Example 4
All insecticidal proteins were fractionated and enriched as described. For identification candidate protein bands were excised, digested with trypsin and analyzed by nano-liquid chromatography/electrospray tandem mass spectrometry (nano-LC/ESI-MS/MS) on a Thermo Q Exactive™ Orbitrap™ mass spectrometer (Thermo Fisher Scientific) interfaced with an Eksigent® NanoLC-1D™ Plus nanoLC™ system (AB Sciex). Ten product ion spectra were collected in an information dependent acquisition mode after a MS1 survey scan.
Protein identification was done by database searches using Mascot (Matrix Science). The searches were done against the in-house database Bacteria-Plus, which combines all bacterial protein sequences and keratin sequences derived from the NCBI non-redundant database (nr) as well as in-house protein sequences.