Application of MALDI Biotyper System for Rapid Identification of Bacteria Isolated from a Fresh Produce Market
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MALDI-TOF MS has revolutionized the identification of microorganisms and has become an indispensable part of routine diagnostics in the clinical microbiological laboratory. However, application of this technique in microbial surveillance outside of clinical settings is limited. In this study, we have evaluated the performance of a Bruker MALDI Biotyper System for the identification of bacteria isolated from the hand palms of fresh produce handlers and their surrounding environments in a wholesale fresh produce market in Doha, Qatar. The accuracy was verified against the results obtained by bacterial 16S rRNA gene sequencing. A total of 105 isolates were tested, of which 67 (64%) isolates were identified by MALDI-TOF MS and 101 isolates (96%) were identified by 16S rRNA gene sequencing, either at the genus level or species level. However, MALDI-TOF MS identified more isolates (41%) at the species level than 16S rRNA gene sequencing (28%). MALDI-TOF MS was particularly useful in the species level identification of Enterobacteriaceae. MALDI-TOF MS successfully identified most known human pathogens in a rapid and cost-effective manner but failed to identify a significant number of isolates that were of environmental origin, suggesting room for further expansion of the reference database.
This study was partly supported by a GSRA Grant # (GSRA2-1-0615-14038) from the Qatar National Research Fund (a member of Qatar foundation) and Qatar University Student Grant (QUST-CAS-SPR-2017-12). We gratefully acknowledge the technical support from the Microbiology and Pathology Sciences Laboratories of Sidra Medicine and Center for Sustainable Development Laboratory of Qatar University.
Compliance with Ethical Standards
Conflict of interest
The authors declare that they have no conflict of interest.
Produce handler’s hand swab samples were collected as per the protocols approved by Qatar University’s Institutional Review Board (QU-IRB) (No. QU-IRB 509-E/15).
Written informed consent was obtained from all study participants in a form approved by QU-IRB.
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