Yoshio Aramaki

Synthesis of spider toxin (JSTX-3) and its analogs

Abstract One of the active principles isolated from spider venom, JSTX-3, and its analogs of the polyamine part were synthesized.

Synthesis of a new neurotoxin NSTX-3 of Papua New Guinean spider

Abstract A new spider toxin NSTX-3 was chemically synthesized for confirmation of the proposed structure and use in the investigation of neuroscience.

Newly synthesized analogues of the spider toxin block the crustacean glutamate receptor

Effects of synthetic compounds similar to the structure of a spider toxin were studied on the glutamate receptors in crustacean neuromuscular synapses. Two kinds of analogues, 2,4-dihydroxyphenylacetyl-asparaginyl cadaverine (C-1) and 2,4-dihydroxyphenylacetyl-asparaginyl spermine (C-2), suppressed the excitatory postsynaptic potentials in a manner similar to natural spider toxin (JSTX). The dose-response relationship showed that the relative potency of the compounds is C-1 less than C-2 less than JSTX. While the effect of JSTX was irreversible, those of C-1 and C-2 were reversible. These synthetic compounds may serve as important tools in studying the structure and function of glutamate receptors.

Total synthesis of nstx-3, spider toxin of nephila maculata

Abstract A spider toxin NSTX-3 obtained from the venom of Papua New Guinean spider, Nephila maculata was synthesized in order to confirm its proposed structure and to supply the sample for the biological tests. The structure of NSTX-3 is now established as 2,4-dihydroxyphenylacetyl-L-Asn→Cad←Pua←L-Arg, where Cad stands for cadaverine and Pua for putreanine.