Interaction of lectins from gonads and haemolymph of the sea hare Aplysia with bacteria.

Gonads and haemolymph of two Mediterranean species of Aplysia (A. depilans and A. fasciata) contain lectins. A. depilans gonad lectin is specific for D-galacturonic acid and D-galactosides, while its haemolymph agglutinin binds N-acetylated sugars. A. fasciata gonad lectin is also specific for D-galacturonic acid, but its haemolymph haemagglutinin exhibits heterogenic specificity. Both Aplysia gonad lectin and haemolymph agglutinins interact with bacteria, including certain Escherichia coli strains, Bacillus subtilis, Pseudomonas aeruginosa strains and marine bacteria such as the light producing Vibrio harveyi and Photobacterium leiognathi, as well as marine bacteria cultured from the close environment of Aplysia.