2019 ; Vol.29-4: 548~557
|Author||Eiseul Kim, Hyun-Joong Kim, Seung-Min Yang, Chang-Gyeom Kim, Dong-Won Choo, Hae-Yeong Kim|
|Place of duty||Institute of Life Sciences & Resources and Department of Food Science and Biotechnology, Kyung Hee University, Korea|
|Title||Rapid Identification of Staphylococcus Species Isolated from Food Samples by Matrix-Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry|
J. Microbiol. Biotechnol.2019 ;
|Abstract||Staphylococcus species have a ubiquitous habitat in a wide range of foods, thus the ability to
identify staphylococci at the species level is critical in the food industry. In this study, we
performed rapid identification of Staphylococcus species using Matrix-Assisted Laser
Desorption/Ionization Time-of-Flight mass spectrometry (MALDI-TOF MS). MALDI-TOF MS
was evaluated for the identification of Staphylococcus reference strains (n = 19) and isolates
(n = 96) from various foods with consideration for the impact of sample preparation methods
and incubation period. Additionally, the spectra of isolated Staphylococcus strains were
analyzed using principal component analysis (PCA) and a main spectra profile (MSP)-based
dendrogram. MALDI-TOF MS accurately identified Staphylococcus reference strains and
isolated strains: the highest performance was by the EX method (83.3~89.5% accuracy) at
species level identification (EDT, 70.3~78.9% accuracy; DT, less than 46.3~63.2% accuracy) of
24-h cultured colonies. Identification results at the genus level were 100% accurate at EDT, EX
sample preparation and 24-h incubation time. On the other hand, the DT method showed
relatively low identification accuracy in all extraction methods and incubation times. The
analyzed spectra and MSP-based dendrogram showed that the isolated Staphylococcus strains
were characterized at the species level. The performance analysis of MALDI-TOF MS shows
the method has the potential ability to discriminate between Staphylococcus species from foods
in Korea. This study provides valuable information that MALDI-TOF MS can be applied to
monitor microbial populations and pathogenic bacteria in the food industry thereby
contributing to food safety.|
|Key_word||MALDI-TOF MS, Staphylococcus, jeotgal, fermented food, identification, extraction method|
Becker K, Heilmann C, Peters G. 2014. Coagulase-negative staphylococci. Clin. Microbiol. Rev. 27: 870-926.
Zell C, Resch M, Rosenstein R, Albrecht T, Hertel C, Götz F. 2008. Characterization of toxin production of coagulasenegative staphylococci isolated from food and starter cultures. Int. J. Food Microbiol. 127: 246-251.
Podkowik M, Park JY, Seo KS, Bystroń J, Bania J. 2013. Enterotoxigenic potential of coagulase-negative staphylococci. Int. J. Food Microbiol. 163: 34-40.
Irlinger F. 2008. Safety assessment of dairy microorganisms:coagulase-negative staphylococci. Int. J. Food Microbiol. 126:302-310.
Chajęcka-Wierzchowska W, Zadernowska A, Nalepa B, Sierpinska M, Łaniewska-Trokenheim Ł. 2015. Coagulasenegative staphylococci (CoNS) isolated from ready-to-eat food of animal origin - phenotypic and genotypic antibiotic resistance. Food Microbiol. 46: 222-226.
Ayeni FA, Andersen C, Nørskov-Lauritsen N. 2017. Comparison of growth on mannitol salt agar, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, VITEK 2 with partial sequencing of 16S rRNA gene for identification of coagulase-negative staphylococci. Microb. Pathog. 105: 255-259.
Hwang SM, Kim MS, Park KU, Song J, Kim EC. 2011. Tuf gene sequence analysis has greater discriminatory power than 16S rRNA sequence analysis in identification of clinical isolates of coagulase-negative staphylococci. J. Clin. Microbiol.49: 4142-4149.
Bergeron M, Dauwalder O, Gouy M, Freydiere AM, Bes M, Meugnier H, et al. 2011. Species identification of staphylococci by amplification and sequencing of the tuf gene compared to the gap gene and by matrix-assisted laser desorption ionization time-of-flight mass spectrometry. Eur. J. Clin. Microbiol. Infect. Dis. 30: 343-354.
Drancourt M1, Raoult D. 2002. rpoB gene sequence-based identification of Staphylococcus species. J. Clin. Microbiol. 40:1333-1338.
Rahi P, Prakash O, Shouche YS. 2016. Matrix-assisted laser desorption/ionization time-of-flight mass-spectrometry (MALDI-TOF MS) based microbial identifications: challenges and scopes for microbial ecologists. Front. Microbiol. 30: 1359.
