title: Identification of marker proteins for Bacillus anthracis using MALDI-TOF MS and ion trap MS/MS after direct extraction or electrophoretic separation.
abstract: Direct extraction of bacterial vegetative cells or spores followed by matrix-assisted laser desorption ionization/time of flight mass spectrometry (MALDI TOF MS) has become popular for bacterial identification, since it is simple to perform and mass spectra are readily interpreted. However, only high-abundance proteins that are of low mass and ionize readily are observed. In the case of B. anthracis spores, small acid-soluble spore proteins (SASPs) have been the most widely studied. Additional information can be obtained using tandem mass spectrometry (MS-MS) to confirm the identity of proteins by sequencing. This is most readily accomplished using ion trap (IT) MS-MS. However, enzymatic digestion of these proteins is needed to generate peptides that are within the mass range of the ion trap. The use of sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), or other forms of electrophoresis, allows one to focus on specific proteins of interest (e.g. the high mass exosporium glycoproteins BcIA and BcIB) that provide additional species- and strain-specific discrimination.
authors.affiliation: Department of Pathology & Microbiology, Chemical Engineering, University of South Carolina, Columbia, SC, USA.
authors.forename: Michael J
authors.initials: MJ
authors.lastname: Stump
authors.forename: Gavin
authors.initials: G
authors.lastname: Black
authors.forename: Alvin
authors.initials: A
authors.lastname: Fox
authors.forename: Karen F
authors.initials: KF
authors.lastname: Fox
authors.forename: Charles E
authors.initials: CE
authors.lastname: Turick
authors.forename: Michael
authors.initials: M
authors.lastname: Matthews
mesh_terms: D001408:Bacillus anthracis / Q000145:classification* / Q000302:isolation & purification*; D001426:Bacterial Proteins / Q000032:analysis*; D015415:Biomarkers / Q000032:analysis; D019295:Computational Biology; D013058:Mass Spectrometry / Q000379:methods; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D017550:Spectroscopy, Fourier Transform Infrared
chemical_list: D001426:Bacterial Proteins; D015415:Biomarkers