EcoRI

EcoRI (pronounced "eco R one") is a type II restriction enzyme isolated from Escherichia coli. It cleaves DNA double helices into fragments at specific sites, and is also a part of the restriction modification system. The enzyme's name originates from the species from which it was isolated: "E" denotes generic name (Escherichia), "co" denotes species name (coli), "R" represents the strain (RY13), and the "I" denotes that it was the first enzyme isolated from this strain.

In molecular biology it is used for restriction digests. EcoRI creates sticky ends with 5' end overhangs of AATT. The nucleic acid recognition sequence where the enzyme cuts is G↓AATTC, which has a palindromic complementary sequence of CTTAA↓G.