title: Establishing drug resistance in microorganisms by mass spectrometry.
abstract: A rapid method to determine drug resistance in bacteria based on mass spectrometry is presented. In it, a mass spectrum of an intact microorganism grown in drug-containing stable isotope-labeled media is compared with a mass spectrum of the intact microorganism grown in non-labeled media without the drug present. Drug resistance is determined by predicting characteristic mass shifts of one or more microorganism biomarkers using bioinformatics algorithms. Observing such characteristic mass shifts indicates that the microorganism is viable even in the presence of the drug, thus incorporating the isotopic label into characteristic biomarker molecules. The performance of the method is illustrated on the example of intact E. coli, grown in control (unlabeled) and (13)C-labeled media, and analyzed by MALDI TOF MS. Algorithms for data analysis are presented as well.
authors.affiliation: Johns Hopkins University Applied Physics Laboratory, 11100 Johns Hopkins Rd., Laurel, MD 20723, USA. plamen.demirev@jhuapl.edu
authors.forename: Plamen A
authors.initials: PA
authors.lastname: Demirev
authors.forename: Nathan S
authors.initials: NS
authors.lastname: Hagan
authors.forename: Miquel D
authors.initials: MD
authors.lastname: Antoine
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Lin
authors.forename: Andrew B
authors.initials: AB
authors.lastname: Feldman
mesh_terms: D000465:Algorithms; D001408:Bacillus anthracis / Q000737:chemistry / Q000187:drug effects; D019295:Computational Biology; D003627:Data Interpretation, Statistical; D030541:Databases, Genetic; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D004926:Escherichia coli / Q000187:drug effects* / Q000235:genetics*; D023281:Genomics; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D013171:Spores, Bacterial / Q000737:chemistry