151
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Singh C, Glaab E, Linster CL. Molecular Identification of d-Ribulokinase in Budding Yeast and Mammals. J Biol Chem 2016; 292:1005-1028. [PMID: 27909055 DOI: 10.1074/jbc.m116.760744] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2016] [Revised: 11/29/2016] [Indexed: 12/13/2022] Open
Abstract
Proteomes of even well characterized organisms still contain a high percentage of proteins with unknown or uncertain molecular and/or biological function. A significant fraction of those proteins is predicted to have catalytic properties. Here we aimed at identifying the function of the Saccharomyces cerevisiae Ydr109c protein and its human homolog FGGY, both of which belong to the broadly conserved FGGY family of carbohydrate kinases. Functionally identified members of this family phosphorylate 3- to 7-carbon sugars or sugar derivatives, but the endogenous substrate of S. cerevisiae Ydr109c and human FGGY has remained unknown. Untargeted metabolomics analysis of an S. cerevisiae deletion mutant of YDR109C revealed ribulose as one of the metabolites with the most significantly changed intracellular concentration as compared with a wild-type strain. In human HEK293 cells, ribulose could only be detected when ribitol was added to the cultivation medium, and under this condition, FGGY silencing led to ribulose accumulation. Biochemical characterization of the recombinant purified Ydr109c and FGGY proteins showed a clear substrate preference of both kinases for d-ribulose over a range of other sugars and sugar derivatives tested, including l-ribulose. Detailed sequence and structural analyses of Ydr109c and FGGY as well as homologs thereof furthermore allowed the definition of a 5-residue d-ribulokinase signature motif (TCSLV). The physiological role of the herein identified eukaryotic d-ribulokinase remains unclear, but we speculate that S. cerevisiae Ydr109c and human FGGY could act as metabolite repair enzymes, serving to re-phosphorylate free d-ribulose generated by promiscuous phosphatases from d-ribulose 5-phosphate. In human cells, FGGY can additionally participate in ribitol metabolism.
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Affiliation(s)
- Charandeep Singh
- From the Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4362 Esch-sur-Alzette, Luxembourg
| | - Enrico Glaab
- From the Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4362 Esch-sur-Alzette, Luxembourg
| | - Carole L Linster
- From the Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4362 Esch-sur-Alzette, Luxembourg
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152
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van der Hooft JJJ, Wandy J, Barrett MP, Burgess KEV, Rogers S. Topic modeling for untargeted substructure exploration in metabolomics. Proc Natl Acad Sci U S A 2016; 113:13738-13743. [PMID: 27856765 PMCID: PMC5137707 DOI: 10.1073/pnas.1608041113] [Citation(s) in RCA: 196] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The potential of untargeted metabolomics to answer important questions across the life sciences is hindered because of a paucity of computational tools that enable extraction of key biochemically relevant information. Available tools focus on using mass spectrometry fragmentation spectra to identify molecules whose behavior suggests they are relevant to the system under study. Unfortunately, fragmentation spectra cannot identify molecules in isolation but require authentic standards or databases of known fragmented molecules. Fragmentation spectra are, however, replete with information pertaining to the biochemical processes present, much of which is currently neglected. Here, we present an analytical workflow that exploits all fragmentation data from a given experiment to extract biochemically relevant features in an unsupervised manner. We demonstrate that an algorithm originally used for text mining, latent Dirichlet allocation, can be adapted to handle metabolomics datasets. Our approach extracts biochemically relevant molecular substructures ("Mass2Motifs") from spectra as sets of co-occurring molecular fragments and neutral losses. The analysis allows us to isolate molecular substructures, whose presence allows molecules to be grouped based on shared substructures regardless of classical spectral similarity. These substructures, in turn, support putative de novo structural annotation of molecules. Combining this spectral connectivity to orthogonal correlations (e.g., common abundance changes under system perturbation) significantly enhances our ability to provide mechanistic explanations for biological behavior.
