Nano-liquid chromatography with tandem mass spectrometry (nLC-MSMS) nLC-MS/MS with Collision Induced Dissociation (CID) was performed on a linear trap quadrupole fourier transform (LTQ FT, Thermo Fisher, Waltham, MA) integrated with an Eksigent nano-LC. A prepacked reverse-phase
column (Microtech Scientific C18 with a dimension of 100 μm x 3.5 cm) containing resin (Biobasic C18, 5-μm particle size, 300-Å pore size, Microtech Scientific, Fontana, CA) was used for peptide chromatography and subsequent CID analyses. ESI conditions using the nano-spray source (Thermo Fisher) for the LTQ-FT were set as follows: capillary temperature of 220°C, tube lens 110 V, and a spray voltage of 2.5 kV. The flow rate for reverse-phase chromatography was 5 μl/min for loading and 300 nl/min for the analytical separation (buffer A: 0.1% formic acid, 1% acetonitrile; buffer B: 0.1% formic acid, Ceritinib purchase HM781-36B cost 100% acetonitrile). Peptides were resolved by the following gradient: 2–60% buffer B over 40 min, then increased to 80% buffer B over 10 min and then returned to 0% buffer B for equilibration of 10 min. The LTQ FT was operated in data-dependent mode with a full precursor scan at high-resolution (100000 at m/z 400) and six MSMS experiments at low resolution on the linear trap while the full scan was completed. For CID the intensity threshold was set to 5000, where mass range was 350–2000. Spectra
were searched using Mascot software not (Matrix Science, UK) in which results with p < 0.05 (95% confidence interval) were considered
significant and indicating identity. The data was also analyzed through Sequest database search algorithm implemented in Discoverer software (Thermo Fisher, Waltham, MA). Identification of the core, non-core, and pan-genome of Bordetella “”Core”" regions were defined as genome sequences that were present in all 11 Bordetella genomes, while “”non-core”" regions were defined as genome sequences that are not present in all genomes. RB50 was used as the reference genome. For each of the other 10 sequences, genomes were mapped to the reference genome using Nucmer [27]. All 10 “.coords” output files from the Nucmer program were analyzed to identify overlap regions based on RB50 coordinates using a Perl script. Finally, “core” sequences were extracted based on the genome sequence of RB50 with the coordinates calculated above. Unshared regions were then added to the reference genome to make a “revised” reference genome, which contained the original sequence plus unshared sequences. This process was repeated until all of the genomes were compared to include all unshared sequences included in the pan-genome. The core region was subtracted from the pan-genome of all the 11 genomes, and the remaining regions were identified as non-core regions. Hierarchical clustering using Cluster and Java Tree View 844 non-core fragments with more than 1000 bp were identified.