Crystallization and preliminary X-ray analysis of the tumour necrosis factor alpha-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 alpha (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 P2(1)2(1)2(1), with unit-cell parameters a = 74.5, b = 117.4, c = 246.8 A. Assuming the presence of two TNF-TNFR2 complexes in the asymmetric unit, the Matthews coefficient V(M) was 2.49 A(3) Da(-1) and the solvent content of the crystal was 50.7%. The crystal diffracted to 2.95 A resolution.