title: Characterization and identification of clinically relevant microorganisms using rapid evaporative ionization mass spectrometry.
abstract: Rapid evaporative ionization mass spectrometry (REIMS) was investigated for its suitability as a general identification system for bacteria and fungi. Strains of 28 clinically relevant bacterial species were analyzed in negative ion mode, and corresponding data was subjected to unsupervised and supervised multivariate statistical analyses. The created supervised model yielded correct cross-validation results of 95.9%, 97.8%, and 100% on species, genus, and Gram-stain level, respectively. These results were not affected by the resolution of the mass spectral data. Blind identification tests were performed for strains cultured on different culture media and analyzed using different instrumental platforms which led to 97.8-100% correct identification. Seven different Escherichia coli strains were subjected to different culture conditions and were distinguishable with 88% accuracy. In addition, the technique proved suitable to distinguish five pathogenic Candida species with 98.8% accuracy without any further modification to the experimental workflow. These results prove that REIMS is sufficiently specific to serve as a culture condition-independent tool for the identification and characterization of microorganisms.
authors.affiliation: Section of Computational and Systems Medicine, Department of Surgery and Cancer, Imperial College London , London SW7 2AZ, United Kingdom.
authors.forename: Nicole
authors.initials: N
authors.lastname: Strittmatter
authors.forename: Monica
authors.initials: M
authors.lastname: Rebec
authors.forename: Emrys A
authors.initials: EA
authors.lastname: Jones
authors.forename: Ottmar
authors.initials: O
authors.lastname: Golf
authors.forename: Alireza
authors.initials: A
authors.lastname: Abdolrasouli
authors.forename: Julia
authors.initials: J
authors.lastname: Balog
authors.forename: Volker
authors.initials: V
authors.lastname: Behrends
authors.forename: Kirill A
authors.initials: KA
authors.lastname: Veselkov
authors.forename: Zoltan
authors.initials: Z
authors.lastname: Takats
mesh_terms: D000336:Aerosols / Q000737:chemistry; D001419:Bacteria / Q000737:chemistry* / Q000145:classification; D001424:Bacterial Infections / Q000382:microbiology*; D002177:Candidiasis / Q000382:microbiology*; D006801:Humans; D013058:Mass Spectrometry / Q000191:economics / Q000295:instrumentation*; D013997:Time Factors; D014835:Volatilization; D015003:Yeasts / Q000737:chemistry* / Q000145:classification
chemical_list: D000336:Aerosols