You'd actually want to freeze them as fast as possible, to prevent the growth of large ice crystals that would tear the cell apart. That's why you do it by dunking them in liquid nitrogen.
But yeah frozen bacteria are basically immortal.
I mean obviously you'd use DMSO or glycerol, I just didn't want to get too technical. That being said I've always snap-frozen bacteria with LN2 and it worked just fine.
Now for eucaryotic cells, sure, you'd want to go slow.
Edit : ok now re-reading the meme I understand why you thought I was talking about eucaryotic cells. My bad !
You freeze mammalian cells by dunking them in LN2? I've... never heard of anyone do that. I've always put them in either a Mr. Frosty or a styrofoam conical holder (makeshift Mr. Frosty)
I think i imterpreted this as a bacteria that was literally living dormant in your gut from 1986 and was activated suddenly by some random food you ate.
I now understand this is a bacterium you dug out from the back of the -70 freezer and activated it
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You'd actually want to freeze them as fast as possible, to prevent the growth of large ice crystals that would tear the cell apart. That's why you do it by dunking them in liquid nitrogen. But yeah frozen bacteria are basically immortal.
No you add DMSO (5-10%) and freeze slowly. Using a Mr frosty or similar. Otherwise a few hours at -20, then -80, before the LN2.
Just chucking in LN2 is going to have terrible recovery. That might have been done with HeLa way back when but certainly isn't standard anymore.
I mean obviously you'd use DMSO or glycerol, I just didn't want to get too technical. That being said I've always snap-frozen bacteria with LN2 and it worked just fine. Now for eucaryotic cells, sure, you'd want to go slow.
Edit : ok now re-reading the meme I understand why you thought I was talking about eucaryotic cells. My bad !
You freeze mammalian cells by dunking them in LN2? I've... never heard of anyone do that. I've always put them in either a Mr. Frosty or a styrofoam conical holder (makeshift Mr. Frosty)
I really enjoy that the actual name for a scientific tool is Mr. Frosty.
I guess I forgot about the first part of the meme and was talking bacteria, sorry. For eucaryotic cells sure you'd take your time in a -80°C first.
i for one also think it's most intuitive to assume you're talking about the last part of the meme when it's not specified in the comment
whilst I approve of the use of Limmeh, I'm gonna need more context on the bacteria
from 1986?
I think i imterpreted this as a bacteria that was literally living dormant in your gut from 1986 and was activated suddenly by some random food you ate.
I now understand this is a bacterium you dug out from the back of the -70 freezer and activated it
I've used an enzyme from West Germany. Worked great.
As someone who just borked a bacterial culture that is merely three months old, I can tell not all bacteria are made equal :D