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How to choose the right plasmids for certain types of cell? - (Nov/04/2011 )

How do you know which plasmids are suitable (disregard the efficiency for now, assume you'll get enough level of expression) for say, mammalian cells? For example, this pEGFP-N1 plasmid is it suitable for HeLa cells?

Basically, I'm confused as to what "Growth strain" and "Vector type" mean.
Does Growth strain mean where the plasmid was grown and the vector type means in which type of cells (mammalian or bacterial cells) they can be transfected into?

If I'm right then, would a plasmid such as this one (for mammalian cells) grown in Ecoli be able to express its genes in bacterial cells as well?

One more thing, how can I find out the original plasmid that was used before the TP53-GFP genes were added to it?


Plasmids that are used for mammalian expression typically have a viral promoter such as CMV or SV40. Bacterial plasmids don't need this to the same extent, so they tend not to have them. However, mammalian expression constructs will often be expressed in the bacteria as well, as you might see with some GFP plasmids. It is often the case that the bacteria cannot properly fold the eukaryotic proteins, so they may not function properly if grown in bacteria.

If you want to know the parent plasmid - look for the vector backbone - which in the case you linked is pEGFP-N1 which has a GFP that will go on the C-terminus of the protein. Plasmids are often labelled such that the backbone is included in the name e.g. (made up example) pcDNA3-p53His, would be a p53 based plasmid with a His tag on a pcDNA3 backbone.