Structures and biological activities of three synaptic antagonists from orb weaver spider venom

doi:10.1016/0006-291X(87)90930-2

Biochemical and Biophysical Research Communications

Volume 148, Issue 2, 29 October 1987, Pages 678-683

https://doi.org/10.1016/0006-291X(87)90930-2 Get rights and content

Abstract

The venom of Argiope aurantia, an orb weaver spider, contains a mixture of low molecular weight “argiotoxins”, which block neuromuscular transmission in insects. Complete structure elucidation of three argiotoxins reveals common features; a hydrophilic, basic domain of arginine, a polyamine and asparagine is connected to an aromatic moiety contributed either by 4-hydroxyindole-3-acetic acid or 2,4-dihydroxyphenylacetic acid. Structural assignments of two argiotoxins are verified by chemical synthesis. The argiotoxins cause reversible paralysis when injected into insects and this is correlated with a stimulus-dependent inhibition of skeletal neuromuscular transmission at submicromolar concentrations.

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Citation Excerpt :
They block neuromuscular transmission and cause reversible paralysis in insects. Their structures reveal common features and consist of a basic residue of arginine, an acylpolyamine chain, and an asparagine that is connected to an aromatic moiety (Adams et al., 1987). Jackson and Parks (1989) have shown that acylpolyamine toxins with amino acid(s) in their structure have similar modes of action at invertebrate neuromuscular junctions, by exerting noncompetitive blocking of AMPA-sensitive receptors.
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Structures and biological activities of three synaptic antagonists from orb weaver spider venom

Abstract

Trends Neurosci

Brain Res. Rev

Trends Neurosci

Trends Neurosci

Brain Res

Brain Res

J. Mag. Reson

J. Mag. Reson

A. Rev. Pharmac. Toxicol