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bacteria storage - (Oct/12/2005 )

Is there any way to store bacteria that doesn't involve making an overnight broth culture first? To make a glycerol stock do you need the overnight culture? Or can you just take colonies from an agar plate?



you want good log phase cells in suspension

if you want to do it in one day, inoculate a small amount of broth early in the morning (assuming e coli or something that grows fast) and make glycerol stocks in the afternoon

if you use colonies, many of those cells are in stationary phase and it is harder to get good recovery from the freezer.


Aimikins is right, the best is to prepare from a fresh culture, but if you are really in a hurry and find no colleague to do it for you, you can always resuspend a colony in 15% glycerol (adding salt like 0.8% NaCl or 4g/l Na Metaphosphate help too) and freeze that.

Another solution is to prepare conservation medium. You just pick your colony deep into the tube and you can keep your tubes in the dark at room temperaturen for years. But I admit that even if I had succes ressucisitating some culture from the 70's stored this way, I never prepared any, and wouldn't know (or even want) to do that.



I think mel4n6 is referring to what we used to call stab cultures. There are also slants. Any fairly good intro to micro book will show you how to make them (it's essentailly solid media in a cryo tube), and they do work well.


it is always better to preserve the fresh grown culture. But it is not always that we need a liquid (broth) culture. you can take colonies from a plate better if these are not very old. then suspend these colonies in a glycerol stock (10% ) and can be preserved for long time.