ABSTRACT
INTRODUCTION: Currently, Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) is being evaluated for its efficacy as a fast bacterial typing tool due to its great speed compared to other molecular methods. In this study, we evaluated MALDI-TOF as a tool for quick identification and typing of Francisella tularensis. MATERIALS AND METHODS: This study encompassed 86 strains from two different geographical origins (Spain and the Czech Republic), which were previously characterised by Pulsed-Field Gel Electrophoresis (PFGE) and Multiple-Locus Variable Number Tandem Repeat Analysis (MLVA). The direct colony method was used for microbial identification. High-quality spectra of the 86 strains were obtained and their main spectra profiles (MSPs) were created for epidemiological typing using MALDI-TOF. Based on the MSPs, principal components were generated and a dendrogram was constructed. An in-house MALDI-TOF library entry was created for each group of PFGE and MLVA strains based on their high-quality spectra. Two dendrograms were obtained using these entries and the unique peaks in each entry were searched. RESULTS: All strains were correctly identified to the species level. No clear divisions were found in the 86-strain dendrogram; however, Spanish and Czech strains appeared separately in dendrograms created using MLVA and PFGE entries. Entries from our in-house MALDI-TOF library revealed 2-4 biomarker peaks for the detection of the five PFGE groups and 1-12 biomarker peaks for the detection of the seven MLVA groups. Finally, two and one specific biomarkers were found in the Czech and Spanish strains, respectively. CONCLUSION: MALDI-TOF can be used to accurately identify F. tularensis strains in less than 15â¯min. Moreover, data on geographical origin and PFGE and MLVA groups could be obtained in less than one hour after colony growing.
Subject(s)
Bacterial Typing Techniques/methods , Francisella tularensis/isolation & purification , Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization/methods , Tularemia/microbiology , Bacteriological Techniques/methods , Electrophoresis, Gel, Pulsed-Field/methods , Francisella tularensis/classification , Humans , Tularemia/diagnosis , Tularemia/epidemiologyABSTRACT
No disponible
Subject(s)
Humans , Female , Adult , Laboratory Personnel , Fever of Unknown Origin , Tularemia/diagnosis , Tularemia/etiology , Francisella tularensis/isolation & purification , Occupational Diseases/microbiologyABSTRACT
No disponible
Subject(s)
Humans , Empyema, Pleural/microbiology , Lung Diseases, Fungal/diagnosis , Thoracentesis , Antifungal Agents/therapeutic useABSTRACT
No disponible