Interesting.
I have a question, why not pair Gene A with something still detectable but less "dangerous", like a gene that change body color, or emit different color under UV light.
Sorry i am totally noob here
I have a question, why not pair Gene A with something still detectable but less "dangerous", like a gene that change body color, or emit different color under UV light.
Sorry i am totally noob here
There's also the fact that bacteria tend to lose non-adaptive traits pretty quickly once the selection pressure is gone, so having the antibiotic resistance attached to your gene of interest makes it much more likely to stick around for the duration.
Additionally, as others have said, this particular antibiotic (from the post) isn't even used for human treatment so it's not really particularly more "dangerous", we just tend to get nervous around anything "antibiotic resistant" because we jump to thinking about like, MRSA.
And you want clones, so all identical bacteria derived from a single successful integration of your plasmid into a bacterium. You don't want a mixture of bacteria with different DNA. This process isn't perfect and you need to screen out cases where your DNA sequence is not correct. And by far the easiest way to do that is to grow on plates with antibiotics, and an amount of bacteria that results in a few individual colonies, with each clone being full of genetically identical bacteria.
You generally want antibiotics in your media anyway, working without antibiotics makes it much more difficult. You don't have 100% perfectly sterile conditions, with antibiotics you have a much larger margin here.
Worse case it could be 10^11 cells for a strain of bacteria that doesn’t transform well.
You would have to look at a lot of colonies to find the one that transformed.