title: MALDI-ToF mass spectrometry-multivariate data analysis as a tool for classification of reactivation and non-culturable states of bacteria.
abstract: Some bacterial life states are only difficult to describe and to detect because they are on the border of active metabolism. A prominent example is the so-called viable but non-culturable state, which is mainly characterized by the inability of bacteria to grow on synthetic media. Matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-ToF/MS) in combination with multivariate data analysis represents a powerful tool for mass-spectrometric pattern recognition of biological samples. This method is already used for differentiation of bacterial strains. In this study we present a rapid readout method based on MALDI-ToF/MS in combination with principal component analysis to classify the bacterial non-culturable state using Enterococcus faecalis as a model organism. By applying this technique to samples of different physiological states, distinct clusters were calculated and all mass spectra were classified correctly into groups of similar type concerning their physiological state.
authors.affiliation: Karlsruhe Institute of Technology (KIT), P.O. Box 36 40, 76021 Karlsruhe, Germany. boris.kuehl@kit.edu
authors.forename: Boris
authors.initials: B
authors.lastname: Kuehl
authors.forename: Silke-Mareike
authors.initials: SM
authors.lastname: Marten
authors.forename: Yvonne
authors.initials: Y
authors.lastname: Bischoff
authors.forename: Gerald
authors.initials: G
authors.lastname: Brenner-Weiss
authors.forename: Ursula
authors.initials: U
authors.lastname: Obst
mesh_terms: D001419:Bacteria / Q000166:cytology*; D001431:Bacteriological Techniques / Q000379:methods*; D013293:Enterococcus faecalis / Q000166:cytology; D050296:Microbial Viability; D015999:Multivariate Analysis; D025341:Principal Component Analysis; D011550:Pseudomonas aeruginosa / Q000166:cytology; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*