Crystallization and preliminary X-ray studies of a galactose-specific lectin from the seeds of Spatholobus parviflorus

A galactose-specific seed lectin was purified from the legume Spatholobus parviflorus and crystallized using the hanging-drop vapour-diffusion technique. The crystals belonged to space group P1, with unit-cell parameters a = 60.998, b = 60.792, c = 78.179 Å, α = 101.32, β = 91.38, γ = 104.32°. X-ray diffraction data were collected under cryoconditions (100 K) to a resolution of 2.04 Å using a MAR image-plate detector system mounted on a rotating-anode X-ray (Cu Kα) generator. Molecular replacement using legume-lectin coordinates as a search model gave a tetrameric structure.