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Affiliation(s)
- Justin Johan Jozias van der Hooft
- Glasgow Polyomics, University of Glasgow, Glasgow G61 1QH, United Kingdom
- Institute of Infection, Immunity, and Inflammation, College of Medical, Veterinary, and Life Sciences, University of Glasgow, Glasgow G12 8TA, United Kingdom
| | - Joe Wandy
- Glasgow Polyomics, University of Glasgow, Glasgow G61 1QH, United Kingdom
- School of Computing Science, University of Glasgow, Glasgow G12 8RZ, United Kingdom
| | - Michael P Barrett
- Glasgow Polyomics, University of Glasgow, Glasgow G61 1QH, United Kingdom
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow G12 8TA, United Kingdom
| | - Karl E V Burgess
- Glasgow Polyomics, University of Glasgow, Glasgow G61 1QH, United Kingdom
| | - Simon Rogers
- Glasgow Polyomics, University of Glasgow, Glasgow G61 1QH, United Kingdom;
- School of Computing Science, University of Glasgow, Glasgow G12 8RZ, United Kingdom
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153
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Weidt S, Haggarty J, Kean R, Cojocariu CI, Silcock PJ, Rajendran R, Ramage G, Burgess KEV. A novel targeted/untargeted GC-Orbitrap metabolomics methodology applied to Candida albicans and Staphylococcus aureus biofilms. Metabolomics 2016; 12:189. [PMID: 28003796 PMCID: PMC5097782 DOI: 10.1007/s11306-016-1134-2] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2016] [Accepted: 10/18/2016] [Indexed: 10/26/2022]
Abstract
INTRODUCTION Combined infections from Candida albicans and Staphylococcus aureus are a leading cause of death in the developed world. Evidence suggests that Candida enhances the virulence of Staphylococcus-hyphae penetrate through tissue barriers, while S. aureus tightly associates with the hyphae to obtain entry to the host organism. Indeed, in a biofilm state, C. albicans enhances the antimicrobial resistance characteristics of S. aureus. The association of these microorganisms is also associated with significantly increased morbidity and mortality. Due to this tight association we hypothesised that metabolic effects were also in evidence. OBJECTIVES To explore the interaction, we used a novel GC-Orbitrap-based mass spectrometer, the Q Exactive GC, which combines the high peak capacity and chromatographic resolution of gas chromatography with the sub-ppm mass accuracy of an Orbitrap system. This allows the capability to leverage the widely available electron ionisation libraries for untargeted applications, along with expanding accurate mass libraries and targeted matches based around authentic standards. METHODS Optimised C. albicans and S. aureus mono- and co-cultured biofilms were analysed using the new instrument in addition to the fresh and spent bacterial growth media. RESULTS The targeted analysis experiment was based around 36 sugars and sugar phosphates, 22 amino acids and five organic acids. Untargeted analysis resulted in the detection of 465 features from fresh and spent medium and 405 from biofilm samples. Three significantly changing compounds that matched to high scoring library fragment patterns were chosen for validation. CONCLUSION Evaluation of the results demonstrates that the Q Exactive GC is suitable for metabolomics analysis using a targeted/untargeted methodology. Many of the results were as expected: e.g. rapid consumption of glucose and fructose from the medium regardless of the cell type. Modulation of sugar-phosphate levels also suggest that the pentose phosphate pathway could be enhanced in the cells from co-cultured biofilms. Untargeted metabolomics results suggested significant production of cell-wall biosynthesis components and the consumption of non-proteinaceous amino-acids.
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Affiliation(s)
- Stefan Weidt
- Polyomics, University of Glasgow, 211 Wolfson Wohl Translational Cancer Research Centre, Garscube Campus, Glasgow, G61 1QH UK
| | - Jennifer Haggarty
- Polyomics, University of Glasgow, 211 Wolfson Wohl Translational Cancer Research Centre, Garscube Campus, Glasgow, G61 1QH UK
| | - Ryan Kean
- Oral Sciences Research Group, Glasgow Dental School, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | | | | | - Ranjith Rajendran
- Oral Sciences Research Group, Glasgow Dental School, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Gordon Ramage
- Oral Sciences Research Group, Glasgow Dental School, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Karl E. V. Burgess
- Polyomics, University of Glasgow, 211 Wolfson Wohl Translational Cancer Research Centre, Garscube Campus, Glasgow, G61 1QH UK
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154
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Metabolomics-Based Screening of the Malaria Box Reveals both Novel and Established Mechanisms of Action. Antimicrob Agents Chemother 2016; 60:6650-6663. [PMID: 27572396 DOI: 10.1128/aac.01226-16] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2016] [Accepted: 08/16/2016] [Indexed: 12/22/2022] Open
Abstract
High-throughput phenotypic screening of chemical libraries has resulted in the identification of thousands of compounds with potent antimalarial activity, although in most cases, the mechanism(s) of action of these compounds remains unknown. Here we have investigated the mode of action of 90 antimalarial compounds derived from the Malaria Box collection using high-coverage, untargeted metabolomics analysis. Approximately half of the tested compounds induced significant metabolic perturbations in in vitro cultures of Plasmodium falciparum In most cases, the metabolic profiles were highly correlated with known antimalarials, in particular artemisinin, the 4-aminoquinolines, or atovaquone. Select Malaria Box compounds also induced changes in intermediates in essential metabolic pathways, such as isoprenoid biosynthesis (i.e., 2-C-methyl-d-erythritol 2,4-cyclodiphosphate) and linolenic acid metabolism (i.e., traumatic acid). This study provides a comprehensive database of the metabolic perturbations induced by chemically diverse inhibitors and highlights the utility of metabolomics for triaging new lead compounds and defining specific modes of action, which will assist with the development and optimization of new antimalarial drugs.
