Bioactive peptides from Gemmula speciosa venom: Isolation, purification, and sequencing

Turrids comprise the largest group of venomous gastropods in superfamily Conacea, the others being augers (Terebridae) and cones (Conidae). They are a hallmark of diversity with some turrid shells looking like cones and others resembling mitrids, fasciolarids or buddinids; although one feature common among them is the presence of a notch or sinus in the body whorl. Turrids are carnivorous marine gastropods preying largely on polychaete worms. Their well-developed venom apparatus endows them the ability to effectively capture their prey through a specialized delivery system of their venom via a radula, thereby eliciting effects like paralysis prior to swallowing their victim. This feeding mechanism, also prevalent in Conus species, where they paralyze their prey by blocking voltage-gated ion channels on nerve membranes with venom toxins, had been well­ characterized more than two decades ago. The biologically active venom toxins were found to be highly structured cysteine-rich peptides with physiological targets on prey or predators/competitors (Olivera, 2002). Unlike the coniids, however, the turrid venom toxins, as well as their physiological targets, functions and applications, are largely unknown and are only beginning to be explored. As part of a continuing effort to gain understanding of the turrid toxinology, this study aims to isolate, purify, and characterize bioactive components of the venom duct of Philippine turrid Gemmula speciosa, which could be a promising source of neuractive peptides for therapeutic applications. Preliminary results on the isolation, purification and biochemical characterization of venom components are reported