ISOLATION, PURIFICATION, AND CHARACTERIZATION OF A NEW MANNOSE-BINDING PLANT LECTIN THAT RECOGNIZES FUNGAL ANTIGENS

Lectins, found throughout the living world, belong to a group of carbohydrate (glycan) binding proteins that selectively recognize glycosylated proteins and lipids. Ligand specificity allows lectins to participate in a variety of biological functions. Our lab identified a new plant lectin named PD in a monocotyledonous plant native to South America. PD, purified by affinity chromatography and by “Capture and Release” (CaRe), is a heterotetramer of 10 kDa and 12 kDa subunits. PD binds to oligomannosides and high mannose-containing glycoproteins with high affinity. Light microscopy and FE-SEM imaging was utilized to monitor the agglutination activity of PD towards rabbit erythrocytes and yeast cells. The high affinity for fungal antigens (mannan) and invertase led us to hypothesize that PD could be an endogenous defensive protein or a metabolic regulator. PD can be used as a detection tool for clinically important mannoglycoproteins such as IgM, Covid S-protein and HIV gp120