Restriction enzyme

A restriction enzyme is an enzyme that can cut ribonucleic acids, usually double-stranded DNA. The position where the enzyme cuts the DNA is determined by a pattern of nucleotides specific to the enzyme. Cuts can either result in blunt or sticky ends:

Original sequence

GTCAGCCTGAGTCTGATGCTGAC
CAGTCGGACTCAGACTACGACTG

Blunt ends

GTCAGCCTG AGTCTGATGCTGAC
CAGTCGGAC TCAGACTACGACTG

Sticky ends

GTCAGCCTG AGTCTGATGCTGAC
CAGTCGGACTCAGAC TACGACTG

Today, restriction enzymes are an essential tool (like scissors) in molecular biology.