Tools for Genetic Engineering

Whatever the eventual goal - a working diagnostic, a transgenic crop, a recombinant vaccine - actually generating a recombinant DNA molecule always comes down to the same three categories of basic tool. First, enzymes: specifically the restriction enzymes that cut DNA at defined points, DNA ligase that seals cut ends back together, and alkaline phosphatase that prevents unwanted self-sealing. Second, vectors: the self-replicating carrier molecules, most often plasmids, that actually transport the DNA fragment into a host. Third, a competent host organism willing and able to take up and propagate that vector. The next several sections work through each of these tool …