Quaternary structure of UEA-II, the chitobiose specific lectin from gorse.

The chitobiose specific Ulex europaeus lectin II crystallizes in space group P3221 with unit-cell dimensions a = b = 105.54, c = 176.26 A. The asymmetric unit contains a complete lectin tetramer. The crystals were shown to diffract to 4.5 A on a rotating-anode source and to 2.7 A at the Daresbury synchrotron source. Molecular replacement and subsequent rigid-body refinement using data to 4.5 A yielded a solution corresponding to a tetramer very similar to that of phytohemagglutinin-L and soybean agglutinin. The monomers in the Ulex lectin tetramer are rotated approximately 5 degrees compared with the phytohemagglutinin-L and soybean agglutinin structures.