Application of MALDI-TOF MS for the Identification of Food Borne Bacteria

Matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) has recently emerged as a powerful tool for the routine identification of clinical isolates. MALDI-TOF MS based identification of bacteria has been shown to be more rapid, accurate and cost-efficient than conventional phenotypic techniques or molecular methods. Rapid and reliable identification of food-associated bacteria is also of crucial importance for food processing and product quality. This review is concerned with the applicability of MALDI-TOF MS for routine identification of foodborne bacteria taking the specific requirements of food microbiological laboratories and the food industry into account. The current state of knowledge including recent findings and new approaches are discussed.

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Evaluation of Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry for Rapid Identification of Bacteria in Processed Soybean Products

Journal of Food Research ◽

10.5539/jfr.v2n3p104 ◽

2013 ◽

Vol 2 (3) ◽

pp. 104 ◽

Cited By ~ 2

Author(s):

Yuko Furukawa ◽

Mitsuru Katase ◽

Kazunobu Tsumura

Keyword(s):

Laser Desorption ◽

Rapid Identification ◽

Bacterial Cells ◽

Laser Desorption Ionization ◽

Ionization Time ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Flight Mass Spectrometry ◽

Identification Of Bacteria ◽

Tof Ms

Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has recently been demonstrated as a rapid and reliable method for identifying bacteria in colonies grown on culture plates. Rapid identification of food spoilage bacteria is important for ensuring the quality and safety of food. To shorten the time of analysis, several researchers have proposed the direct MALDI-TOF MS tequnics for identification of bacteria in clinical samples such as urine and positive blood cultures. In this study, processed soybean products (total 26 test samples) were initially conducted a culture enrichiment step and bacterial cells were separated from interfering components. Harvested bacterial cells were determined by MALDI-TOF MS and 16S rRNA gene sequencing method. Six processed soybean products (23%) were increased bacterial cells after culture enrichiment step and they were sucessfully obtained the accurate identification results by MALDI-TOF MS-based method without colony formation.

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Accuracy of conventional identification methods used for Enterobacteriaceae isolates in three Nigerian hospitals

PeerJ ◽

10.7717/peerj.2511 ◽

2016 ◽

Vol 4 ◽

pp. e2511 ◽

Cited By ~ 4

Author(s):

Christiana Jesumirhewe ◽

Peter Oladejo Ogunlowo ◽

Mitsan Olley ◽

Burkhard Springer ◽

Franz Allerberger ◽

...

Keyword(s):

Multidrug Resistant ◽

Species Level ◽

Accurate Identification ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Flight Mass Spectrometry ◽

Maldi Biotyper ◽

Identification Of Bacteria ◽

Identification Techniques ◽

Tof Ms

BackgroundEnterobacteriaceae are ubiquitously present in nature and can be found in the intestinal tract of humans and animals as commensal flora. Multidrug-resistant Enterobacteriaceae are increasingly reported and are a threat to public health implicating a need for accurate identification of the isolates to species level. In developing countries, identification of bacteria basically depends on conventional methods: culture and phenotypic methods that hamper the accurate identification of bacteria. In this study, matrix-assisted desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) technique was compared to conventional identification techniques.Materials and MethodsIn total, 147 Enterobacteriaceae isolates were collected from March to May 2015 from three medical microbiology laboratories of hospitals in Edo state, Nigeria, after being tested according to the individual laboratories standard operating procedures. All isolates were stored at −20°C until tested centrally by MALDI-TOF MS.ResultsOne hundred and forty five (98.6%) isolates had a MALDI Biotyper best score > or =2.0, indicating a secure genus and probable species identification; and 2(1.36%) isolates had a best score <2.0 indicating probable genus identification. Isolates with best scores of > or =2.0 comprised nine genera and 10 species, respectively. A total of 57.2% and 33.1% of isolates identified had agreement between MALDI-TOF MS and conventional techniques for identification at genus and species level, respectively, when analyzing bacteria with MALDI Biotyper best scores > or =2.0.ConclusionThe results of our study show that the applied conventional identification techniques for Enterobacteriaceae in the investigated Nigerian hospitals are not very accurate. Use of state-of-the-art identification technologies for microorganisms is necessary to guarantee comparability of bacteriological results.

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A Moldy Application of MALDI: MALDI-ToF Mass Spectrometry for Fungal Identification

Journal of Fungi ◽

10.3390/jof5010004 ◽

2019 ◽

Vol 5 (1) ◽

pp. 4 ◽

Cited By ~ 23

Author(s):

Robin Patel

Keyword(s):

Mass Spectrometry ◽

Filamentous Fungi ◽

Bacterial Identification ◽

Ionization Time ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Flight Mass Spectrometry ◽

Fungal Identification ◽

Routine Identification ◽

Tof Ms

As a result of its being inexpensive, easy to perform, fast and accurate, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-ToF MS) is quickly becoming the standard means of bacterial identification from cultures in clinical microbiology laboratories. Its adoption for routine identification of yeasts and even dimorphic and filamentous fungi in cultures, while slower, is now being realized, with many of the same benefits as have been recognized on the bacterial side. In this review, the use of MALDI-ToF MS for identification of yeasts, and dimorphic and filamentous fungi grown in culture will be reviewed, with strengths and limitations addressed.

