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Plasmid DNA isolation - neutralisation of DNA (Jul/09/2009 )

I have one doubt if anyone can please suggest me. During plasmid prep. by alkali lysis method, if its possible to do this with 3M Sodium acetate rather than 3M potassium acetate as both have the same role in precipitating the DNA. How can both cations influence the DNA precipitation in yield and quality.

Any suggestions would be welcomed

Thanks

-preeti_RNA-

Short answer, no. Potassium dodecyl sulfate precipitates, while sodium dodecyl sulfate (SDS) is soluble. The precipitation of the SDS is a key part of bringing the genomic DNA out of solution, allowing the plasmid DNA to remain free, and then transferred to the column after spinning down the cell debris, KDS, genomic DNA

-phage434-

phage434 on Jul 9 2009, 02:44 PM said:

Short answer, no. Potassium dodecyl sulfate precipitates, while sodium dodecyl sulfate (SDS) is soluble. The precipitation of the SDS is a key part of bringing the genomic DNA out of solution, allowing the plasmid DNA to remain free, and then transferred to the column after spinning down the cell debris, KDS, genomic DNA


Thanks for the reply. But last time when i used 3M sodium acetate for miniprep, i still got the plasmid DNA which was Ok and even sequencing result is fine. Though i never tried doing downstream proceesing like restriction digestion and transcription.

I feel more discussion on this will be helpful.

Thanks :)

-preeti_RNA-

Why did you ask "is it possible" if you'd already done it?

-HomeBrew-

HomeBrew on Jul 9 2009, 03:37 PM said:

Why did you ask "is it possible" if you'd already done it?


When i made the post, that time i did not have my sequencing results with me , before using the solution for next time i was doubtful about the use of 2 cations and i feel its better to discuss doubts in this forum...and then felt sharing the experience as well.

cheers

-preeti_RNA-

OK -- I just noticed your first two posts were just a few hours apart, and thought I'd ask...

-HomeBrew-