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Identification and Subtyping of Salmonella Isolates Using Matrix-Assisted Laser Desorption–Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF). Microorganisms 2022; 10:microorganisms10040688. [PMID: 35456741 PMCID: PMC9025770 DOI: 10.3390/microorganisms10040688] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 03/14/2022] [Accepted: 03/16/2022] [Indexed: 11/22/2022] Open
Abstract
Subtyping of bacterial isolates of the same genus and species is an important tool in epidemiological investigations. A number of phenotypic and genotypic subtyping methods are available; however, most of these methods are labor-intensive and time-consuming and require considerable operator skill and a wealth of reagents. Matrix-Assisted Laser Desorption–Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF), an alternative to conventional subtyping methods, offers a rapid, reproducible method for bacterial identification with a high sensitivity and specificity and at minimal cost. The purpose of this study was to determine the feasibility of using MALDI-TOF to differentiate between six Salmonella serovars recovered from experimental microcosms inoculated with known strains of Salmonella. Following the establishment of a MALDI-TOF reference library for this project, the identity of 843 Salmonella isolates recovered from these microcosms was assessed using both MALDI-TOF and conventional methods (serotyping/PCR). All 843 isolates were identified as being Salmonella species. Overall, 803/843 (95%) of these isolates were identified similarly using the two different methods. Positive percent agreement at the serovar level ranged from 79 to 100%, and negative percent agreement for all serovars was greater than 98%. Cohen’s kappa ranged from 0.85 to 0.98 for the different serovars. This study demonstrates that MALDI-TOF is a viable alternative for the rapid identification and differentiation of Salmonella serovars.
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Cheng W, Shi H, Teng M, Yu M, Feng B, Ding C, Yu S, Yang F. Rapid identification of bacterial mixtures in urine using MALDI-TOF MS-based algorithm profiling coupled with magnetic enrichment. Analyst 2022; 147:443-449. [PMID: 34985055 DOI: 10.1039/d1an02098f] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Urinary tract infections (UTIs) are a severe public health problem caused by mono- or poly-bacteria. Culture-based methods are routinely used for the diagnosis of UTIs in clinical practice, but those are time consuming. Rapid and unambiguous identification of each pathogen in UTIs can have a significant impact on timely diagnoses and precise treatment. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is an alternative method for the identification of pathogens in clinical laboratories. However, a certain number of pure bacteria are required for MALDI-TOF MS analysis. Here, we explored a strategy combining magnetic enrichment and MALDI-TOF MS for the rapid identification of pathogenic bacterial mixtures in urine. Fragment crystallizable mannose-binding lectin-modified Fe3O4 (Fc-MBL@Fe3O4) was used for rapid enrichment and the individual-peak-based similarity model as the analytical tool. Within 30 min, a mixture of the four most prevalent UTI-causing bacteria, Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, and Pseudomonas aeruginosa, was successfully identified using this method. This rapid MALDI-TOF MS-based strategy has potential applications in the clinical identification of UTI pathogens.
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Affiliation(s)
- Wenmin Cheng
- Zhejiang Provincial Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis, Institute of Mass Spectrometry, School of Material Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China.
| | - Haimei Shi
- Zhejiang Provincial Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis, Institute of Mass Spectrometry, School of Material Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China.
| | - Mengjing Teng
- Kweichow Moutai Group, Renhuai, Guizhou, 564501, China
| | - Menghuan Yu
- Zhejiang Provincial Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis, Institute of Mass Spectrometry, School of Material Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China.
| | - Bin Feng
- Zhejiang Provincial Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis, Institute of Mass Spectrometry, School of Material Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China.
| | - Chuanfan Ding
- Zhejiang Provincial Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis, Institute of Mass Spectrometry, School of Material Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China.
| | - Shaoning Yu
- Zhejiang Provincial Key Laboratory of Advanced Mass Spectrometry and Molecular Analysis, Institute of Mass Spectrometry, School of Material Science and Chemical Engineering, Ningbo University, Ningbo, Zhejiang 315211, China.
