Crystallization and preliminary X-ray analysis of the tumour necrosis factor α–tumour necrosis factor receptor type 2 complex

Tumour necrosis factor receptor type 2 (TNFR2, TNFRSF1B) is an essential receptor for various host-defence functions of tumour necrosis factor α (TNF). As part of studies to determine the structure of TNFR2, the formation, crystallization and preliminary X-ray diffraction analysis of the TNF–TNFR2 complex are described. The TNF–TNFR2 complex, which comprises one TNF trimer and three TNFR2 monomers, was confirmed and purified by size-exclusion chromatography. Crystals of the TNF–TNFR2 complex were obtained using polyethylene glycol 3350 as a precipitant. The crystal belonged to space group P2₁2₁2₁, with unit-cell parameters a = 74.5, b = 117.4, c = 246.8 Å. Assuming the presence of two TNF–TNFR2 complexes in the asymmetric unit, the Matthews coefficient V_M was 2.49 ų Da⁻¹ and the solvent content of the crystal was 50.7%. The crystal diffracted to 2.95 Å resolution.