[Modification of the neurotoxin RTX-III from the sea anemone Radianthus macrodactylus].
The influence of chemical modification on neurotoxin RTX-III toxicity in mice has been studied. The toxicity was not affected by modification of Trp30 residue with 2-hydroxy-5-nitrobenzyl bromide but was diminished by a factor of 100 after reduction of the toxin's two disulfide bonds with 2-mercaptoethanol followed by derivatization with iodoacetamide. Blocking carboxyl groups with [3H]glycine methyl ester in the presence of 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide led to only a two-fold drop in toxicity in the case of monocarboxylate-modified derivatives and a six-fold decrease for dimodified derivatives. A conception of multipoint attachment of the toxin to sodium channel is discussed.
Makhnyr'
V M
VM
Kozlovskaia
E P
EP
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D002942:Circular Dichroism; D003063:Cnidaria; D003064:Cnidarian Venoms / Q000032:analysis / Q000633:toxicity*; D004220:Disulfides / Q000032:analysis; D007928:Lethal Dose 50; D051379:Mice; D009498:Neurotoxins / Q000032:analysis / Q000633:toxicity*; D012615:Sea Anemones; D015222:Sodium Channels / Q000187:drug effects
D000596:Amino Acids; D003064:Cnidarian Venoms; D004220:Disulfides; D009498:Neurotoxins; D015222:Sodium Channels; C032104:toxin III (Anemonia sulcata)