[1] EcoRII is a bacterial Type IIE[2] REase that interacts with two[3] or three[4] copies of the pseudopalindromic DNA recognition sequence 5'-CCWGG-3' (W = A or T), one being the actual target of cleavage, the other(s) serving as the allosteric activator(s).

EcoRII cuts the target DNA sequence CCWGG, generating sticky ends.

[5] The apo crystal structure of EcoRII mutant R88A (PDB: 1NA6​)[6] has been solved at 2.1 Å resolution.

The N-terminal effector-binding domain has an archetypal DNA-binding pseudobarrel fold (SCOP 101936) with a prominent cleft.

Structural superposition showed it is evolutionarily related to: The C-terminal catalytic domain has a typical[10] restriction endonuclease-like fold (SCOP 52979) and belongs to the large (more than 30 members) restriction endonuclease superfamily (SCOP 52980).