Hi, I want to perform a plasmid stability test for a recombinant bacteria and hence have to passage the bacteria (for 30 generations).
For each generation, I will count the cfu on the antibiotic selective agar plate and compare with normal agar plate.
My question is, how do I passage bacteria in this case?
1. Pick a single colony from previous passage, grow in 5ml broth overnight, and take 100 ul to plate the bacteria.
2. Pick a single colony from previous passage, resuspend in 100 ul broth and plate the bacteria.
Which is better?
Normally how do you do it?