Crystallization and preliminary X-ray diffraction studies of dogfish C-reactive protein

Crystals of dogfish (Mustelus canis) C-reactive protein were obtained through vapor phase equilibration using the sitting drop rod technique with ammonium sulfate as the precipitating agent. The space group was determined to be P1 (triclinic lattice) with unit cell dimensions of a = 82.91, b = 92.25 and c = 103.40 A; alpha = 83.36 degrees, beta = 89.76 degrees, and gamma = 81.30 degrees. These crystals diffract to about 2.6 A resolution and contain two hexamers in the asymmetric unit.