Blue-ringed octopus

Hwang DF, Arakawa O, Saito T, Noguchi T, Simidu U, Tsukamoto K, Shida Y, Hashimoto K. (1988) Tetrodotoxin-producing bacteria from the blue-ringed octopus Octopus Maculosus. Marine Biology 100 327-332. 

Flow Diagram for Isolation of Tetrodotoxin from the Blue Ring Octopus Hapalochlaena maculosa (23)... 

A bite is nearly painless, but will break the skin in most cases. The venom is not injected, but enters the wound via the saliva. The venom applied by the blue ring octopus is not produced by itself, but by bacteria inhabiting the salivary glands of the octopus. The bacteria is transferred from the mother to the young and even the eggs contain sufficient amounts of venom to be harmful. The venom has two components that can be separated by simple means. The first is most effective on crustaceans but harmless to humans. The other is similar to the toxin present in the Pufferfish and serves to as a defense against predatory animals. 

Hapalochlaena Maculosa Common Name(s) Southern Blue Ring Octopus... 

Produced by the blue ringed octopus and now known to be identical with tetrodotoxin qv. 

The fargefs for natural biological toxins include ion channels and receptors for transmitfers. At least four parts of fhe volfage-gafed sodium charmels are binding sifes for extremely toxic natural products. " Tetrodotoxin (Fig. 30-16), which is found in the puffer fish, certain newts, and venom of fhe blue-ringed octopus, and also the shellfish poison saxitoxin (Fig. 

Walker DG. Survival after severe envenomation by the blue-ringed octopus (Hapalochlaena maculosa). Med J Austral 2 663-665, 1983. 

Sheumack DD, Howden MEH, Spence I, Quinn RJ. Tetrodotoxin in the blue-ringed octopus. MedJAust 1 160-161, 1978. 

Blue-ringed octopus Hapalochlaena Octopus) maculosus (Family Octopodidae) has so far been identified as the only lethal and TTX-bearing octopus. It is found in shallow coral and rock pools in the waters aroimd Japan, Taiwan, Philippines, and Australia. This octopus probably produces a poison in the salivary glands, which seems to be used for hunting and defense purposes. Many researches attempted to elucidate the causative agent of human fatalities attributed to the bite from this species. Although, it was initially claimed to be the new toxin. 

All octopuses generally have ink sac where a lot of ink is pooled. When they meet enemy or are attacked by them, they secrete a lot of ink from their sac and can conceal themselves to escape. Since they have a strong defense substance of TTX and need not use ink, the sac has lost above function. Significance why this blue-ringed octopus has TTX seems to use TTX for capturing preys or defensing itself from enemy. 

Attempts were also made to isolate TTX-bearing bacteria from the blue-ringed octopus O. maculosus from the Philippines (Hwang et al, 1989). The results showed that 16 of the 22 isolated strains produced TTX and/or related substances. Six of the 16 strains produced TTX and/or related substances. Six of the 16 strains were classified into the genera of Vibrio, Pseudomonas, and two each of Alteromonas and Bacillus. 

In 1978, TTX was isolated from the posterior salivary gland of the blue-ringed octopus (O. maculosus), which mainly inhabits northern Australia. Human TTX cases are occasionally reported in this area due to envenom-ation by 0. maculosus. This octopus also occasionally appears in middle to south Japan. The octopus secretes TTX from the posterior salivary gland to paralyze its prey. 

Hwang, D.F., Arakawa, O., Saito, T., Noguchi, T., Simidu, U., Tsukamoto, K., Shida, Y., and Hashimoto, K. 1989. Tetrodotoxin-producing bacteria from the blue-ringed octopus. Octopus maculosus. Mar. Biol 100, 327-332. 

Sheumack, D.D., Howden, M.E.H., and Spence, I. 1984. Occurrence of a tetrodotoxi-like compound in the eggs of the venomous blue-ringed octopus Hapalochlaena maculosa. Toxicon 2, 811-812. 

Sutherland, S.K. and Lane, W.R. 1969. Toxins and mode of envenomation of the common ringed or blue-ringed octopus. Med. J. Aust. 1, 893-898. 

Tetrodotoxin has been isolated from various vertebrate and invertebrate species, among them from the blue-ringed octopus, Hapaloch-laena maculosa. Sheumack et al. (614) described the occurrence of a lethal toxin in the eggs of this species. The properties of this toxin were indistinguishable from those of authentic tetrodotoxin. 

Sheumack, D.D., M.E.H. Howden, and I. Spence Occurrence of a Tetrodotoxin-Like Compound in the Eggs of the Venomous Blue-ringed Octopus Hapalochlaena maculosa). Toxicon 22, 811 (1984). 

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