Title
Rapid and reliable discrimination between Shigella species and Escherichia coli using MALDI-TOF mass spectrometry
Author
Paauw, A.
Jonker, D.
Roeselers, G.
Heng, J.M.E.
Mars-Groenendijk, R.H.
Trip, H.
Molhoek, E.M.
Jansen, H.J.
van der Plas, J.
de Jong, A.L.
Majchrzykiewicz-Koehorst, J.A.
Speksnijder, A.G.C.L.
Publication year
2015
Abstract
E. coli-. Shigella species are a cryptic group of bacteria in which the Shigella species are distributed within the phylogenetic tree of E. coli. The nomenclature is historically based and the discrimination of these genera developed as a result of the epidemiological need to identify the cause of shigellosis, a severe disease caused by Shigella species. For these reasons, this incorrect classification of shigellae persists to date, and the ability to rapidly characterize E. coli and Shigella species remains highly desirable. Until recently, existing matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) assays used to identify bacteria could not discriminate between E. coli and Shigella species. Here we present a rapid classification method for the E. coli-. Shigella phylogroup based on MALDI-TOF MS which is supported by genetic analysis. E. coli and Shigella isolates were collected and genetically characterized by MLVA. A custom reference library for MALDI-TOF MS that represents the genetic diversity of E. coli and Shigella strains was developed. Characterization of E. coli and Shigella species is based on an approach with Biotyper software. Using this reference library it was possible to distinguish between Shigella species and E. coli. Of the 180 isolates tested, 94.4% were correctly classified as E. coli or shigellae. The results of four (2.2%) isolates could not be interpreted and six (3.3%) isolates were classified incorrectly. The custom library extends the existing MALDI-TOF MS method for species determination by enabling rapid and accurate discrimination between Shigella species and E. coli. © 2015 Elsevier GmbH.
Subject
Observation, Weapon & Protection Systems
CBRN - CBRN Protection
TS - Technical Sciences
Biology
Bruker
Discrimination
Escherichia coli
MALDI-TOF
Mass spectrometry
Shigella species
Allele
Bacterial strain
Bacterium identification
Bacterium isolate
Computer program
Controlled study
Escherichia coli
Gene sequence
Genetic variability
Human
Matrix assisted laser desorption ionization time of flight mass spectrometry
Multilocus sequence typing
Nonhuman
Nuclear magnetic resonance spectrometer
Serotyping
Shigella
Shigella boydii
Shigella dysenteriae
Shigella flexneri
Shigella sonnei
Species distribution
To reference this document use:
http://resolver.tudelft.nl/uuid:1180c205-d50b-4315-9efc-e50cf3ba05e0
DOI
https://doi.org/10.1016/j.ijmm.2015.04.001
TNO identifier
527776
Publisher
Elsevier
ISSN
1438-4221
Source
International Journal of Medical Microbiology, 305 (4-5), 446-452
Document type
article