What are restriction enzymes?
Restriction enzymes are proteins isolated from bacteria that cleave a DNA sequence at a specific location to form a DNA fragment of a known sequence at each end. The use of restriction enzymes is required for some laboratory techniques, including recombinant DNA technology and genetic engineering.
Traditionally, the four types of restriction enzymes, designated I, II, III, and IV, are known to differ primarily in structure, cleavage site, specificity, and cofactors.
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