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155
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Ríos Peces S, Díaz Navarro C, Márquez López C, Caba O, Jiménez-Luna C, Melguizo C, Prados JC, Genilloud O, Vicente Pérez F, Pérez Del Palacio J. Untargeted LC-HRMS-Based Metabolomics for Searching New Biomarkers of Pancreatic Ductal Adenocarcinoma: A Pilot Study. SLAS DISCOVERY 2016; 22:348-359. [PMID: 27655283 DOI: 10.1177/1087057116671490] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Pancreatic ductal adenocarcinoma is one of the most lethal tumors since it is usually detected at an advanced stage in which surgery and/or current chemotherapy have limited efficacy. The lack of sensitive and specific markers for diagnosis leads to a dismal prognosis. The purpose of this study is to identify metabolites in serum of pancreatic ductal adenocarcinoma patients that could be used as diagnostic biomarkers of this pathology. We used liquid chromatography-high-resolution mass spectrometry for a nontargeted metabolomics approach with serum samples from 28 individuals, including 16 patients with pancreatic ductal adenocarcinoma and 12 healthy controls. Multivariate statistical analysis, which included principal component analysis and partial least squares, revealed clear separation between the patient and control groups analyzed by liquid chromatography-high-resolution mass spectrometry using a nontargeted metabolomics approach. The metabolic analysis showed significantly lower levels of phospholipids in the serum from patients with pancreatic ductal adenocarcinoma compared with serum from controls. Our results suggest that the liquid chromatography-high-resolution mass spectrometry-based metabolomics approach provides a potent and promising tool for the diagnosis of pancreatic ductal adenocarcinoma patients using the specific metabolites identified as novel biomarkers that could be used for an earlier detection and treatment of these patients.
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Affiliation(s)
- Sandra Ríos Peces
- 1 Fundación MEDINA, Centro de Excelencia en Investigación de Medicamentos Innovadores en Andalucía, Granada, Spain
| | - Caridad Díaz Navarro
- 1 Fundación MEDINA, Centro de Excelencia en Investigación de Medicamentos Innovadores en Andalucía, Granada, Spain
| | - Cristina Márquez López
- 2 Fundacion Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC), Madrid, Spain
| | - Octavio Caba
- 3 Department of Health Science, University of Jaen, Jaen, Spain.,4 Institute of Biopathology and Regenerative Medicine (IBIMER), Center of Biomedical Research (CIBM), University of Granada, Granada, Spain
| | - Cristina Jiménez-Luna
- 4 Institute of Biopathology and Regenerative Medicine (IBIMER), Center of Biomedical Research (CIBM), University of Granada, Granada, Spain.,5 Department of Anatomy and Embryology, Faculty of Medicine, University of Granada, Granada, Spain
| | - Consolación Melguizo
- 4 Institute of Biopathology and Regenerative Medicine (IBIMER), Center of Biomedical Research (CIBM), University of Granada, Granada, Spain.,6 Biosanitary Institute of Granada (ibs. GRANADA), SAS-Universidad de Granada, Granada, Spain
| | - José Carlos Prados
- 4 Institute of Biopathology and Regenerative Medicine (IBIMER), Center of Biomedical Research (CIBM), University of Granada, Granada, Spain.,6 Biosanitary Institute of Granada (ibs. GRANADA), SAS-Universidad de Granada, Granada, Spain
| | - Olga Genilloud
- 1 Fundación MEDINA, Centro de Excelencia en Investigación de Medicamentos Innovadores en Andalucía, Granada, Spain
| | - Francisca Vicente Pérez
- 1 Fundación MEDINA, Centro de Excelencia en Investigación de Medicamentos Innovadores en Andalucía, Granada, Spain
| | - José Pérez Del Palacio
- 1 Fundación MEDINA, Centro de Excelencia en Investigación de Medicamentos Innovadores en Andalucía, Granada, Spain
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156
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Optimized Method for Untargeted Metabolomics Analysis of MDA-MB-231 Breast Cancer Cells. Metabolites 2016; 6:metabo6040030. [PMID: 27669323 PMCID: PMC5192436 DOI: 10.3390/metabo6040030] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2016] [Revised: 09/15/2016] [Accepted: 09/19/2016] [Indexed: 12/12/2022] Open
Abstract
