NPL, isolated from daffodil bulbs, has a specificity toward α-linked mannose, preferring polymannose structures containing (α-1,6) linkages. Binding to mannose polymers can occur via internal mannose residues and is not dependent on structural integrity of a non-reducing end sugar. NPL also binds some galactomannans, and differs in other binding characteristics from a related lectin, Galanthus nivalis lectin. Unlike Con A, LCA, or PSA, NPL does not bind glucose.