| Autor: |
A, Stapleton, D T, Blankenship, B L, Ackermann, T M, Chen, G W, Gorder, G D, Manley, M G, Palfreyman, J E, Coutant, A D, Cardin |
| Rok vydání: |
1990 |
| Předmět: |
|
| Zdroj: |
The Journal of biological chemistry. 265(4) |
| ISSN: |
0021-9258 |
| Popis: |
Three polypeptide neurotoxins (curtatoxins) were isolated from the venom of the spider Hololena curta by reverse-phase high performance liquid chromatography, gel permeation, and ion-exchange chromatography. The purified toxins induced an immediate paralysis in the cricket Acheta domestica that resulted in desiccation and death of the insect within 24-48 h (LD50 congruent to 4-20 micrograms/g); this toxic effect is consistent with irreversible presynaptic neuromuscular blockade. Curtatoxins are a class of sequence-related, cysteine-rich, carboxyl-terminal amidated polypeptides of 36 to 38 amino acid residues. The cysteine residues are conserved at identical sequence positions among these polypeptides and form 4 intramolecular disulfide bonds. Hydropathy calculations show that the toxins have an internal hydrophobic region flanked by hydrophilic and oppositely charged amino- and carboxyl-terminal ends. By analogy to other cysteine-rich arthropod venom proteins, the folded structure of the curtatoxins is likely important for their target specificity and mode of action at the neuromuscular junction. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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