Matrix-assisted laser desorption ionization-time of flight mass spectrometry for the identification of clinically relevant bacteria

• Published in: PloS one Vol. 6; no. 1; p. e16424
• Main Authors: Benagli, Cinzia, Rossi, Viviana, Dolina, Marisa, Tonolla, Mauro, Petrini, Orlando
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 25.01.2011; Public Library of Science (PLoS)
• Subjects: Bacteria; Bacteria - isolation & purification; Biology; Candida albicans; Deoxyribonucleic acid; Desorption; Diagnostic tests; DNA; DNA sequencing; E coli; Efficiency; Enterococcus; Enterococcus - isolation & purification; Escherichia coli; Gardnerella; Gardnerella - isolation & purification; Gene sequencing; Identification; Ionization; Ions; Laboratories; Lasers; Mass spectrometry; Mass spectroscopy; Medicine; Methods; Microorganisms; Nucleotide sequence; Pathogens; Proteomics; RNA, Ribosomal, 16S; Scientific imaging; Sequence Analysis; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization - methods; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization - standards; Spectroscopy; Staphylococcus; Staphylococcus - isolation & purification; Staphylococcus aureus; Staphylococcus epidermidis; Staphylococcus infections; Strains (organisms); Streptococcus; Streptococcus - isolation & purification; Streptococcus agalactiae; Streptococcus infections; Studies
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0016424

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) allows rapid and reliable identification of microorganisms, particularly clinically important pathogens. We compared the identification efficiency of MALDI-TOF MS with that of Phoenix®, API® and 16S ribosomal DNA sequence analysis on 1,019 strains obtained from routine diagnostics. Further, we determined the agreement of MALDI-TOF MS identifications as compared to 16S gene sequencing for additional 545 strains belonging to species of Enterococcus, Gardnerella, Staphylococcus, and Streptococcus. For 94.7% of the isolates MALDI-TOF MS results were identical with those obtained with conventional systems. 16S sequencing confirmed MALDI-TOF MS identification in 63% of the discordant results. Agreement of identification of Gardnerella, Enterococcus, Streptococcus and Staphylococcus species between MALDI-TOF MS and traditional method was high (Crohn's kappa values: 0.9 to 0.93). MALDI-TOF MS represents a rapid, reliable and cost-effective identification technique for clinically relevant bacteria.