PMS-ICBG Researchers discover that symbiotic bacteria provide bioactive molecules to their hosts in shipworms and cone snails
Two New Breakthroughs Demonstrate How Tomorrow’s Life-Saving Medications May Currently Be Living At the Bottom of the Sea
Mollusks, which include animals such as clams and snails, usually have hard shells to protect them from attack. Generally they are thought not to rely heavily on chemical defenses and are not often studied for discovery of new chemicals for drug development.
Two recent studies from the Philippine Mollusk Symbiont ICBG project show that mollusks can contain exciting chemistry, and that bacteria associated with the mollusk produce the chemical compounds.
In an article published online in Proceedings of the National Academy of Sciences, USA, PMS-ICBG researchers from Oregon Health & Science University, University of the Philippines, University of Utah and Ocean Genome Legacy, along with Brazilian and Egyptian collaborators, report the discovery of a boron-containing antimicrobial compound called tartrolon from a bacterial symbiont of shipworms. Shipworms are clam-like mollusks that burrow into and consume wood, and the importance of their bacterial symbionts in their nutrition has long been known. The discovery that the bacteria produce antimicrobial compounds, too, was a surprise. Because the compound could be directly detected in the shipworm, it appears likely to play an important role in the system. The authors suggest it may suppress bacteria that compete with the shipworm for the sugars produced by the digestion of wood, or to protect the symbiont from competing bacteria in their home in the animal’s gills.
In another article published in Chemistry and Biology, PMS-ICBG researchers from University of Utah, University of the Philippines, and Oregon Health & Science University report the discovery of a bacterium associated with a venomous cone snail from the Philippines that produces nocapyrones that are abundant in the host animal tissues. The value of the nocapyrones to the host is unknown, but in laboratory tests, they have neurological activity.
Together these two studies demonstrate that bacteria associated with mollusks are a good source of new molecules for drug development; molecules which over millions of years, have been selected to do their job without hurting the host. Furthermore, these bacteria, with their chemical prowess, are probably important in the ability of their hosts to survive and prosper.