Presence of serotonin in the venom of Conus imperialis

The bioactive components in the venoms of cone snails are largely small peptides which target to a diverse set of ion channels and neuronal receptors. We report here the presence of substantial levels of serotonin in the venom of the imperial cone snail, Conus imperialis. This venom also contains many small bioactive peptides. The identification of serotonin has been confirmed by mass spectroscopy, NMR, HPLC mobility and UV spectroscopy. Although serotonin has been reported in arthropod venoms, it was previously reported to be absent in Conus venoms. We examined a total of fourteen different Conus species, and found detectable serotonin only in the venom of C. imperialis. Conus imperialis specializes in feeding upon the amphinomid polychaete Eurythoe complanata. We speculate that serotonin may play a role in the capture of this prey.