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Intact Staphylococcus Enterotoxin SEB from Culture Supernatant Detected by MALDI-TOF Mass Spectrometry

Toxins ◽

10.3390/toxins11020101 ◽

2019 ◽

Vol 11 (2) ◽

pp. 101 ◽

Cited By ~ 4

Author(s):

Jenna Tonacini ◽

Dario Stephan ◽

Guido Vogel ◽

Marc-André Avondet ◽

Franka Kalman ◽

...

Keyword(s):

Mass Spectrometry ◽

Culture Supernatant ◽

Main Peak ◽

Amino Acid Sequence Analysis ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Flight Mass Spectrometry ◽

Routine Identification ◽

Intracellular Proteins ◽

Tof Ms

Routine identification of pathogens by MALDI-TOF MS (matrix-assisted laser desorption ionisation time-of-flight mass spectrometry) is based on the fingerprint of intracellular proteins. This work evaluated the use of MALDI-TOF MS for the identification of extracellular pathogen factors. A Staphylococcus aureus isolate from a food contaminant was exponentially grown in liquid cultures. Secreted proteins were collected using methanol– chloroform precipitation and analysed by MALDI-TOF MS. A main peak m/z 28,250 was demonstrated, which was identified as S.aureus enterotoxin type B (SEB) by using the pure authentic SEB reference of 28.2 kDa and by amino acid sequence analysis. SEB was also detected in this intact form following pasteurization and cooking treatments. Further application of the elaborated MALDI-TOF MS protocol resulted in the detection of SEA at m/z 27,032 and SEC at m/z 27,629. In conclusion, a simple sample preparation from S.aureus cultures and an easy-to-perform identification of pathogen factors SE in intact form represents a promising next-generation application of MALDI-TOF MS.

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MALDI-TOF MS in clinical parasitology: applications, constraints and prospects

Parasitology ◽

10.1017/s0031182016001189 ◽

2016 ◽

Vol 143 (12) ◽

pp. 1491-1500 ◽

Cited By ~ 17

Author(s):

NEELJA SINGHAL ◽

MANISH KUMAR ◽

JUGSHARAN SINGH VIRDI

Keyword(s):

Laser Desorption ◽

Laser Desorption Ionization ◽

Ionization Time ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Flight Mass Spectrometry ◽

Identification Of Bacteria ◽

Tof Ms ◽

Matrix Assisted Laser ◽

Matrix Assisted Laser Desorption

SUMMARYMatrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) is currently being used for rapid and reproducible identification of bacteria, viruses and fungi in clinical microbiological laboratories. However, some studies have also reported the use of MALDI-TOF MS for identification of parasites, likeLeishmania, Giardia, Cryptosporidium, Entamoeba, ticks and fleas. The present review collates all the information available on the use of this technique for parasites, in an effort to assess its applicability and the constraints for identification/diagnosis of parasites and diseases caused by them. Though MALDI-TOF MS-based identification of parasites is currently done by reference laboratories only, in future, this promising technology might surely replace/augment molecular methods in clinical parasitology laboratories.

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MALDI-TOF MS Andromas strategy for the routine identification of bacteria, mycobacteria, yeasts, Aspergillus spp. and positive blood cultures

Clinical Microbiology and Infection ◽

10.1111/j.1469-0691.2011.03688.x ◽

2012 ◽

Vol 18 (11) ◽

pp. 1117-1125 ◽

Cited By ~ 93

Author(s):

E. Bille ◽

B. Dauphin ◽

J. Leto ◽

M.-E. Bougnoux ◽

J.-L. Beretti ◽

...

Keyword(s):

Blood Cultures ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Routine Identification ◽

Identification Of Bacteria ◽

Tof Ms

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Test Agreement among Biochemical Methods, Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry, and 16S rRNA Sequencing for Identification of Microorganisms Isolated from Bovine Milk

Journal of Clinical Microbiology ◽

10.1128/jcm.01381-18 ◽

2018 ◽

Vol 57 (3) ◽

Cited By ~ 2

Author(s):

David J. Wilson ◽

John R. Middleton ◽

Pamela R. F. Adkins ◽

Gregory M. Goodell

Keyword(s):

