Crystallization and preliminary X-ray analysis of human leukocyte cell-derived chemotaxin 2 (LECT2)

Human leukocyte cell-derived chemotaxin 2 (LECT2) is a chemotactic factor for neutrophils that plays multifunctional roles in liver regeneration, regulation of neuritic development and proliferation of chondrocytes and osteoblasts. In addition, the C-terminal region of LECT2 belongs to the zinc metalloendopeptidase M23 (PF01551) family. Purified LECT2 was crystallized using the sitting-drop vapour-diffusion method at 293 K. Crystals of selenomethionine-substituted LECT2 that diffracted X-rays to 1.94 Å resolution were obtained using a reservoir solution consisting of 0.2 M ammonium sulfate, 0.1 M HEPES pH 7.5, 25%(w/v) PEG 8000. The crystal belonged to space group P2₁2₁2₁, with unit-cell parameters a=59.4, b=63.5, c=64.0 Å. The calculated Matthews coefficient (VM=2.10 Å3 Da(-1), solvent content 40%) indicates that the crystal consists of two molecules per asymmetric unit.