Isolation and sequencing of insecticidal peptides from the primitive hunting spider, Plectreurys tristis (Simon)

About 50 peptide toxins were purified from venom of the primitive hunting spider, Plectreurys tristis. Bioassay by injection into larval Heliothis virescens (tobacco budworm) allowed selection of nine toxins for analysis of amino acid sequences. Total sequences were determined for six of the more insecticidal peptides (46-49 amino acids) and three contained free carboxyl-terminal amino acids. These toxins (plectoxins) are paralytic and/or lethal when injected into insect pests such as the lepidopterous larvae H. virescens, Spodoptera exigua (beet armyworm), and Manduca sexta (tobacco hornworm). We expect these plectoxins to be useful in insect control after delivery by a suitable agent such as a recombinant baculovirus.