FIGURE 3.

Reactivity of selected lectins with N-linked oligosaccharides. Scheme of reactivity of gp120 after digestion with PNGase F (to remove all N-linked oligosaccharides), Endo H (to cleave only high-mannose and hybrid oligosaccharides), or neuraminidase (to remove sialic acid). Reactivities of lectins GNL, AAL, PHA-L, and Sambucus nigra agglutinin (SNA) with high-mannose or hybrid (A) and complex (B) oligosaccharides are based on recognition of specific oligosaccharide structures remaining on gp120 after treatment with specified glycosidase. For simplicity, the reactivity is expressed as plus (+) or minus (−).