BIOL 3110 Lecture Notes - Transferase, Restriction Enzyme, Ethidium Bromide
Document Summary
This process of creating a restriction map is based on the idea that there are different recognition sites for the various other types of endonucleases. Some of the restriction enzymes will leave sticky or staggered ends that allow for the creation of recombinant dna molecules (the staggered ends of each piece allows for modified reannealing). There are three types of restriction enzymes (i, ii, iii) but only type ii is used for mapping. Type i does not create dna fragments reproducibly; type iii can cut reproducibly but has a cognate methylase associated with type i and forms a complex when in the same solution. The staggered ends are palindromic and allow for the reannealing of the ends, the conditions for reannealing are different from those of digestion. Differ in length and sequence of recognition sites; the shorter recognition sites (i. e. 4bp vs. 6bp) will appear more frequently than those of the longer ones.
