Isolation and partial characterization of latex lectins from three species of the genus Euphorbia (Euphorbiaceae)

Three N-acetylgalactosamine-specific lectins were isolated from the latices of Euphorbia calcina L., Euphorbia dalberi L. and Euphorbia sp. (an undetermined species) by affinity chromatography on fetuin-agarose. They are all glycoproteins [about 12.5% (w/w) carbohydrate] of M, around 140 000 and appear to be tetrameric molecules composed of different subunits. All three lectins have similar amino acid (with high contents of asparagine/aspartic acid, giycine and leucine) and carbohydrate (with glucosamine, mannose.) fucose and xylose) compositions. In addition. they are closely related serologically.