| | - Fan Yang
- Kweichow Moutai Group, Renhuai, Guizhou, 564501, China
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Fukuyama Y, Ojima-Kato T, Nagai S, Shima K, Funatsu S, Yamada Y, Tamura H, Nomura S, Ogata K, Sekiya S, Iwamoto S, Tanaka K. Improved MALDI-MS method for the highly sensitive and reproducible detection of biomarker peaks for the proteotyping of Salmonella serotypes. JOURNAL OF MASS SPECTROMETRY : JMS 2019; 54:966-975. [PMID: 31697871 DOI: 10.1002/jms.4469] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 10/21/2019] [Accepted: 10/23/2019] [Indexed: 06/10/2023]
Abstract
The rapid identification and classification of pathogenic microorganisms, including Salmonella enterica, is important for the surveillance and prevention of foodborne diseases. Matrix-assisted laser desorption\ionization time-of-flight mass spectrometry (MALDI-TOFMS) has been shown to be an effective tool for the rapid identification of microorganisms. In a previous report, a mass database consisting of 12 biomarker proteins, S8, L15, L17, L21, L25, S7, superoxide dismutase (SodA), peptidylprolyl cis-trans isomerase C, Gns, YibT, YaiA, and YciF, was introduced for the serotyping of S. enterica via MALDI-MS (Applied Microbiology and Biotechnology, 2017, 101, 8557-8569). However, the reproducibility of peak detection of biomarkers such as SodA at m\z 23 000 was poor. We report here an optimized MALDI-MS method for detecting these biomarkers with high sensitivity and reproducibility. The issue was solved by controlling the bacterial concentration at 1 × 10 to 1 × 102 MFU (3 × 106 to 3 × 107 CFU\μL, as calculated from the MFU), using the colony suspension supernatant obtained by centrifugation, and using matrix additives such as methylenediphosphonic acid and N-decyl-β-D-maltopyranoside. We propose that the method including the above steps is one of the best for detecting biomarkers with high sensitivity and reproducibility.
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Affiliation(s)
- Yuko Fukuyama
- Koichi Tanaka Mass Spectrometry Research Laboratory, Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Teruyo Ojima-Kato
- School of Agriculture, Meijo University, 1-501 Shiogamaguchi, Tenpaku-ku, Nagoya, Aichi, 468-0073, Japan
| | - Satomi Nagai
- School of Agriculture, Meijo University, 1-501 Shiogamaguchi, Tenpaku-ku, Nagoya, Aichi, 468-0073, Japan
| | - Keisuke Shima
- Analytical and Measuring Instruments Division, Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Shinji Funatsu
- Analytical and Measuring Instruments Division, Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Yoshihiro Yamada
- Koichi Tanaka Mass Spectrometry Research Laboratory, Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Hiroto Tamura
- School of Agriculture, Meijo University, 1-501 Shiogamaguchi, Tenpaku-ku, Nagoya, Aichi, 468-0073, Japan
| | - Shizuo Nomura
- Analytical and Measuring Instruments Division, Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Koretsugu Ogata
- Analytical and Measuring Instruments Division, Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Sadanori Sekiya
- Koichi Tanaka Mass Spectrometry Research Laboratory, Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Shinichi Iwamoto
- Koichi Tanaka Mass Spectrometry Research Laboratory, Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, 604-8511, Japan
| | - Koichi Tanaka
- Koichi Tanaka Mass Spectrometry Research Laboratory, Shimadzu Corporation, 1 Nishinokyo Kuwabara-cho, Nakagyo-ku, Kyoto, 604-8511, Japan
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Abstract
Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is now widely used to characterize bacterial samples for clinical diagnosis, food safety control, environmental monitoring, and so on. However, existing standard approaches are only applied to analyze single colonies purified by plate culture, which limits the approaches to cultivable bacteria and makes the whole approaches time-consuming. In this work, we propose a new framework to analyze MALDI-TOF spectra of bacterial mixtures and to directly characterize each component without purification procedures. The framework is a combination of a synthetic mixture model based on a non-negative linear combination of candidate reference spectra and a statistical assessment by in silico generated spectra via a jackknife resampling. Ninety-seven model bacterial mixture samples and 8 cocultured blind-coded bacterial mixture samples, containing up to 6 strains in varied ratios in each sample, together with a reference database containing the mass spectra of 1081 strains, were used to validate the framework. High sensitivity (>80%, with error rate <5%) was achieved for balanced binary and ternary mixtures. The sensitivity was >60% for balanced quaternary and pentabasic mixtures, and 48%-71% for asymmetric situation, with error rate <5%. The work can facilitate rapid and reliable characterization of bacterial mixtures without purification procedures, which is of practical value in clinical diagnosis, food safety control, environmental monitoring, and so on. The framework can be further applied to many other spectroscopy-based analytics to interpret spectra from mixed samples.
