title: The discriminatory power of MALDI-TOF mass spectrometry to differentiate between isogenic teicoplanin-susceptible and teicoplanin-resistant strains of methicillin-resistant Staphylococcus aureus.
abstract: To explore the discriminatory power of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) for detecting subtle differences in isogenic isolates, we tested isogenic strains of Staphylococcus aureus differing in their expression of resistance to methicillin or teicoplanin. More important changes in MALDI-TOF MS spectra were found with strains differing in methicillin than in teicoplanin resistance. In comparison, very minor or no changes were recorded in pulsed-field gel electrophoresis profiles or peptidoglycan muropeptide digest patterns of these strains, respectively. MALDI-TOF MS might be useful to detect subtle strain-specific differences in ionizable components released from bacterial surfaces and not from their peptidoglycan network.
authors.affiliation: Department of Fundamental Microbiology, University of Lausanne, Lausanne, Switzerland. Paul.Majcherczyk@unil.ch
authors.forename: Paul A
authors.initials: PA
authors.lastname: Majcherczyk
authors.forename: Therese
authors.initials: T
authors.lastname: McKenna
authors.forename: Philippe
authors.initials: P
authors.lastname: Moreillon
authors.forename: Pierre
authors.initials: P
authors.lastname: Vaudaux
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015373:Bacterial Typing Techniques / Q000379:methods; D024881:Drug Resistance, Bacterial; D016521:Electrophoresis, Gel, Pulsed-Field; D006801:Humans; D016106:Methicillin Resistance; D009113:Muramidase / Q000378:metabolism; D010455:Peptides / Q000032:analysis; D010457:Peptidoglycan / Q000737:chemistry / Q000378:metabolism; D012680:Sensitivity and Specificity; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D013211:Staphylococcus aureus / Q000737:chemistry / Q000145:classification* / Q000187:drug effects / Q000235:genetics; D017334:Teicoplanin / Q000494:pharmacology*
chemical_list: D000900:Anti-Bacterial Agents; D010455:Peptides; D010457:Peptidoglycan; D017334:Teicoplanin; D009113:Muramidase