| restriction enzyme | |
| —n | |
| any of several enzymes produced by bacteria as a defence against viral infection and commonly used to cut DNA for genetic manipulation or diagnosis | |
| a scrap or morsel of food left at a meal. |
| a screen or mat covered with a dark material for shielding a camera lens from excess light or glare. |
restriction enzyme re·stric·tion enzyme (rĭ-strĭk'shən)
n.
Any of a group of enzymes that cleave DNA at specific sites to produce discrete fragments, used especially in gene-splicing. Also called restriction endonuclease.
Chemicals used in the lab to cut up DNA at specific sites so that it may be sequenced. They function in nature as a form of bacterial self-protection that can cut up foreign DNA. The use of restriction enzymes is crucial in DNA fingerprinting.