what is the advantages of using plasmids to incorporate foreign genes?
i dont get plasmids and why we use them. is it because they can move into bacterial cells? so does an organism with recombinant dna have genes they would normally have along with genes from the foreign dna? im so confused
2 Responses
TunaFishTaco
08 Mar 2010
Sean
08 Mar 2010
Plasmids occur naturally in many bacterial cells. They have different genes, and replicate completely seperate of their bacterial host. Scientists are reasearching methods of using these to insert new genes into bacterial, and also plant and animal cells. The genes that would be inserted by plasmids would never occur naturally in the desired cell. For example, they can insert a new gene into a bacterial cell to make it glow in the dark.
You are right about them moving into bacterial cells. Often scientists will use bacteria to express genes, either to study their function of to mass produce a protein. Genes are pretty easily inserted into plasmids ‘in vitro’ and then easily transformed into bacteria. It would be much more difficult to insert the gene into the bacterial genome, because it is much larger and more complex.
You can also insert other genes, such a anti-biotic resistance, to screen for which cells have picked up the plasmid.
Plasmids are commonly used to transform bacteria, but can also be transformed into yeast, and possibly other organisms (I’m not sure though…).