Cancer cells often have dysregulated metabolism, which is largely characterized by the Warburg effect-an increase in glycolytic activity at the expense of oxidative phosphorylation-and increased glutamine utilization. Modern metabolomics tools offer an efficient means to investigate metabolism in cancer cells. Currently, a number of protocols have been described for harvesting adherent cells for metabolomics analysis, but the techniques vary greatly and they lack specificity to particular cancer cell lines with diverse metabolic and structural features. Here we present an optimized method for untargeted metabolomics characterization of MDA-MB-231 triple negative breast cancer cells, which are commonly used to study metastatic breast cancer. We found that an approach that extracted all metabolites in a single step within the culture dish optimally detected both polar and non-polar metabolite classes with higher relative abundance than methods that involved removal of cells from the dish. We show that this method is highly suited to diverse applications, including the characterization of central metabolic flux by stable isotope labelling and differential analysis of cells subjected to specific pharmacological interventions.
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157
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Falchi F, Bertozzi SM, Ottonello G, Ruda GF, Colombano G, Fiorelli C, Martucci C, Bertorelli R, Scarpelli R, Cavalli A, Bandiera T, Armirotti A. Kernel-Based, Partial Least Squares Quantitative Structure-Retention Relationship Model for UPLC Retention Time Prediction: A Useful Tool for Metabolite Identification. Anal Chem 2016; 88:9510-9517. [DOI: 10.1021/acs.analchem.6b02075] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Federico Falchi
- Drug
Discovery and Development Department, Fondazione Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Sine Mandrup Bertozzi
- Drug
Discovery and Development Department, Fondazione Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Giuliana Ottonello
- Drug
Discovery and Development Department, Fondazione Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Gian Filippo Ruda
- Drug
Discovery and Development Department, Fondazione Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Giampiero Colombano
- Drug
Discovery and Development Department, Fondazione Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Claudio Fiorelli
- Drug
Discovery and Development Department, Fondazione Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Cataldo Martucci
- Drug
Discovery and Development Department, Fondazione Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Rosalia Bertorelli
- Drug
Discovery and Development Department, Fondazione Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Rita Scarpelli
- Drug
Discovery and Development Department, Fondazione Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Andrea Cavalli
- Drug
Discovery and Development Department, Fondazione Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
- Department
of Pharmacy and Biotechnology, University of Bologna, Via Belmeloro
6, 40126 Bologna, Italy
| | - Tiziano Bandiera
- Drug
Discovery and Development Department, Fondazione Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
| | - Andrea Armirotti
- Drug
Discovery and Development Department, Fondazione Istituto Italiano di Tecnologia, Via Morego 30, 16163 Genova, Italy
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158
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Broeckling CD, Ganna A, Layer M, Brown K, Sutton B, Ingelsson E, Peers G, Prenni JE. Enabling Efficient and Confident Annotation of LC-MS Metabolomics Data through MS1 Spectrum and Time Prediction. Anal Chem 2016; 88:9226-34. [PMID: 27560453 DOI: 10.1021/acs.analchem.6b02479] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Liquid chromatography coupled to electrospray ionization-mass spectrometry (LC-ESI-MS) is a versatile and robust platform for metabolomic analysis. However, while ESI is a soft ionization technique, in-source phenomena including multimerization, nonproton cation adduction, and in-source fragmentation complicate interpretation of MS data. Here, we report chromatographic and mass spectrometric behavior of 904 authentic standards collected under conditions identical to a typical nontargeted profiling experiment. The data illustrate that the often high level of complexity in MS spectra is likely to result in misinterpretation during the annotation phase of the experiment and a large overestimation of the number of compounds detected. However, our analysis of this MS spectral library data indicates that in-source phenomena are not random but depend at least in part on chemical structure. These nonrandom patterns enabled predictions to be made as to which in-source signals are likely to be observed for a given compound. Using the authentic standard spectra as a training set, we modeled the in-source phenomena for all compounds in the Human Metabolome Database to generate a theoretical in-source spectrum and retention time library. A novel spectral similarity matching platform was developed to facilitate efficient spectral searching for nontargeted profiling applications. Taken together, this collection of experimental spectral data, predictive modeling, and informatic tools enables more efficient, reliable, and transparent metabolite annotation.
