ABSTRACT
Factor in the Coral-Zooxanthellae Symbiosis .................................................................. 234 16.3.1 Isolation and Chemical Properties of S. lochmodes Lectin, SLL-2 .................... 234 16.3.2 Cloning of cDNA-Encoding SLL-2 ..................................................................... 235 16.3.3 Localization of SLL-2 in S. lochmodes ............................................................... 235 16.3.4 Activity of SLL-2: In-Culture Experiment against Symbiodinium ..................... 235 16.4 Conclusion and Future Directions ..................................................................................... 237 References .................................................................................................................................... 239
In marine invertebrates, lectins, especially those in the hemolymph, are believed to contribute as nonself recognition factors in their defense mechanisms [1,2]. Moreover, there is an increasing number of evidence supporting that the marine invertebrate lectins are involved also in various endogenous processes such as embryonic developments [3] and biomineralization [4] together with self and nonself recognition. Lectins are also thought to be involved in extracellular biological events as well. Some lectins of marine invertebrates such as giant clams [5], sponges [6], and tunicates [7] are proposed to mediate the interaction between invertebrate hosts and symbiotic bacteria or microalgae. Because of the property of lectins that can recognize speci c surface carbohydrate chains, it is feasible to postulate that lectins function as chemical factors in recognition of speci c microorganisms by a host. In fact, an idea that lectins mediate the recognition between legumes and nitrogen- xing bacteria has been reinforced by recent molecular biological evidence [8]. It is thus tempting to assume that lectin-mediated symbioses between marine invertebrate hosts and microorganisms are rather general phenomena.
