title: Extraction and characterization of the insecticidal toxin hirsutellin A produced by Hirsutella thompsonii var. thompsonii.
abstract: Hirsutellin A (HtA) produced by Hirsutella thompsonii var. thompsonii (strain JAB-04) was extracted and purified using a combination of ion-exchange, gel-permeation, and immunoaffinity chromatography. The identity of the purified HtA was confirmed by amino acid analysis and N-terminal sequencing. Monoclonal antibodies prepared against HtA were capable of detecting 25-50 ng of HtA by direct sandwich ELISA. In addition, utilizing Western blot methods, the antibodies were shown to be specific to HtA. The production of HtA was monitored during submerged fermentation. The peak level of exocellular HtA (13-14 micrograms/ml) was during the late exponential growth phase (39-45 h), determined by utilizing a combination of densitometric analysis of the 16.3-kDa bands on SDS-PAGE gels and ELISA. HtA production was directly correlated with mycelial growth. Twenty-one-hour culture filtrates were highly toxic to larvae of the greater wax moth. Pure HtA at a final concentration of 40 pmol was highly toxic to Galleria mellonella larvae.
authors.affiliation: Entomology & Nematology Department, University of Florida, Gainesville 32611, USA.
authors.forename: W Z
authors.initials: WZ
authors.lastname: Liu
authors.forename: D G
authors.initials: DG
authors.lastname: Boucias
authors.forename: C W
authors.initials: CW
authors.lastname: McCoy
mesh_terms: D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D000911:Antibodies, Monoclonal; D002846:Chromatography, Affinity; D002848:Chromatography, DEAE-Cellulose; D002852:Chromatography, Ion Exchange; D004591:Electrophoresis, Polyacrylamide Gel; D005285:Fermentation; D005656:Fungal Proteins / Q000737:chemistry* / Q000302:isolation & purification / Q000633:toxicity; D007814:Larva; D007915:Lepidoptera; D003904:Mitosporic Fungi / Q000254:growth & development*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010446:Peptide Fragments / Q000737:chemistry / Q000302:isolation & purification; D010572:Pest Control, Biological; D017386:Sequence Homology, Amino Acid
chemical_list: D000596:Amino Acids; D000911:Antibodies, Monoclonal; D005656:Fungal Proteins; D010446:Peptide Fragments