PMID: 12379841 , Related PDB ids: 1LNO, 1MK0, E75A, R27A

Authors:

Van Roey P, Meehan L, Kowalski JC, Belfort M, Derbyshire V

Title:

Catalytic domain structure and hypothesis for function of GIY-YIG intron endonuclease I-TevI.

Journal:

Nat Struct Biol. 2002 Nov;9(11):806-11.

Abstract:

I-TevI, a member of the GIY-YIG family of homing endonucleases, consists of an N-terminal catalytic domain and a C-terminal DNA-binding domain joined by a flexible linker. The GIY-YIG motif is in the N-terminal domain of I-TevI, which corresponds to a phylogenetically widespread catalytic cartridge that is often associated with mobile genetic elements. The crystal structure of the catalytic domain of I-TevI, the first of any GIY-YIG endonuclease, reveals a novel alpha/beta-fold with a central three-stranded antiparallel beta-sheet flanked by three helices. The most conserved and putative catalytic residues are located on a shallow, concave surface and include a metal coordination site. Similarities in the three-dimensional arrangement of the catalytically important residues and the cation-binding site with those of the His-Cys box endonuclease I-PpoI suggest the possibility of mechanistic relationships among these different families of homing endonucleases despite completely different folds.