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Plasmid coli glycerol stocks @ -20 - will they still be useable? (Jan/08/2008 )

Hi,
last week (off course during my vacation) the -80 broke down. The people of my lab removed the stuff from this freezer and put most of it in a -20 room. My e. coli glycerol stocks (coli's with a plasmid inserted) were also put at -20. They are standing there now for one week. Can I still use them? I don't think they have died, do they? Or do you think they have all lost there plasmid? (but that can be sscreened easily by plating them on selective plates). Or could anything else has happened?

-aspergillie-

QUOTE (aspergillie @ Jan 8 2008, 11:12 AM)
Hi,
last week (off course during my vacation) the -80 broke down. The people of my lab removed the stuff from this freezer and put most of it in a -20 room. My e. coli glycerol stocks (coli's with a plasmid inserted) were also put at -20. They are standing there now for one week. Can I still use them? I don't think they have died, do they? Or do you think they have all lost there plasmid? (but that can be sscreened easily by plating them on selective plates). Or could anything else has happened?


Why don't you grow up a few and test them?

-Clare-

streak it on a plate. Thats the best way to know.

-scolix-

QUOTE (scolix @ Jan 8 2008, 03:39 PM)
streak it on a plate. Thats the best way to know.

I did that indeed.
It was just that someone else wanted to grow up this coli today and if you guys had said "it's not going to work" , then we would have done the plasmid tranformation again to save time.
Tomorrow we will see. Thanks!

-aspergillie-

I know some people who keep some glycerol stocks at -20ºC. They don't last for so long but are ok for some time.

-Ambrósio-