16S Rrna ◽

Species Level ◽

Content Type ◽

Maldi Tof Ms ◽

Milk Samples ◽

Maldi Tof ◽

Flight Mass Spectrometry ◽

Identification Of Bacteria ◽

Biochemical Testing ◽

Tof Ms

ABSTRACT The objective of this prospective study was a blinded comparison of three methods for the identification of bacteria isolated on Columbia blood agar from milk samples of dairy cows. Basic biochemical testing, matrix-assisted laser desorption ionization–time of flight mass spectrometry (MALDI-TOF MS), and 16S rRNA partial genome sequence analysis were compared for bacterial identification to the genus or species level. Milk samples submitted from a commercial dairy farm from recently calved cows or clinical mastitis cases were cultured, and 181 isolates were identified by biochemical testing, MALDI-TOF MS, and 16S rRNA sequence analysis (179 isolates; 2 isolates could not be recovered from storage). For Staphylococcus aureus and Escherichia coli, agreement was determined at the species level. For other microbes, agreement was determined at the genus level or at the group level for streptococcus-like organisms. The positive agreement among all 3 diagnostic methods was 94%, with 95% to 98% between each pair of methods. The overall (including negative agreement) agreement among all 3 methods ranged from 97% to 100%. MALDI-TOF MS is becoming more commonplace for the genus- and/or species-level identification of bacteria isolated from milk samples and, in some laboratories, has replaced conventional biochemical methods. The results of the present study suggest that when identifying pathogens at the genus or group level, conventional culture followed up with either secondary biochemical testing or MALDI-TOF MS is of practical value. For purposes of milk quality and udder health monitoring or research, any of the 3 methods is a valuable tool for genus-level identification of bacteria isolated from dairy cow milk.

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MALDI-TOF MS – application in food microbiology

Acta Biochimica Polonica ◽

10.18388/abp.2020_5380 ◽

2020 ◽

Author(s):

Monika Akimowicz ◽

Joanna Bucka-Kolendo

Keyword(s):

Food Industry ◽

Food Products ◽

Food Microbiology ◽

Spectroscopic Techniques ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Flight Mass Spectrometry ◽

Contaminated Food ◽

Cost Efficient ◽

Tof Ms

Microbiological purity control of food products is of great importance in the food industry. Contaminated food is often characterized by a deteriorated taste, smell, and appearance, and when consumed, it can pose a threat to human health and life. Also, contamination incurs huge financial losses to the food industry. Different methods are used for identification of the microorganisms isolated from food, which are based on phenotypic, immunologic, genetic, and spectroscopic techniques. Unfortunately, these methods have the following disadvantages: laborious, time-consuming, requiring a well-trained spectrometer operator with specialist knowledge, or very accurate, but complicated, and extremely expensive. In recent years, matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) has been gaining increasing importance in the field of food microbiology. Unlike other techniques used for microorganisms identification, MALDI-TOF MS is more rapid, accurate and cost-efficient, and easy to perform. Thus, this method can be applied in the food industry to quickly and accurately identify microorganisms, which is crucial for controlling the quality of food products. The present review aims to discuss the selected applications of MALDI-TOF MS in food microbiology. It mainly focuses on the characteristics of this method and its potential use in the identification and typing of microorganisms including filamentous fungi, yeasts, and bacteria in fermented beverages (beer and wine), honey, dairy products like yogurt and pasteurized milk, pork, and seafood.

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Rapid Identification and Typing of Listeria Species by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry

Applied and Environmental Microbiology ◽

10.1128/aem.02689-07 ◽

2008 ◽

Vol 74 (17) ◽

pp. 5402-5407 ◽

Cited By ~ 225

Author(s):

Sukhadeo B. Barbuddhe ◽

Thomas Maier ◽

Gerold Schwarz ◽

Markus Kostrzewa ◽

Herbert Hof ◽

...

Keyword(s):

Laser Desorption ◽

Laser Desorption Ionization ◽

Ionization Time ◽

Maldi Tof Ms ◽

Maldi Tof ◽

Flight Mass Spectrometry ◽

Food Borne ◽

Tof Ms ◽

Matrix Assisted Laser ◽

Matrix Assisted Laser Desorption

ABSTRACT Listeria monocytogenes is a food-borne pathogen that is the causative agent of human listeriosis, an opportunistic infection that primarily infects pregnant women and immunologically compromised individuals. Rapid, accurate discrimination between Listeria strains is essential for appropriate therapeutic management and timely intervention for infection control. A rapid method involving matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) that shows promise for identification of Listeria species and typing and even allows for differentiation at the level of clonal lineages among pathogenic strains of L. monocytogenes is presented. A total of 146 strains of different Listeria species and serotypes as well as clinical isolates were analyzed. The method was compared with the pulsed-field gel electrophoresis analysis of 48 Listeria strains comprising L. monocytogenes strains isolated from food-borne epidemics and sporadic cases, isolates representing different serotypes, and a number of Listeria strains whose genomes have been completely sequenced. Following a short inactivation/extraction procedure, cell material from a bacterial colony was deposited on a sample target, dried, overlaid with a matrix necessary for the MALDI process, and analyzed by MALDI-TOF MS. This technique examines the chemistry of major proteins, yielding profile spectra consisting of a series of peaks, a characteristic “fingerprint” mainly derived from ribosomal proteins. Specimens can be prepared in a few minutes from plate or liquid cultures, and a spectrum can be obtained within 1 minute. Mass spectra derived from Listeria isolates showed characteristic peaks, conserved at both the species and lineage levels. MALDI-TOF MS fingerprinting may have potential for Listeria identification and subtyping and may improve infection control measures.

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