Restriction Enzymes

Restriction enzymes, also known as restriction endonucleases, are enzymes that cleave double-stranded DNA at or near specific recognition sites.

Restriction enzyme digestion is a fundamental technique in molecular biology research that enables precise manipulation and analysis/mapping of DNA. Restriction enzymes recognize specific short DNA sequences that are 4 to 8 bp in length, known as recognition sites, and introduce cuts at or near these sites. The cleavage specificity of restriction enzymes helps allow for predictable and reproducible digestion patterns, which are essential for cloning, mapping genomes, and preparing DNA for sequencing. By cutting DNA into defined fragments, researchers can isolate and study specific genes, create recombinant DNA molecules, and perform various genetic modifications. The high specificity and reliability of restriction digests make them indispensable tools in genetic engineering, functional genomics, and biotechnology. Thermo Scientific offers conventional restriction enzymes and FastDigest restriction enzymes for your molecular cloning workflows. Visit additional resources below to learn more about restriction enzymes and their specifications.

There are currently 3,000+ restriction enzymes, each with specific recognition sequences, with hundreds available commercially [1]. These enzymes are invaluable tools for preparing DNA for cloning experiments. By recognizing and cleaving specific DNA sequences, restriction enzymes generate fragments with defined ends. These fragments can be precisely manipulated and recombined to create recombinant DNA molecules.

In cloning experiments, researchers use one or more restriction enzymes to cut both the vector (a DNA molecule used to transport foreign genetic material into another cell) and the insert (the DNA fragment to be cloned) to produce compatible ends. These ends can then be joined together using DNA ligase, creating a stable recombinant DNA molecule that can be introduced into host cells for replication and expression. This precise cutting ability of restriction enzymes to cut DNA in precise locations is fundamental to the cloning process, enabling researchers to study gene function, produce proteins, and develop genetically modified organisms.

1. Restriction Enzymes. Nature Education.