CRYSTALLIZATION AND PRELIMINARY-X-RAY DIFFRACTION STUDIES OF HUMAN RANTES

The chemotactic cytokine RANTES (Regulated on Activation, Normal T-cel l Expressed and Secreted) is a potent chemoattractant and activator of a number of leukocytes, with a molecular mass of 8 kDa. Crystals of t his protein have been grown from 100 mM sodium acetate buffer (pH 4.6) containing 200 mM magnesium acetate, with 20% (w/v) PEG 4000 and 6% ( v/v) glycerol. The crystals grow as thick rods, which diffract to at l east 1.8 Angstrom resolution on a rotating anode X-ray source. The cry stals belong to space group P2(1)2(1)2(1) with unit cell dimensions a = 95.14 Angstrom, b = 57.58 Angstrom and c = 24.01 Angstrom with alpha = beta = gamma = 90 degrees. The asymmetric unit contains two molecul es of the RANTES monomer, with a V-M of 2.0 Angstrom(3)/Da.