Crystallization and preliminary X-ray diffraction analysis of human growth and differentiation factor 5 (GDF-5)

Abstract

Growth and differentiation factor 5 (GDF-5) belongs to the large TGF-beta superfamily of secreted signalling proteins and plays a pivotal role in skeletal development during embryogenesis. The gene for human GDF-5 was cloned, expressed in Escherichia coli and purified to homogeneity. Crystals were obtained that diffracted to 2.2 A resolution. A native data set was acquired, showing that the crystals belong to a trigonal space group, i.e. P3(1)21 or P3(2)21, with unit-cell parameters a = b = 97.1, c = 48.3 A. Initial analysis suggest the presence of only one monomer in the asymmetric unit, resulting in a high solvent content of 72% in the crystal.

Figure 1

Crystals of human GDF-5 grown in 25% MPD and 0.1 M sodium citrate pH 4.0 using the hanging-drop method. Dimensions of the crystal are approximately 0.4 × 0.07 × 0.07 mm.

Figure 2

X-ray diffraction pattern obtained for the crystal in Fig. 1 ▶; the crystal-to-detector distance was 190 mm and the resolution limit at the edge of the diffraction image is 2.25 Å.