How is the pGLO plasmid introduced into the E. coli cell?
The general process by which foreign DNA is introduced into a cell is called transformation. There are several ways to transform DNA into an E. coli cell, but the most common way is by making the cells competent. “Competent” cells have the ability to take up DNA molecules from the environment Normal E. coli are not competent, however, if they are treated with a solution of calcium chloride their cell membranes become competent Actually, only a small fraction of the cells treated with CaCl2 are able to take up foreign DNA, however, since the number of cells in a sample is large, the low efficiency of transformation is not much of a problem. The selectable markers ensure that only the cells that did take up the foreign DNA (i.e. plasmid) will survive and grow. Expression of GFP Addition of arabinose sugar to the growth media will cause RNA polymerase to start transcribing the GFP gene (i.e. making mRNA molecules). The cellular machinery (e.g. ribosomes) will translate this mRNA into corr
