restriction enzyme

noun

, Biochemistry.

1. any of a group of enzymes that catalyze the cleavage of DNA molecules at specific sites: used for gene splicing in recombinant DNA technology and for chromosome mapping.

restriction enzyme

noun

1. any of several enzymes produced by bacteria as a defence against viral infection and commonly used to cut DNA for genetic manipulation or diagnosis

Word History and Origins

Origin of restriction enzyme¹

First recorded in 1960–65

Example Sentences

The host DNA is sliced open, the plasmid is inserted in the gap, and ligases repair the cut made by the restriction enzymes.

From Popular-Science

One hypothesis is that replacing A with Z is a countermeasure against bacterial defense enzymes, known as restriction enzymes, that chop up DNA from invading phages.

From Science News