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Updated: Jun 26, 2026

Identification of Hemolytic and Phospholipase Activity in Crude Extracts from Sea Anemones by Straightforward Bioassays
Published on: March 29, 2022
Sodium channel inhibiting marine toxins
1Australian Institute of Marine Science, Townsville MC, QLD 4810, Australia. L.Llewellyn@aims.gov.au
Abstract:
Saxitoxin (STX), tetrodotoxin (TTX) and their many chemical relatives are part of our daily lives. From killing people who eat seafood containing these toxins, to being valuable research tools unveiling the invisible structures of their pharmacological receptor, their global impact is beyond measure. The pharmacological receptor for these toxins is the voltage-gated sodium channel which transports Na ions between the exterior to the interior of cells. The two structurally divergent families of STX and TTX analogues bind at the same location on these Na channels to stop the flow of ions. This can affect nerves, muscles and biological senses of most animals. It is through these and other toxins that we have developed much of our fundamental understanding of the Na channel and its part in generating action potentials in excitable cells.
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