PURIFICATION, CRYSTALLIZATION AND PRELIMINARY-X-RAY ANALYSIS OF A MANNOSE-BINDING LECTIN FROM BLUEBELL (SCILLA-CAMPANULATA) BULBS

Crystals have been grown of a mannose-specific lectin from bluebell (S cilla campanulata) bulbs in a form suitable for X-ray diffraction stud ies. The crystals, which diffract to high resolution, grew in hanging drops by vapour diffusion, equilibrating with a solution of 70% satura ted ammonium sulfate at pH 4.7-4.8 at 293 K, in the absence of any man nose saccharides. Crystals are orthorhombic, P2(1)2(1)2, with unit-cel l dimensions a=70.78, b=93.69, c=46.92 Angstrom. The functional lectin molecule is organized as a tetramer of four identical 14 kDa subunits , with only two subunits in the asymmetric unit. Data to 1.86 Angstrom resolution have been recorded and the structure determined by the mol ecular replacement method.