title: Characterisation and profiling of Bacillus subtilis, Bacillus cereus and Bacillus licheniformis by MALDI-TOF mass fingerprinting.
abstract: The Bacillus genus includes species such as Bacillus cereus, Bacillus licheniformis and Bacillus subtilis, some of which may be pathogenic or causative agents in the spoilage of food products. The main goal of this work was to apply matrix-assisted laser desorption ionisation-time of flight (MALDI-TOF) mass fingerprinting to the classification of these Bacillus species. Genetic analyses were also compared to phyloproteomic analyses. A collection of 57 Bacillus strains isolated from fresh and processed food and from culture collections were studied and their mass spectra compiled. The resulting mass fingerprints were compared and characteristic peaks at the strain and species levels were assigned. The results showed that MALDI-TOF was a good complementary approach to 16S rRNA sequencing and even a more powerful tool in the accurate classification of Bacillus species, especially for differentiating B. subtilis and B. cereus from Bacillus amyloliquefaciens and Bacillus thuringiensis, respectively. MALDI-TOF was also found to provide valuable information at both intra- and interspecies levels in the Bacillus species studied.
authors.affiliation: Department of Analytical Chemistry, Nutrition and Food Science, School of Veterinary Sciences/College of Biotechnology, University of Santiago de Compostela, Rúa Carballo Calero s/n, Campus Lugo, E-27002 Lugo, Spain.
authors.forename: I C
authors.initials: IC
authors.lastname: Fernández-No
authors.forename: K
authors.initials: K
authors.lastname: Böhme
authors.forename: M
authors.initials: M
authors.lastname: Díaz-Bao
authors.forename: A
authors.initials: A
authors.lastname: Cepeda
authors.forename: J
authors.initials: J
authors.lastname: Barros-Velázquez
authors.forename: P
authors.initials: P
authors.lastname: Calo-Mata
mesh_terms: D001407:Bacillus / Q000737:chemistry* / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D001409:Bacillus cereus / Q000737:chemistry* / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D001412:Bacillus subtilis / Q000737:chemistry* / Q000145:classification / Q000235:genetics / Q000302:isolation & purification; D015373:Bacterial Typing Techniques / Q000379:methods*; D005516:Food Microbiology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*