Binding characteristics of lectins involved in the trapping of nematodes by fungi

Seventeen saccharides were tested for their ability to bind to the trap lectins of three species of nematode-trapping fungi and prevent nematode capture. The lectin of Arthrobotrys conoides was found to be inhibited by alpha-d-glucose/d-mannose and similar saccharides. The lectins of Monacrosporium eudermatum and Monacrosporium rutgeriensis were inhibited by alpha-l-fucose and 2-deoxy-d-glucose, respectively. Human group O(H) erythrocytes agglutinated to traps of M. eudermatum but not A. conoides or M. rutgeriensis. There was no agglutination of group A or B to traps formed by all three fungi. Exposure of the traps to trypsin eliminated the ability to capture nematodes. The presence of d-glucose/d-mannose and l-fucose residues on the nematode cuticle was suggested through the use of commercially prepared lectin-peroxidase conjugates.