Researchers use many techniques to discover new antibiotics. Biologists collect unique bacterial samples from soil and try to isolate antibiotic compounds targeting some of the most harmful infectious bacteria using Tiny Earth's protocol. One crucial step is when researchers take an antibiotic producing bacteria that they've isolated and grow it up over an entire petri dish to collect a large amount of it.
To complete this procedure, Tiny Earth scientists need quadrant streak plates for each of the bacterial samples they're isolating, a new LB agar plate for each sample they wish to isolate, and sterile cotton swabs.
Each dish is labelled with the scientist's three initials (if they don't have a middle name, they just use the first two letters of their first name and then the first letter of their last name), the date of use, and the ID of the bacteria isolate. Researchers use sterile cotton swabs to pick an isolated colony from each of their quadrant streak plates, and then spread that colony over the entirety of a new petri dish.
In the lab, they usually use the smaller petri dishes for these maintenance lawns, as an entire regularly sized petri dish would be much more than they need. To give the maintenance lawn time to grow, they leave them in a 26°C incubator for 1-2 days.
When the scientists check their plates after incubation, they should look like the one shown above!
Maintenance lawns are needed because you need bacteria that is identical for the procedures going forward (Gram staining, ESKAPE testing, etc.). Having an entire lawn of bacteria descended from the same exact colony is tremendously useful.
Matt
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