Crystallization and preliminary diffraction analysis of the HincII restriction endonuclease-DNA complex

Crystals of the 60 kDa dimeric HincII restriction enzyme bound to a 12 base-pair dyad-symmetric duplex DNA carrying the specific 5'-­GTCGAC recognition site have been obtained. Crystals grew by hanging-drop vapor diffusion from solutions containing polyethylene glycol 4000 as precipitating agent. The rod-shaped crystals belong to space group I222 (or I2₁2₁2₁), with unit-cell dimensions a = 66.9, b = 176.7, c = 256.0 Å. There are most likely to be two dimeric complexes in the asymmetric unit. A complete native data set has been collected from a high-energy synchrotron source to a resolution of 2.5 Å at 100 K, with an R_merge of 4.8%.