Abstract
Typhoidal and para-typhoidal Salmonella are major causes of bacteraemia in resource-limited countries. Diagnostic alternatives to laborious and resource-demanding serotyping are essential. Fourier transform infrared spectroscopy (FTIRS) is a rapidly developing and simple bacterial typing technology. In this study, we assessed the discriminatory power of the FTIRS-based IR Biotyper (Bruker Daltonik GmbH, Bremen, Germany), for the rapid and reliable identification of biochemically confirmed typhoid and paratyphoid fever-associated Salmonella isolates. In total, 359 isolates, comprising 30 S. Typhi, 23 S. Paratyphi A, 23 S. Paratyphi B, and 7 S. Paratyphi C, respectively and other phylogenetically closely related Salmonella serovars belonging to the serogroups O:2, O:4, O:7 and O:9 were tested. The strains were derived from clinical, environmental and food samples collected at different European sites. Applying artificial neural networks, specific automated classifiers were built to discriminate typhoidal serovars from non-typhoidal serovars within each of the four serogroups. The accuracy of the classifiers was 99.9%, 87.0%, 99.5% and 99.0% for Salmonella Typhi, Salmonella Paratyphi A, B and Salmonella Paratyphi C, respectively. The IR Biotyper is a promising tool for fast and reliable detection of typhoidal Salmonella. Hence, IR biotyping may serve as a suitable alternative to conventional approaches for surveillance and diagnostic purposes.
Highlights
Salmonella enterica, both typhoidal and nontyphoidal Salmonella are amongst the most important bacteria isolated from patients with bacteraemia in resource-limited countries [1,2,3,4,5]
Fourier transform infrared spectroscopy (FTIRS) has been successfully applied in many studies for the discrimination of bacteria at different taxonomic levels
Due to high genetic diversity, Salmonella enterica represents a promising species to be investigated by FTIRS
Summary
Salmonella enterica, both typhoidal and nontyphoidal Salmonella are amongst the most important bacteria isolated from patients with bacteraemia in resource-limited countries [1,2,3,4,5]. FTIRS has been successfully applied in many studies for the discrimination of bacteria at different taxonomic levels (genera, species, serogroup/type, and even at strain level). Due to high genetic diversity, Salmonella enterica represents a promising species to be investigated by FTIRS. S. enterica serotypes using multivariate analysis and different bacterial collections [53,54,55,56,57,58], but without specific regard to (para-)typhoid Salmonella so far. We evaluated the application of the IR Biotyper (IRBT), an FTIRS commercially available system for microbial typing, for the identification of typhoid and paratyphoid fever-associated Salmonella. The classifiers aimed to discriminate the samples in “Paratyphi (A/B/C)/Typhi”/“non-Paratyphi (A/B/C)/Typhi” These were built with spectra from cultures grown on Columbia Blood agar and were tested with spectra from cultures on different media
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
