ASV integrase catalytic domain
Bujacz G., Jaskolski M., Alexandratos J., Wlodawer A., Merkel G., Katz R.A. & Skalka A.M. (1996).
The catalytic domain of avian sarcoma virus integrase: conformation of the active-site residues in the presence of divalent cations.
Structure 4, 89-96.
See also -
Grindley, N. D. & Leschziner, A. E. (1995).
DNA transposition: from a black box to a color monitor. 
Cell 83, 1063-1066.