restriction enzyme: meaning, definition, pronunciation and examples

Primarily, yes. They are part of the bacterial immune system against viruses (bacteriophages). Some archaea also produce them. They are not naturally found in eukaryotes like plants and animals, but are used as tools by scientists working with eukaryotic DNA.

Sticky ends (or cohesive ends) are short, single-stranded overhangs created when the enzyme cuts the two DNA strands at staggered positions. Blunt ends are created when the enzyme cuts both strands at the same base pair, leaving no overhang. Sticky ends are generally more useful for precise ligation.

The naming convention is based on the bacterial source. The first letter (capital) is the genus (E for Escherichia), the next two letters (lowercase) are the species (co for coli). The strain may follow (R for strain RY13), and the Roman numeral indicates the order of discovery from that organism (I for first).

No. Each restriction enzyme recognises and cuts only a very specific, short DNA sequence (typically 4-8 base pairs long), known as its recognition site or restriction site. If that exact sequence is not present, the enzyme will not cut the DNA.

A protein, produced by bacteria, that cuts DNA at specific nucleotide sequences.

Restriction enzyme is usually technical (biology/biochemistry/genetics) in register.

Restriction enzyme: in British English it is pronounced /rɪˈstrɪkʃən ˈɛnzaɪm/, and in American English it is pronounced /rəˈstrɪkʃən ˈɛnzaɪm/. Tap the audio buttons above to hear it.