Reactions of the lectin anti-AHP from the edible snail Helix pomatia with N-acetyl-D-galactosamine of streptococci.

The lectin anti-AHP obtained from the albumen gland of the edible snail, Helix pomatia, was used for the routine identification of group C streptococci. Without any exception all 1,045 strains of group C streptococci (S.equisimilis, and S.zooepidemicus, and S.dysgalactiae) were agglutinated by the Helix lectin, but none of the 12,264 strains of group A, 1,346 strains of group G, 330 strains of group B as well as that of other streptococcal groups. The presence of type-specific T antigens of group A streptococci in group C streptococci does not influence the agglutinability of S.equisimilis (group C). A few but not all strains of S.milleri either carrying or not group G specific carbohydrate and S.sanguis with group H antigen were agglutinated by the Helix lectin Anti-AHP. This suggests that terminal N-acetyl-D-galactosamine of these bacteria reacted with the Helix lectin (Anti-AHP). Therefore the Helix lectin is very useful tool for identification of group C streptococcus as well as for immunological studies.