title: Yeast on-target lysis (YOTL), a procedure for making auxiliary mass spectrum data sets for clinical routine identification of yeasts.
abstract: Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS)-based species identification has become a reliable and fast tool for use in clinical diagnostics, including in mycology. To identify yeasts in the MALDI Biotyper system, a multistep extraction protocol, which is also used to generate the reference spectra, is recommended. Sample preparation by on-target lysis (OTL) requires significantly less hands-on time and is therefore highly desirable, but it results in too-low MALDI Biotyper log score values to allow automated species identification. To overcome this problem, we developed a procedure for generating and validating an OTL spectrum data set for the most relevant and frequently occurring yeast species in clinical specimens. The performance was evaluated against a set of OTL spectra derived during clinical routine procedures and from a set of closely related yeasts. In the diagnostic setting, the OTL procedure significantly decreased the workload but allowed species identification with high specificity and sensitivity. False identifications were not observed. The use of in-house-generated OTL reference spectra can highly accelerate MALDI-TOF MS-based yeast species identification using the MALDI Biotyper.
authors.affiliation: Institute for Medical Microbiology, University Medical Center Göttingen, Göttingen, Germany.
authors.forename: Mareike
authors.initials: M
authors.lastname: Bernhard
authors.affiliation: Institute for Medical Microbiology, University Medical Center Göttingen, Göttingen, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Weig
authors.affiliation: Institute for Medical Microbiology, University Medical Center Göttingen, Göttingen, Germany UMG-Laboratory, Institute for Clinical Chemistry, University Medical Center, Göttingen, Germany.
authors.forename: Andreas E
authors.initials: AE
authors.lastname: Zautner
authors.affiliation: Institute for Medical Microbiology, University Medical Center Göttingen, Göttingen, Germany.
authors.forename: Uwe
authors.initials: U
authors.lastname: Groß
authors.affiliation: Institute for Medical Microbiology, University Medical Center Göttingen, Göttingen, Germany obader@gwdg.de.
authors.forename: Oliver
authors.initials: O
authors.lastname: Bader
mesh_terms: D003951:Diagnostic Errors; D006801:Humans; D009181:Mycoses / Q000175:diagnosis*; D012680:Sensitivity and Specificity; D013048:Specimen Handling / Q000379:methods*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods*; D015003:Yeasts / Q000737:chemistry* / Q000145:classification*