Parker the Pathologist
Hi Richard!
That sounds like a fun experiment. I think the easiest way to get E coli would be to swab stool and streak it on MacConkey Agar. E coli will grow as pink colonies. A few other types of bacteria will also grow pink, like Salmonella, Shigella and Yersina. To prove it is E coli, you could pick a pink colony from the MaConkey agar and swab it on Levine EMB agar, where it will grow out as black colonies with a greenish sheen. If you already ordered a nonselective media and don't want anything more complex, you could still do the experiment without knowing exactly which species you are working with. Just streak a single colony from the first plate onto a second one to get a single type of bacteria. The bacteria should be grown at room temperature away from direct light. The main thing is to not get bacteria outside of the Petri dish, wash really well, and not get sick. The Petri dishes will generally stay fresh for about a month if stored in the fridge, but I would never put them in the fridge after growing anything on them.
I love you, Richard. Thanks for telling me about your cool experiment. Let me know how it goes.
Love,
Joseph

