Macromolecular cues in marine systems.

A review of the roles of biopolymers as marine chemical cues is presented. The goal of the review is to provide a context within which to view present research and to provide insight into future research potential for macromolecules in marine chemical ecology. The roles of peptides, proteins, glycoproteins, proteoglycans, lectins, and mucopolysaccharides are discussed. Biological events mediated include: larval settlement and metamorphosis, gamete attraction, predator-prey interactions, alarm responses, feeding responses, nonfood resource acquisition, trail following, and larval-release behavior. Molecular origins, transmission, modulation, and multifunctionality of cues are discussed and illustrated with specific examples. The advantages of biopolymers, especially peptides and proteins, as specific cues in marine systems derive from their solubility, specific information content (due to the asymmetric nature of the monomer and the wordlike information content of the primary structure of the polymer), distance transmission in water by bulk flow rather than diffusion, relatively high signal-to-noise ratio, and common occurrence as structural and metabolic components of all living organisms.