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Affiliation(s)
- Yi Yang
- Department of Chemistry, Shanghai Stomatological Hospital , Fudan University , Shanghai 200000 , China
| | - Yu Lin
- Research School of Computer Science, College of Engineering and Computer Science , The Australian National University , Canberra ACT 0200 , Australia
| | - Liang Qiao
- Department of Chemistry, Shanghai Stomatological Hospital , Fudan University , Shanghai 200000 , China
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da Silva Amaral L, Rodrigues-Filho E, Kubicek CP, Herwig C, Marchetti-Deschmann M, Allmaier G. Optimization of sample preparation for intact cell mass spectrometry (matrix-assisted laser desorption/ionization linear time-of-flight mass spectrometry) of endophytic Xylaria. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2018; 32:815-823. [PMID: 29499079 DOI: 10.1002/rcm.8098] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 02/08/2018] [Accepted: 02/21/2018] [Indexed: 06/08/2023]
Abstract
RATIONALE Although the fruiting-body of the fungi of the genus Xylaria shows a great variety of morphological characteristics, their mycelial forms are always very similar, imposing difficulties for their identification. Intact cell mass spectrometry (ICMS) using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) can be a fast and reliable strategy to support the differentiation/identification of Xylaria species in those cases where fruit-bodies are not available. METHODS Many experimental parameters such as sample preparation and culture media are crucial for filamentous fungi analysis by MALDI-TOFMS. For the purposes of this study, we used four matrices (CHCA, DHB, FA and SA) with five different concentrations (0.1, 0.3, 0.5, 1.0 and 2.5%) of TFA in the matrix, the influence of six different culture media (solid and liquid), and three mycelium peptide/protein extraction protocols (acid, basic and thymol-supported solution) to optimize the sample preparation of the endophytic fungus X. arbuscula. RESULTS It was observed that sinapinic acid (30 mg/mL) dissolved in acetonitrile/0.1% TFA and PDA were the best matrix solution and culture medium, respectively, for the ICMS of X. arbuscula. The formic acid and ammonium bicarbonate (AB) protocols provided similar mass spectra; however, a higher number of peaks were observed using AB extraction. Mass spectra obtained from different thymol-containing solutions (EtOH/aqueous 0.1% TFA and ACN/aqueous 0.1% TFA) show increasing peak abundances at m/z 3000-6500. CONCLUSIONS X. arbuscula could be analyzed by ICMS. However, an extraction step was required to provide suitable MALDI mass spectra. Formic acid-, AB- and thymol-containing solutions were demonstrated to be good cocktails for the extraction of peptide/protein biomarkers from these fungi.
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Affiliation(s)
- Luciana da Silva Amaral
- Departamento de Química, Universidade Federal de São Carlos CP 676, 13,565-905, São Carlos, SP, Brazil
- Institute of Chemical Technologies and Analytics, TU Wien (Vienna University of Technology), Getreidemarkt 9/164, A-1060, Vienna, Austria
| | - Edson Rodrigues-Filho
- Departamento de Química, Universidade Federal de São Carlos CP 676, 13,565-905, São Carlos, SP, Brazil
| | - Christian P Kubicek
- Institute of Chemical, Environmental and Bioscience Engineering, TU Wien (Vienna University of Technology), Getreidemarkt 9/166, A-1060, Vienna, Austria
| | - Christoph Herwig
- Institute of Chemical, Environmental and Bioscience Engineering, TU Wien (Vienna University of Technology), Getreidemarkt 9/166, A-1060, Vienna, Austria
| | - Martina Marchetti-Deschmann
- Institute of Chemical Technologies and Analytics, TU Wien (Vienna University of Technology), Getreidemarkt 9/164, A-1060, Vienna, Austria
| | - Günter Allmaier
- Institute of Chemical Technologies and Analytics, TU Wien (Vienna University of Technology), Getreidemarkt 9/164, A-1060, Vienna, Austria
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Sandrin TR, Demirev PA. Characterization of microbial mixtures by mass spectrometry. MASS SPECTROMETRY REVIEWS 2018; 37:321-349. [PMID: 28509357 DOI: 10.1002/mas.21534] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2016] [Revised: 03/09/2017] [Accepted: 03/09/2017] [Indexed: 05/27/2023]
Abstract
MS applications in microbiology have increased significantly in the past 10 years, due in part to the proliferation of regulator-approved commercial MALDI MS platforms for rapid identification of clinical infections. In parallel, with the expansion of MS technologies in the "omics" fields, novel MS-based research efforts to characterize organismal as well as environmental microbiomes have emerged. Successful characterization of microorganisms found in complex mixtures of other organisms remains a major challenge for researchers and clinicians alike. Here, we review recent MS advances toward addressing that challenge. These include sample preparation methods and protocols, and established, for example, MALDI, as well as newer, for example, atmospheric pressure ionization (API) techniques. MALDI mass spectra of intact cells contain predominantly information on the highly expressed house-keeping proteins used as biomarkers. The API methods are applicable for small biomolecule analysis, for example, phospholipids and lipopeptides, and facilitate species differentiation. MS hardware and techniques, for example, tandem MS, including diverse ion source/mass analyzer combinations are discussed. Relevant examples for microbial mixture characterization utilizing these combinations are provided. Chemometrics and bioinformatics methods and algorithms, including those applied to large scale MS data acquisition in microbial metaproteomics and MS imaging of biofilms, are highlighted. Select MS applications for polymicrobial culture analysis in environmental and clinical microbiology are reviewed as well.
