title: Recombinant conotoxin, TxVIA, produced in yeast has insecticidal activity.
abstract: Conotoxins are a diverse collection of more than 50,000 peptides produced by predatory marine snails of the genus Conus in order to immobilize their prey. Many conotoxins modulate the activity of ion channels, and show high specificity to their targets; as a result, some have valuable pharmaceutical applications. However, obtaining active peptide is difficult and to date has only been achieved though natural collection, chemical synthesis, or the use of prokaryotic expression systems, which often have the disadvantage of requiring subsequent steps to correctly fold the peptide. This paper reports the production of a conotoxin, TxVIA from Conus textile, as a biologically active recombinant protein, using the yeast Pichia pastoris as expression host. The presence of the pro-peptide was found to be necessary for the expression of biologically active conotoxin. We also show that TxVIA is not, as previously reported, mollusc-specific, but also shows insecticidal activity when injected into lepidopteran (cabbage moth) and dipteran (house fly) larvae. In contrast, recombinant TxVIA was not found to be molluscicidal to the grey field slug Deroceras reticulatum.
authors.affiliation: School of Biological and Biomedical Sciences, Durham University, South Road, Durham DH13LE, UK.
authors.forename: C
authors.initials: C
authors.lastname: Bruce
authors.forename: E C
authors.initials: EC
authors.lastname: Fitches
authors.forename: N
authors.initials: N
authors.lastname: Chougule
authors.forename: H A
authors.initials: HA
authors.lastname: Bell
authors.forename: J A
authors.initials: JA
authors.lastname: Gatehouse
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D020916:Conotoxins / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D052078:Conus Snail / Q000235:genetics*; D004175:Diptera; D004926:Escherichia coli / Q000235:genetics; D049851:Gastropoda / Q000187:drug effects; D007306:Insecticides / Q000378:metabolism* / Q000494:pharmacology; D007814:Larva; D008969:Molecular Sequence Data; D009036:Moths; D030781:Organisms, Genetically Modified / Q000378:metabolism; D010571:Pest Control; D010843:Pichia / Q000235:genetics*; D011993:Recombinant Fusion Proteins / Q000378:metabolism*
chemical_list: D020916:Conotoxins; D007306:Insecticides; D011993:Recombinant Fusion Proteins; C085582:conotoxin TxVIA