What is the main function of a restriction enzyme?

The main function of a restriction enzyme is to cut DNA at specific restriction sites. These enzymes are produced naturally by bacteria as a defense mechanism against invading viruses or foreign DNA. When a restriction enzyme encounters a specific sequence of nucleotides, it recognizes and binds to that sequence, subsequently catalyzing a cleavage of the DNA strand at or near that precise location. This property of restriction enzymes enables them to be powerful tools in molecular biology, widely utilized in recombinant DNA technology, cloning, and the analysis of genetic material.

The specificity of restriction enzymes is crucial as it allows for targeted manipulation of DNA, facilitating tasks such as gene cloning and the creation of genetic constructs. This pinpoint accuracy distinguishes restriction enzymes from other molecular tools that do not perform similar cut-and-paste functions on DNA.