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Affiliation(s)
- Todd R Sandrin
- School of Mathematical and Natural Sciences, Arizona State University, Phoenix, Arizona
| | - Plamen A Demirev
- Applied Physics Laboratory, Johns Hopkins University, Laurel, Maryland
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Zhang L, Smart S, Sandrin TR. Biomarker- and similarity coefficient-based approaches to bacterial mixture characterization using matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). Sci Rep 2015; 5:15834. [PMID: 26537565 PMCID: PMC4633581 DOI: 10.1038/srep15834] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2015] [Accepted: 10/01/2015] [Indexed: 01/12/2023] Open
Abstract
MALDI-TOF MS profiling has been shown to be a rapid and reliable method to characterize pure cultures of bacteria. Currently, there is keen interest in using this technique to identify bacteria in mixtures. Promising results have been reported with two- or three-isolate model systems using biomarker-based approaches. In this work, we applied MALDI-TOF MS-based methods to a more complex model mixture containing six bacteria. We employed: 1) a biomarker-based approach that has previously been shown to be useful in identification of individual bacteria in pure cultures and simple mixtures and 2) a similarity coefficient-based approach that is routinely and nearly exclusively applied to identification of individual bacteria in pure cultures. Both strategies were developed and evaluated using blind-coded mixtures. With regard to the biomarker-based approach, results showed that most peaks in mixture spectra could be assigned to those found in spectra of each component bacterium; however, peaks shared by two isolates as well as peaks that could not be assigned to any individual component isolate were observed. For two-isolate blind-coded samples, bacteria were correctly identified using both similarity coefficient- and biomarker-based strategies, while for blind-coded samples containing more than two isolates, bacteria were more effectively identified using a biomarker-based strategy.
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Affiliation(s)
- Lin Zhang
- School of Mathematical and Natural Sciences, Arizona State University, Phoenix, AZ 85069
| | - Sonja Smart
- School of Mathematical and Natural Sciences, Arizona State University, Phoenix, AZ 85069
| | - Todd R Sandrin
- School of Mathematical and Natural Sciences, Arizona State University, Phoenix, AZ 85069
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Barbano D, Diaz R, Zhang L, Sandrin T, Gerken H, Dempster T. Rapid Characterization of Microalgae and Microalgae Mixtures Using Matrix-Assisted Laser Desorption Ionization Time-Of-Flight Mass Spectrometry (MALDI-TOF MS). PLoS One 2015; 10:e0135337. [PMID: 26271045 PMCID: PMC4536233 DOI: 10.1371/journal.pone.0135337] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Accepted: 07/21/2015] [Indexed: 11/28/2022] Open
Abstract
Current molecular methods to characterize microalgae are time-intensive and expensive. Matrix Assisted Laser Desorption/Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) may represent a rapid and economical alternative approach. The objectives of this study were to determine whether MALDI-TOF MS can be used to: 1) differentiate microalgae at the species and strain levels and 2) characterize simple microalgal mixtures. A common protein extraction sample preparation method was used to facilitate rapid mass spectrometry-based analysis of 31 microalgae. Each yielded spectra containing between 6 and 56 peaks in the m/z 2,000 to 20,000 range. The taxonomic resolution of this approach appeared higher than that of 18S rDNA sequence analysis. For example, two strains of Scenedesmus acutus differed only by two 18S rDNA nucleotides, but yielded distinct MALDI-TOF mass spectra. Mixtures of two and three microalgae yielded relatively complex spectra that contained peaks associated with members of each mixture. Interestingly, though, mixture-specific peaks were observed at m/z 11,048 and 11,230. Our results suggest that MALDI-TOF MS affords rapid characterization of individual microalgae and simple microalgal mixtures.
