title: Discrimination between wild-type and ampicillin-resistant Escherichia coli by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.
abstract: Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was optimized to discriminate between wild-type and ampicillin-resistant Escherichia coli. Only ampicillin-resistant E. coli displayed an m/z approximately 29,000 peak, which was confirmed as beta-lactamase by in-gel digestion followed by peptide mass fingerprinting. Rapid MALDI-TOF MS detection of antibiotic-resistance could fulfill an important clinical need, providing critical phenotypic information beyond genus-species identification.
authors.affiliation: Analytical Chemistry Division, National Institute of Standards and Technology, 100 Bureau Drive, Gaithersburg, MD 20899, USA. johanna.camara@nist.gov
authors.forename: Johanna E
authors.initials: JE
authors.lastname: Camara
authors.forename: Faith A
authors.initials: FA
authors.lastname: Hays
mesh_terms: D000667:Ampicillin; D004351:Drug Resistance; D004926:Escherichia coli / Q000302:isolation & purification*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D053719:Tandem Mass Spectrometry / Q000379:methods*; D001618:beta-Lactamases / Q000032:analysis
chemical_list: D000667:Ampicillin; D001618:beta-Lactamases