I am running into some frustrations with my unknown. This is a summer class, so we only have this week to work on the unknown. The only info we are given is 16 possibilities (which we had to track down the test results for over the semester) and the tests we must run to gain some of our points (if they give the correct result).
I did my gram stain yesterday and at first I thought I lucked out because it automatically narrowed it to three possibilities. Gram positive cocci in pairs or short chains and the only three that meet that description are E. faecalis, S. salivarius and L. lactis. So then I started double checking all of my info on those specific microbes so I could be ready to identify during our next (and last) lab and I'm finding that every single test we are using has the same result for those three. We are NOT using any tests that would actually ID between those three. We are doing motility, catalase, glucose (and gas), lactose (and gas), TSI, citrate, MacConkey's, thioglycollate, indole, gelatinase and then she will give us the oxidase test results since we don't have the test materials. No blood agar, no mannitol salt agar, no other hydrolysis tests that would indicate between Streptococcus, Lactococcus and Enterococcus.
I am feeling frustrated and like I must be missing something. I've worked really hard to fill out the charts with these test results. I rented Bergey's (what she recommended using), so I could use that at home (two kids = no library time), I've searched all over online trying to use reputable sources and I still cannot find anything! So my thought is 1. I'm missing something and am going to totally screw up my unknown and that makes me mad because I've worked so hard, 2. maybe I should redo my gram stain Wednesday IF I have time just to double check OR 3. MAYBE the answer is that we cannot ID between those three because all of the tests we are using are better for gram- rod ID, specifically Enterobacteriaceae - something that has shown up time and time again as we've practiced the tests throughout the semester.
Any help?? What should I do? We can use any source imaginable at this point (including discussing with others and classmates) outside of asking the professor at this point.
We can use any source imaginable at this point (including discussing with others and classmates) outside of asking the professor at this point.