Cho Y, Kim E, Lee Y, Han SK, Choo DW, Kim YR, et al. 2017. Rapid and accurate identification of Pediococcus species isolated from Korean fermented foods by MALDI-TOF MS with local database extension. Int. J. Syst. Evol. Microbiol. 67:744-752.
Kim E, Cho Y, Lee Y, Han SK, Kim CG, Choo DW, et al. 2017. A proteomic approach for rapid identification of Weissella species isolated from Korean fermented foods on MALDI-TOF MS supplemented with an in-house database. Int. J. Food Microbiol. 243: 9-15.
Ahmadsah LSF, Kim E, Jung YS, Kim HY. 2018. Identification by PCR-DGGE, SDS-PAGE, and MALDI-TOF MS of LAB and fungi in laru, a fermented starter. J. Microbiol. Biotechnol.28: 32-39.
Lee Y, Cho Y, Kim E, Kim HJ, Kim HY. 2018. Identification of lactic acid bacteria in Galchi- and Myeolchi-jeotgal by 16S rRNA gene sequencing, MALDI-TOF mass spectrometry, and PCR-DGGE. J. Microbiol. Biotechnol. 28: 1112-1121.
Cameron M, Barkema HW, De Buck J, De Vliegher S, Chaffer M, Lewis J, et al. 2017. Identification of bovineassociated coagulase-negative staphylococci by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry using a direct transfer protocol. J. Dairy Sci. 100: 2137-2147.
Zhu W, Sieradzki K, Albrecht V, McAllister S, Lin W, Stuchlik O, et al. 2015. Evaluation of the Biotyper MALDITOF MS system for identification of Staphylococcus species. J. Microbiol. Methods 117: 14-17.
Freiwald A, Sauer S. 2009. Phylogenetic classification and identification of bacteria by mass spectrometry. Nature Protoc. 4: 732-742.
Cho Y, Kim E, Han SK, Yang SM, Kim MJ, Kim HJ, et al. 2017. Rapid identification of Vibrio species isolated from the southern coastal regions of Korea by MALDI-TOF mass spectrometry and comparison of MALDI sample preparation methods. J. Microbiol. Biotechnol. 27: 1593-1601.
Ruaro A, Andrighetto C, Torriani S, Lombardi A. 2013. Biodiversity and characterization of indigenous coagulasenegative staphylococci isolated from raw milk and cheese of North Italy. Food Microbiol. 34: 106-111.
Haigh J, Degun A, Eydmann M, Millar M, Wilks M. 2011. Improved performance of bacterium and yeast identification by a commercial matrix-assisted laser desorption ionizationtime of flight mass spectrometry system in the clinical microbiology laboratory. J. Clin. Microbiol. 49: 3441.
Schulthess B, Brodner K, Bloemberg GV, Zbinden R, Böttger EC, Hombach M. 2013. Identification of gram-positive cocci by use of matrix-assisted laser desorption ionization-time of flight mass spectrometry: comparison of different preparation methods and implementation of a practical algorithm for routine diagnostics. J. Clin. Microbiol. 51: 1834-1840.
Takahashi T, Satoh I, Kikuchi N. 1999. Phylogenetic relationships of 38 taxa of the genus Staphylococcus based on 16S rRNA gene sequence analysis. Int. J. Syst. Bacteriol. 49:725-728.
Palys T, Nakamura LK, Cohan FM. 1997. Discovery and classification of ecological diversity in the bacterial world:the role of DNA sequence data. Int. J. Syst. Bacteriol. 47:1145-1156.
Chean R, Kotsanas D, Francis MJ, Palombo EA, Jadhav SR, Awad MM, et al. 2014. Comparing the identification of Clostridium spp. by two matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry platforms to 16S rRNA PCR sequencing as a reference standard: a detailed analysis of age of culture and sample preparation. Anaerobe 30: 85-89.
Ghebremedhin B, Layer F, König W, König B. 2008. Genetic classification and distinguishing of Staphylococcus species based on different partial gap, 16S rRNA, hsp60, rpoB, sodA, and tuf gene sequences. J. Clin. Microbiol. 46: 1019-1025.
Eigner U, Holfelder M, Oberdorfer K, Betz-Wild U, Bertsch D, Fahr AM. 2009. Performance of a matrix-assisted laser desorption ionization-time-of-flight mass spectrometry system for the identification of bacterial isolates in the clinical routine laboratory. Clin. Lab. 55: 289-296.