Surugatoxin (SGTX) is a type of venom found in the mid-gut digestive gland of the Japanese ivory mollusk Babylonia japonica, a carnivorous gastropod.

[1] The structurally and functionally related neosurugatoxin, also derived from Babylonia japonica, is an even more potent nAChR antagonist than SGTX.

[6] SGTX is contained in the mid-gut digestive gland of the Japanese ivory mollusk, Babylonia japonica, which is used as an ingredient in sushi and sashimi.

Kosuge and colleagues[7] found that these toxins are actually the metabolized products of a marine bacterium that belongs to the Coryneform group.

A number of researchers have characterized the effect of surugatoxin on behavior and physiology in animal models[1][4] SGTX causes disturbances in gait, suppression of spontaneous motility, and mydriasis in mice at intravenous (i.v.)

Ascher and colleagues[9] posit that ganglionic blockade by SGTX results from binding to the closed state of the channel-receptor complex, possibly to the receptor itself.