Low yield plasmid extraction - (Aug/23/2007 )

Hi all,

I am working on pBI121. It is a low copy plasmid and my extraction is too faint. I used midiprep.
Could anyone say me how I can improve it?

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Hi...
just a few question:
-are you using a kit?From which source?
-in how many ml you grow the bact?
Probably the first thing is to increase the volume of the bacterial grow..so you will get more plasmid...

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Hi Fulvioce

I handle 10 ml E. coli culture. In fact I can't increases my bacterial culture too much because the risk of extracted plasmid with contaminations will increase .

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And I don't use any kit

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Try using chloranfenicol in addition of the antibiotic of selection, it work for my low copy plasmid preps.
Increase you volume culture.

Start the incubation without chloranf, after 3 hours, add the chloranf and incubate overnight.

Hope this help

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Agree with that..Aztecan Princess..you have always the best tricks GoodLuck!!

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For low copy plasmids, we grow a starter culture (10ml) during the day and then use it to inoculate the overnight culture. Either a midi or a maxi prep kit gives a good yield.

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