF-glucose tubes, 1 MR broth, 1 VP broth,
1 citrate slant, 1 Hektoen plate, 1 MacConkey's plate, 1 urea slant, 1 tube mineral oil (at least 4 ml)
- Equipment:
- scopes, Gram stain reagents, loops, needles
- Reagents:
- VP A, VP B, Kovac's, methyl red
- Cultures:
- One numbered unknown per student, preferably on a slant, of one of the following organisms
- Known organisms on media: E. coli, E. aerogenes, P. mirabilis, Sal. arizona or typhimurium, Ps. aeruginosa, Serr. marcescens
- (We may include Shigella, but not hand it out to students.)
- Gram positive organism (B subtilis?)--a few per lab if we need to grade mixed Gram stains this week.