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electroporation with DH5a vs XL10-Gold - any difference for large plasmids? (Aug/02/2011 )

I am trying to generate a mutant library for a 7.4kb plasmid from ligation. I've been working with DH5a and recently got hold of some XL10-Gold, which supposedly gives better transformation efficiency for large plasmids and ligation products.

1) XL10-Gold is sold as a chemical competent cell for large plasmids and ligation products. Can I prepare electrocompetent cells from the stock? Would it perform as well as the chemical competent ones? Just curious why it's not sold in the electrocompetent form as well.

2) If I prepare electrocompetent DH5a and XL10-Gold with the same transformation efficiency using pUC18, would XL10 transform better for larger plasmids?

Thanks!

-donny-

You can certainly prepare electrocompetent cells from that stock. In general the transformation efficiency for electroporation is higher than most chemical transformation. I don't know how that would work for large constructs (but I don't think of 7.5Kb as especially large).

-phage434-