title: Matrix assisted laser desorption ionisation time of flight mass spectrometry (MALDI-TOF MS) for detecting novel Bt toxins.
abstract: Matrix assisted laser desorption ionisation time of flight mass spectrometry (MALDI-TOF MS) was used to study crystal (Cry) toxins from different Bacillus thuringiensis (Bt) strains. Known Cry toxins such as Cry1Ac and Cry2A, as well as novel toxins for which the protein sequences were predicted by their gene sequences, were used as controls in this study. The peptide masses, obtained after in-gel trypsin digestion for all these proteins, matched correctly to the corresponding proteins. Also, MALDI-TOF MS was able to resolve and identify multiple Cry toxins of very similar molecular weights and highly similar isoelectric points, from a single protein band. Furthermore, in novel Bt strains for which PCR techniques were unable to detect the cognate genes, this method was able to detect novel Cry toxins. Hence, present data clearly suggest that MALDI-TOF MS could be used as a tool for identifying Cry toxins from novel Bt strains.
authors.affiliation: Division of Entomology, CSIRO, GPO Box 1700, Canberra, ACT 2601, Australia.
authors.forename: Charani
authors.initials: C
authors.lastname: Ranasinghe
authors.forename: Raymond J
authors.initials: RJ
authors.lastname: Akhurst
mesh_terms: D001413:Bacillus thuringiensis; D001427:Bacterial Toxins / Q000032:analysis*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D001427:Bacterial Toxins