This family consists of the defensin-like peptides (DLPs) isolated from platypus venom. These DLPs show similar three-dimensional fold to that of beta-defensin-12 and sodium-channel neurotoxin Shl. However the side chains known to be functionally important to beta-defensin-12 and Shl are not conserved in DLPs. This suggests a different biological function. Consistent with this contention, DLPs have been shown to possess no anti-microbial properties and have no observable activity on rat dorsal-root-ganglion sodium-channel currents.