Drug Discovery in Exotic Marine Symbionts

Rare and exotic marine organisms have proven to be a promising source of new drugs and other bioactive compounds. Haygood and collaborators have discovered that giant shipworms and other mollusks harbor a rich ecosystem of symbiotic bacteria, and that the symbiotic relationships between marine bacteria and marine animals are based on chemical signals exchanged between mollusks, for instance, and their bacterial symbionts. The discoveries garnered significant attention owing to their potential for providing rich platforms for drug discovery. The "wooden-steps" hypothesis proposed that large chemosynthetic mussels found at deep-sea hydrothermal vents descend from much smaller species associated with sunken wood and other organic deposits and that the endosymbionts of these progenitors made use of hydrogen sulfide from biogenic sources (e.g., decaying wood) rather than from vent fluids. The study of bacterial symbiosis in exotic organisms, such as shipworm mollusks, illustrates universal principles that may be applied to the human microbiome.