Three sequence-specific endonucleases fromEscherichia coliRFL47

Abstract
The characterization of the new restriction enzyme Eco47III recognizing a hexanucleotide palindromic sequence 5'AGC↓GCT and cleaving, as indicated by the arrow, is reported. It was isolated from Escherichia coli strain RFL47. Another two specific endonuclease Eco47I (isoschizomer of AvaII) and Eco47II (isoschizomer of AsuI) were also found in this strain. There are two Eco47III recognition sites on λ DNA at 20997 and 37060 basepairs. The central Eco47III fragment can be replaced by a cloned fragment in λ vector mutant in tR2 gene; i.e., λ g