Micro Unknown

Gram stain and KOH string test are definitely the first ones you should do. My class had a minimum of 10 tests we had to do, but I did 15 just in case I had conflicting results. Give each organism points for each test result they don't match up with, and your organism will have the least number of points (ideally zero). Don't be afraid to redo tests if you can.

Oh this is so me right now! We are doing our micro unknown right now. The first thing you need to do is gram stain because that eliminates a lot of possibilities. And if your gram stain is gram negative rods then you could eliminate the endosperm stain and get straight on acid fast, capsule, and your motility sim test!

First, you need to make a dichotomous key. Once you have an initial plan you can start testing. Some people use the gram stain to start, but if you make a mistake in procedure it can set you back. We started with culturing on TSA, MSA and EMB plates. MSA to isolate the gram + and EMB to isolate your gram - and the TSA to make sure you had two distinct bacteria in your vial. Follow your key, do extra tests and you should have your unknown in a few weeks!

I'm not sure how any other school/professor does the unknown, but when I took micro we performed each test for our unknowns along with the labs performed that week. So one of of the first labs was gram staining, once we were comfortable with that we did our unknowns. We started with the gram stain and morphology. So we did have a little guidance on where to begin and what testing to do.

Some of it did suck because even if you weren't comfortable with a technique you still had to perform the unknown testing and do follow up results the next week.

From what I'm understand are you not given any guidance from the professor on where he/she wants yall to do things?

Anyways, good luck! Doing the unknown project in micro was my favorite thing in any science course I had taken.

I forgot all of the steps that I took but yes, gram stain should be the first thing that you do

This is very difficult for people who are color blind. I had isolated my organism in the second week, but, didn't realize it because it looked like I had pink AND purple on my gram stain. I asked classmates near the final week to look and they said all they saw was purple. I was like FMLLLLLL.

Loved micro though, lol.