Purification and pharmacological properties of eight sea anemone toxins from Anemonia sulcata, Anthopleura xanthogrammica, Stoichactis giganteus and Actinodendron plumosum

Abstract

Eight different polypeptide toxins from sea anemones of four different origins (Anemonia sulcata, Anthopleura xanthogrammica, Stoichactis giganteus, and Actinodendron plumosum) have been studied. Three of these toxins are new; the purification procedure for the five other ones has been improved. Sea anemone toxins were assayed (i) for their toxicity to crabs and mice, (ii) for their affinity for the specific sea anemone toxin receptor situated on the Na+ channels of rat brain synaptosomes, and (iii) for their capacity to increase, in synergy with veratridine, the rate of 22Na+ entry into neuroblastoma cells via the Na+ channel. Some of the toxins are more active on crustaceans, whereas others are more toxic to mammals. A very good correlation exists between the toxic activity to mice, the affinity of the toxin for the Na+ channel in rat brain synaptosomes, and the stimulating effect on 22 Na+ uptake by neuroblastoma cells. The observation has also been made that the most cationic toxins are also the most active on mammals and the least active on crustaceans. Toxicities (LD50) to mice of the most active sea anemone toxins and of the most active scorpion toxins are similar, and sea anemone toxins at high enough concentrations prevent binding of scorpion toxins to their receptor. However, scorpion toxins have affinities for the Na+ channel which are approximately 60 times higher than those found for the most active sea anemone toxins. Three sea anemone toxins appear to be more interesting than toxin II from A. sulcata (the "classical" sea anemone toxin) for studies of the Na+ channel structure and mechanism when the source of the channel is of a mammalian origin. Two of these three toxins can be radiolabeled with iodine while retaining their toxic activity; they appear to be useful tools for future biochemical studies of the Na+ channel.

The secondary structure of the toxin ATX Ia from Anemonia sulcata in aqueous solution determined on the basis of complete sequence‐specific 1H‐NMR assignments

“…ATX I was extracted from the venom of Anemoniu sulcata and purified as described elsewhere [27]. In a further purification step the two polypeptides with either Ala (ATX Ia) or Pro (ATX Ib) in position 3 ( Fig.…”

A polypeptide toxin from the coral Goniopora

“…It may be that the toxin is more active on Ca2+ channels of animals of marine origin. Affinities for other polypeptide toxins on Na+ channels are also known to be very dependent on the animal species [28,29].…”

Specificity of antibodies to sea anemone toxin III and immunogenicity of the pharmacological site of anemone and scorpion toxins

“…In spite of its hydrophobic character, and it most probable overall rigidity, ATX I11 is immunogenic. From a pharmacological point of view ATX I, I1 and I11 are highly toxic to crabs [26] and ATX I1 binds specifically to receptor sites at the level of the sodium channel and can displace Androctonus australis Hector scorpion a-toxin I1 from its receptor sites. There is, however, no sequence similarity between ATX I11 and ATX 11.…”