Amino-acid sequence of the minor neurotoxin from Acalyptophis peronii venom.

Sea snakes, Acalyptophis peronii, were captured in the Gulf of Thailand and their venom was isolated. A. peronii venom contains two neurotoxins called major and minor toxin. The complete amino-acid sequence of the minor toxin was identified and compared to that of the major toxin. The only difference between the major and the minor toxins is in the 43rd residue. The major toxin at this position contains glutamine, while the minor toxin contains glutamic acid. The LD50 of the minor toxin is 0.170 microgram/g in mice when injected intravenously. The toxicity is slightly lower than that of the major toxins, which has an LD50 of 0.125 microgram/g.