title: The potential of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for the identification of biogroups of Cronobacter sakazakii.
abstract: BACKGROUND
  The bacterial genus Cronobacter was established quite recently, in 2008. Therefore, its systematic classification is still in progress as well as the risk assessment of Cronobacter strains. The possibility of rapid identification within the biogroup level has an essential epidemiological significance. We examined the potential of mass spectrometry to accomplish this task on species Cronobacter sakazakii comprising eight different biogroups.
  
  
  METHODS
  Members of all Cronobacter sakazakii biogroups were characterized by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) using intact cells. Analyses were performed on a Biflex IV MALDI-TOF mass spectrometer in the range of 2000 to 20 000 Da in linear mode with an accelerated voltage of 19 kV.
  
  
  RESULTS
  Optimal conditions for a proper identification of biogroups, such as suitable cultivation media or growth time of bacteria, were investigated. The biomarker patterns characterizing each of the Cronobacter sakazakii biogroups were obtained. The established identification protocol was applied to ten previously non-identified strains and their biogroups were successfully determined.
  
  
  CONCLUSIONS
  The presented work is the first report of successful and rapid bacterial biogroup taxonomy classification using MALDI-TOF-MS that could substitute demanding biochemical testing.
authors.affiliation: Department of Biochemistry and Microbiology, Institute of Chemical Technology Prague, Technická 5, 166 28, Prague, Czech Republic.
authors.forename: Ludmila
authors.initials: L
authors.lastname: Karamonová
authors.forename: Petra
authors.initials: P
authors.lastname: Junková
authors.forename: Denisa
authors.initials: D
authors.lastname: Mihalová
authors.forename: Barbora
authors.initials: B
authors.lastname: Javůrková
authors.forename: Ladislav
authors.initials: L
authors.lastname: Fukal
authors.forename: Pavel
authors.initials: P
authors.lastname: Rauch
authors.forename: Martina
authors.initials: M
authors.lastname: Blažková
mesh_terms: D015373:Bacterial Typing Techniques / Q000379:methods*; D015415:Biomarkers / Q000032:analysis / Q000737:chemistry; D016000:Cluster Analysis; D044083:Cronobacter sakazakii / Q000737:chemistry* / Q000145:classification* / Q000254:growth & development; D003470:Culture Media / Q000737:chemistry / Q000378:metabolism; D015203:Reproducibility of Results; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*
chemical_list: D015415:Biomarkers; D003470:Culture Media