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Affiliation(s)
- Corey D Broeckling
- Proteomics and Metabolomics Facility, Colorado State University , C-121 Microbiology Building, 2021 Campus Delivery, Fort Collins, Colorado 80523, United States
| | - Andrea Ganna
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard and Analytical and Translational Genetics Unit, Department of Medicine, Massachusetts General Hospital and Harvard Medical School , Boston, Massachusetts 02114, United States
| | - Mark Layer
- Research Software Facility, Soil and Crop Sciences, Colorado State University , Fort Collins, Colorado 80523, United States.,Department of Biology, Colorado State University , Fort Collins, Colorado 80523, United States
| | - Kevin Brown
- Research Software Facility, Soil and Crop Sciences, Colorado State University , Fort Collins, Colorado 80523, United States
| | - Ben Sutton
- Research Software Facility, Soil and Crop Sciences, Colorado State University , Fort Collins, Colorado 80523, United States
| | - Erik Ingelsson
- Department of Medicine, Division of Cardiovascular Medicine, Stanford University School of Medicine , Stanford, California 94305, United States
| | - Graham Peers
- Department of Biology, Colorado State University , Fort Collins, Colorado 80523, United States
| | - Jessica E Prenni
- Proteomics and Metabolomics Facility, Colorado State University , C-121 Microbiology Building, 2021 Campus Delivery, Fort Collins, Colorado 80523, United States
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159
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Tang DQ, Zou L, Yin XX, Ong CN. HILIC-MS for metabolomics: An attractive and complementary approach to RPLC-MS. MASS SPECTROMETRY REVIEWS 2016; 35:574-600. [PMID: 25284160 DOI: 10.1002/mas.21445] [Citation(s) in RCA: 121] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2014] [Accepted: 07/28/2014] [Indexed: 05/14/2023]
Abstract
Hydrophilic interaction chromatography (HILIC) is an emerging separation mode of liquid chromatography (LC). Using highly hydrophilic stationary phases capable of retaining polar/ionic metabolites, and accompany with high organic content mobile phase that offer readily compatibility with mass spectrometry (MS) has made HILIC an attractive complementary tool to the widely used reverse-phase (RP) chromatographic separations in metabolomic studies. The combination of HILIC and RPLC coupled with an MS detector expands the number of detected analytes and provides more comprehensive metabolite coverage than use of only RP chromatography. This review describes the recent applications of HILIC-MS/MS in metabolomic studies, ranging from amino acids, lipids, nucleotides, organic acids, pharmaceuticals, and metabolites of specific nature. The biological systems investigated include microbials, cultured cell line, plants, herbal medicine, urine, and serum as well as tissues from animals and humans. Owing to its unique capability to measure more-polar biomolecules, the HILIC separation technique would no doubt enhance the comprehensiveness of metabolite detection, and add significant value for metabolomic investigations. © 2014 Wiley Periodicals, Inc. Mass Spec Rev 35:574-600, 2016.
