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transformation of a big plasmid in E. coli - something wrong is happening in my transformation (Dec/29/2005 )

Hi, everybody!

First of all, sorry my english...

I need to transform (by heat shock transformation) a big clone (14kb - where the plasmid is pBR322 and my insert has 9kb). By miniprep, I see that something enters in bacteria, but a big part of my insert is being deleted. By a digestion, I see that my vector is intact, however only 2kb of my insert is intact.

Could the bacteria (Stable) delete part of my insert????
And what can I do about it?????

Thank you so much for your attention.

-Nathalia-

So you mean your insert is 9kb and vetor ~5kb!! huh.gif Anyway try using recombinase minus strains such as XL1Blue or Stbl2 to avoid recombination after tran formation.

-Molonco-

my boyfriend has corrected me...
it is "sorry ABOUT my english"

sorry, sorry and sorry again and ABOUT other mistakes!!!!

-Nathalia-

What are those other mistakes which your boyfriend corrected?

-Molonco-

He said only about that mistake...

The others are possible mistakes!!!

I don´t write in english for many years... If I could write in portuguese... smile.gif

And thanks for your suggestion!!

-Nathalia-

And I forgot to say that I use STBL to transform...
So, I don´t know what can be...

-Nathalia-

As i can make it out..since the plasmid is too big probably the cells are throwing out/losing the plasmid.But even then holding only 2kb and throwing out the rest is not reasonable/logical.I would suggest you increase the antibiotic conc. that you're using to grow the cells...i guess it must be Amp...so try increasing the Amp conc to say 200 microg/microl

-izeman-