The channel-forming component of the Theridiidae spider venom neurotoxins.
It is known that Steatoda (Lityphantes) paykulliana and Latrodectus mactans tredecimguttatus spider venoms are toxic to mammals and insects. These venoms act presynaptically eliciting massive release of transmitters. They also form channels in bilayer lipid membranes (BLM) that are selective for cations. Venoms of both spider species were fractionated by gel filtration on a Sephadex G-100 column. The fraction obtained were tested on neuromuscular preparations of frog and locust and on BLM. A fraction of low molecular weight components (about 5000 daltons and less) was disclosed. This fraction showed presynaptic and channel-forming effects similar to those of crude venoms and of high molecular weight toxin fractions, obtained simultaneously from these venoms. It was shown that channels formed in BLM by crude venoms and its different fractions are identical. Also, it was found that the low molecular weight channel-forming component is a construction element of high molecular weight toxins. On the basis of data obtained a toxin structure model of the Theridiidae family spider venoms was proposed.
P B
PB
Usmanov
I
I
Kazakov
D
D
Kalikulov
B U
BU
Atakuziev
Yukelson LYa
B A
BA
Tashmukhamedov
D000818:Animals; D001180:Arthropod Venoms / Q000494:pharmacology*; D005591:Chemical Fractionation; D004553:Electric Conductivity; D006110:Grasshoppers; D066298:In Vitro Techniques; D007473:Ion Channels / Q000187:drug effects*; D008051:Lipid Bilayers; D009469:Neuromuscular Junction / Q000187:drug effects; D009498:Neurotoxins / Q000494:pharmacology*; D011896:Rana temporaria; D013111:Spider Venoms / Q000494:pharmacology*; D013569:Synapses / Q000187:drug effects
D001180:Arthropod Venoms; D007473:Ion Channels; D008051:Lipid Bilayers; D009498:Neurotoxins; D013111:Spider Venoms