Buccitoxins and muritoxins: Conotoxin-like peptides in non-conoidean venoms revealed with a novel bioassay

Abstract Salivary venom samples were obtained from the radular glands of Lightning Whelk (Sinistrofulgur perversum), Apple Murex (Phyllonotus pomum), and Pear Whelk (Fulguropsis spirata) specimens. Extraction was performed via pressure application to the mid-esophageal and accessory salivary glands. The Apple Murex belongs to the superfamily Muricoidea, while the Lightning and Pear Whelks belong to Buccinoidea. It was hypothesized that the overall structural characteristics of their venomic peptidomes would mirror those of conotoxins. Peptidomes extracted via (NH)₂SO₄ precipitation were preprocessed by centrifugation and analyzed using the novel Levensaler Immobilized Metal Chelate Affinity Labelling Assay (LIMCALA). This assay was specifically designed for high-level Neogastropod venomic analyses in field environments, such as research vessels, where HPLC-MS is impractical. The resulting data, processed through the Levensaler Neogastropod Venomic Similarity Indexing (LNVSI) machine-learning algorithm, yielded high, statistically significant composite similarity scores against an α-conotoxin VxXXC positive control. These findings strongly suggest the presence of buccinoidean and muricoidean conotoxin-like myotoxins, termed “buccitoxins” and “muritoxins”, warranting further investigation into their pharmacological potential.