Bungarus multicinctus Bungarotoxins

Mixture of neurotoxins that block the acetylcholine receptors. The /3-bungarotoxin is a pre-synaptic neural toxin, a-bungarotoxin is a postsynaptic neural toxin, and K-bungarotoxin is specific to the neuronal receptors in ganglions. They are obtained from the venom of the banded krait (Bungarus multicinctus). 

The venom of the elapid snake Bungarus multicinctus (Southeast Asian banded krait) contains a-bungarotoxin, a protein composed fo 74 amino acids (about 8000 daltons) having five disulfide bridges. The LD50 in mice is 0.21 mg/g (s.c.)... 

Use of Toxin Binding to Purify a Channel Protein a-Bungarotoxin is a powerful neurotoxin found in the venom of a poisonous snake (Bungarus multicinctus). It binds with high specificity to the nicotinic acetylcholine receptor (AChR) protein and prevents the ion channel from opening. This interaction was used to purify AChR from the electric organ of torpedo fish. 

Protein components of the venom of the banded krait (Bungarus multicinctus). Two major components a- and (3-bungarotoxins. ct-Bungarotoxin binds irreversibly to ACh receptor causing neuromuscular blockade and muscle paralysis similar to effects of curare, p-Bungarotoxin contains several components prevents ACh release at skeletal neuromuscular junction. Crude venom LD50 SC mouse, 0.16 mg/kg bw. 

The venom of the Southeast Asian banded krait (Bungarus multicinctus) contains a-bungarotoxin, which binds exclusively and by high affinity to the nicotinic receptors. By means of these and many other substances, it is unveiled that insects and other invertebrates like the vertebrates have both types of acetylcholine receptors. 

Bungarotoxins. Toxins of the very poisonous southeast Asian snake Bungarus multicinctus (striped krait, Elapidae). Crude extract of venom LD50 (mouse s.c.) 0.019 to 0.33 mg/kg. The postsynaptic neurotoxin a-B. is a polypeptide (Mr ca. 8000) of 74 amino acids and 5 disulfide bridges exhibiting curare-like activity. jS-B. contains different polypeptides and is a pre-synaptic neurotoxin. 

Chang, L. S., and Yang, C. C. (1988). Role of the N-terminal region of the A chain in p -bungarotoxin from the venom of Bungarus multicinctus (Taiwan-banded krait). J. Protein Chem. 7 713-726. 

Mebs, D., Narita, K., Iwanaga, S., Samejima, Y, and Lee, C. Y. (1971). Amino acid sequence of a-bungarotoxin from the venom of Bungarus multicinctus. Biochem. Biophys. Res. Commun. 44 711-716. 

Kondo, K., Toda, H., Narita, K. and Lee, C. Y. (1982b) Amino acid sequences of three P-bungarotoxins (P3-, P4- and P5-bungarotoxins) from Bungarus multicinctus venom amino acid substitutions in the A o i2 ns. J. Biochem. 1991, 1531-1548. 

A post-synaptic (a-bungarotoxin) and a pre-synaptic (p-bungarotoxin, phospholi-pase-A2) neurotoxins isolated from Bungarus multicinctus were ionized separately and their corresponding ESI spectra were recorded. The results are shown in Figure 5. The molecular mass of a-bungarotoxin was measured (7,983.4 0.6 Da) with minor (0.08%) error in comparison with the calculated value (7,990.4 Da). The measured molecular mass of P-bungarotoxin was (20,658.8 1.5 Da). 

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