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Affiliation(s)
- Duane Barbano
- School of Life Sciences, Arizona State University, 427 East Tyler Mall, Tempe, Arizona, United States of America
| | - Regina Diaz
- School of Life Sciences, Arizona State University, 427 East Tyler Mall, Tempe, Arizona, United States of America
| | - Lin Zhang
- School of Mathematical and Natural Sciences, Arizona State University, MC 2352, P.O. Box 37100, Phoenix, Arizona, United States of America
| | - Todd Sandrin
- School of Mathematical and Natural Sciences, Arizona State University, MC 2352, P.O. Box 37100, Phoenix, Arizona, United States of America
- * E-mail:
| | - Henri Gerken
- Arizona Center for Algae Technology and Innovation, Arizona State University, 7418 Innovation Way South, Building ISTB-3, Room 103, Mesa, Arizona, United States of America
| | - Thomas Dempster
- Arizona Center for Algae Technology and Innovation, Arizona State University, 7418 Innovation Way South, Building ISTB-3, Room 103, Mesa, Arizona, United States of America
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Santos T, Capelo JL, Santos HM, Oliveira I, Marinho C, Gonçalves A, Araújo JE, Poeta P, Igrejas G. Use of MALDI-TOF mass spectrometry fingerprinting to characterize Enterococcus spp. and Escherichia coli isolates. J Proteomics 2015; 127:321-31. [PMID: 25753124 DOI: 10.1016/j.jprot.2015.02.017] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2014] [Revised: 02/20/2015] [Accepted: 02/24/2015] [Indexed: 02/06/2023]
Abstract
UNLABELLED Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is a faster and more accurate method to identify intact bacteria than conventional microbiology and/or molecular biology methods. The MALDI-TOF MS method is potentially applicable in diagnostic laboratories to characterize commensal bacterial species, some of which are major pathogens, from human or animal gastrointestinal tracts. The aim of this study was to analyze at the cluster and statistical level the capacity of MALDI-TOF MS to distinguish between previously characterized enterococci and Escherichia coli isolated from wild birds of the Azores archipelago. Soluble proteins were extracted from intact cell cultures of 60 isolates of Enterococcus spp. and 60 isolates of E. coli by an expedient method. MALDI-TOF MS was used to obtain 1200 mass spectra that were statistically analyzed and compared. A total of 215 distinct mass-to-charge (m/z) peaks were obtained, including a peak at m/z 4428±3, which is exclusively found in spectra from Enterococcus isolates, and peaks at m/z 5379±3 and m/z 6253±3, which are only detected in spectra from E. coli isolates. By processing mass spectra and analyzing them statistically with MassUp software, including principal component analysis (PCA) and clustering, it was possible to correctly distinguish between isolates of Enterococcus and Escherichia genera. The results of the proteomic analysis confirm that these tools could be used to characterize whole bacterial cells. In the future, with an optimized protocol for obtaining plasmid-associated proteins and the further development of bioinformatics methods, it is likely that mass peak characteristic of antimicrobial resistance will be detected, increasing the potential usefulness of MALDI-TOF in routine clinical assays. BIOLOGICAL SIGNIFICANCE This study highlights the importance of MALDI-TOF MS in the rapid and reliable identification of bacteria by whole-cell analysis. The mass spectrometry approach performed in this study further contributes for the microbial biomarker discovery culminating in a preferable bacteria identification and antimicrobial resistance tool for the future of clinical microbiology. This article is part of a Special Issue entitled: HUPO 2014.
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Affiliation(s)
- Tiago Santos
- Institute for Biotechnology and Bioengineering, Centre of Genomics and Biotechnology, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal; Department of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
| | - José Luis Capelo
- Bioscope Group, Departamento de Química, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, Caparica, Portugal; REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, Caparica, Portugal
| | - Hugo M Santos
- Bioscope Group, Departamento de Química, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, Caparica, Portugal; REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, Caparica, Portugal
| | - Irene Oliveira
- Centre for the Research and Technology of Agro-Environmental and Biological Sciences, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
| | - Catarina Marinho
- Institute for Biotechnology and Bioengineering, Centre of Genomics and Biotechnology, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal; Department of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
| | - Alexandre Gonçalves
- Institute for Biotechnology and Bioengineering, Centre of Genomics and Biotechnology, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal; Department of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
| | - José Eduardo Araújo
- Bioscope Group, Departamento de Química, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, Caparica, Portugal; REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, FCT, Universidade Nova de Lisboa, Caparica, Portugal
| | - Patrícia Poeta
- Centre of Studies of Animal and Veterinary Sciences, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal; Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal
| | - Gilberto Igrejas
- Institute for Biotechnology and Bioengineering, Centre of Genomics and Biotechnology, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal; Department of Genetics and Biotechnology, University of Trás-os-Montes and Alto Douro, Vila Real, Portugal.
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