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Plate storage & picking colonies - How much time do I have? (May/22/2006 )

I'm sure this question must have been asked in the past but after much searching I haven't been able to find an answer (found a heap of other great advice though!).

I'm new to cloning and in my enthusiasm performed way too many ligations and transformations. Consequently I have a heap of plates sitting in the fridge with lots of white colonies waiting to be picked (approx 400-450 bp inserts in pGEM T Easy vector).

My question is roughly how long can these plates be kept at 4C and does longer storage in any way effect the quality/success of sequencing? Are there any other issues I need to be wary of?
I will either miniprep cultures or templiphi the plasmid (probably the latter). Any comments would be greatly appreciated smile.gif . Thx.


I usually pick the colonies within a week after having them in 4C but I have picked colonies even after 2 weeks and they still have worked out fine. It shouldnt matter for sequencing as well.


scoolix is right. Picking colonies 1-2weeks at most is ok. The tough point for sequencing is the plasmid prep itself in fact. clean and good DNA is the parameter.


I did minis of month old (or more) plates and recovered my plasmid
Drawback: fridge looks like a jungle


Thanks for the quick replies - much appreciated!