Using Sticky Ends to Construct Recombinant DNA

If samples of DNA from two different sources are digested with the same restriction enzyme and then mixed, in some cases the sticky ends that anneal to 

The other principal vector is a plasmid—bacterial DNA that is not part of the main circular DNA chromosome of the bacterium. This DNA, which usually 

While the theory of cloning DNA into a plasmid is straightforward, there are several considerations for a successful experiment. When bacteria take up a plasmid, we say they have been transformed. Transformation is the process whereby new DNA is incorporated into a host. Bacteria are encouraged to take up foreign DNA by a couple of methods. One is to heat-shock the bacteria at 42°G, followed by placing them on ice. Another is to place them in an electric field, a technique called electroporation. 

How are we to know which of the bacteria have taken up the plasmid Because bacteria divide quickly, we would not want all the bacteria to grow—rather, only the ones that have the plasmid. This process is called selection. Each plasmid chosen for cloning must have some type of selectable marker that lets us know that the growing bacterial colonies contain the plasmid. These markers are usually genes that confer resistance to antibiotics. After transformation, the 

The acronym pUC stands for wniversal doning /iasmid. Each of these cloning vectors has an extensive MCS, which helps solve another problem with 

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