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Affiliation(s)
- Dao-Quan Tang
- Department of Pharmaceutical Analysis, Xuzhou Medical College, Xuzhou, 221044, China
- Jiangsu Key Lab for the study of New Drug and Clinical Pharmacy, Xuzhou Medical College, Yunlong, China
- NUS Environmental Research Inst., National University of Singapore, 5 A Engineering Srive 1, Singapore, 117411, Singapore
| | - Ll Zou
- Saw Swee Hock School of Public Health, National University of Singapore, 16 Medical Drive, Singapore, 117597, Singapore
| | - Xiao-Xing Yin
- Jiangsu Key Lab for the study of New Drug and Clinical Pharmacy, Xuzhou Medical College, Yunlong, China
| | - Choon Nam Ong
- NUS Environmental Research Inst., National University of Singapore, 5 A Engineering Srive 1, Singapore, 117411, Singapore
- Saw Swee Hock School of Public Health, National University of Singapore, 16 Medical Drive, Singapore, 117597, Singapore
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160
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Shahaf N, Rogachev I, Heinig U, Meir S, Malitsky S, Battat M, Wyner H, Zheng S, Wehrens R, Aharoni A. The WEIZMASS spectral library for high-confidence metabolite identification. Nat Commun 2016; 7:12423. [PMID: 27571918 PMCID: PMC5013563 DOI: 10.1038/ncomms12423] [Citation(s) in RCA: 68] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2015] [Accepted: 06/27/2016] [Indexed: 12/25/2022] Open
Abstract
Annotation of metabolites is an essential, yet problematic, aspect of mass spectrometry (MS)-based metabolomics assays. The current repertoire of definitive annotations of metabolite spectra in public MS databases is limited and suffers from lack of chemical and taxonomic diversity. Furthermore, the heterogeneity of the data prevents the development of universally applicable metabolite annotation tools. Here we present a combined experimental and computational platform to advance this key issue in metabolomics. WEIZMASS is a unique reference metabolite spectral library developed from high-resolution MS data acquired from a structurally diverse set of 3,540 plant metabolites. We also present MatchWeiz, a multi-module strategy using a probabilistic approach to match library and experimental data. This strategy allows efficient and high-confidence identification of dozens of metabolites in model and exotic plants, including metabolites not previously reported in plants or found in few plant species to date. Unambiguous metabolite annotation is a critical, yet problematic step, in mass spectrometry based metabolomics. Here, Shahaf et al. present WEIZMASS, a platform consisting of a diverse spectral library of more than 3500 plant metabolites and software to aid their identification in biological samples.
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Affiliation(s)
- Nir Shahaf
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, PO Box 26, Rehovot 7610001, Israel.,Institute of Plant Sciences, Robert H. Smith Faculty of Agriculture, Food and Environment, The Hebrew University of Jerusalem, PO Box 12, Rehovot 76100, Israel.,Research and Innovation Centre, Fondazione E. Mach, San Michele all'Adige, 38010 Trento, Italy
| | - Ilana Rogachev
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, PO Box 26, Rehovot 7610001, Israel
| | - Uwe Heinig
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, PO Box 26, Rehovot 7610001, Israel
| | - Sagit Meir
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, PO Box 26, Rehovot 7610001, Israel
| | - Sergey Malitsky
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, PO Box 26, Rehovot 7610001, Israel
| | - Maor Battat
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, PO Box 26, Rehovot 7610001, Israel
| | - Hilary Wyner
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, PO Box 26, Rehovot 7610001, Israel
| | - Shuning Zheng
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, PO Box 26, Rehovot 7610001, Israel
| | - Ron Wehrens
- Research and Innovation Centre, Fondazione E. Mach, San Michele all'Adige, 38010 Trento, Italy.,Wageningen University and Research, Droevendaalsesteeg 1, Wageningen 6708 PB, The Netherlands
| | - Asaph Aharoni
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, PO Box 26, Rehovot 7610001, Israel
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161
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West C, Auroux E. Deconvoluting the effects of buffer salt concentration in hydrophilic interaction chromatography on a zwitterionic stationary phase. J Chromatogr A 2016; 1461:92-7. [DOI: 10.1016/j.chroma.2016.07.059] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Revised: 07/21/2016] [Accepted: 07/22/2016] [Indexed: 11/29/2022]
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162
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Alakpa E, Jayawarna V, Lampel A, Burgess K, West C, Bakker S, Roy S, Javid N, Fleming S, Lamprou D, Yang J, Miller A, Urquhart A, Frederix P, Hunt N, Péault B, Ulijn R, Dalby M. Tunable Supramolecular Hydrogels for Selection of Lineage-Guiding Metabolites in Stem Cell Cultures. Chem 2016. [DOI: 10.1016/j.chempr.2016.07.001] [Citation(s) in RCA: 83] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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163
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Roberts J, Sahoo JK, McNamara LE, Burgess KV, Yang J, Alakpa EV, Anderson HJ, Hay J, Turner LA, Yarwood SJ, Zelzer M, Oreffo RC, Ulijn RV, Dalby MJ. Dynamic Surfaces for the Study of Mesenchymal Stem Cell Growth through Adhesion Regulation. ACS NANO 2016; 10:6667-79. [PMID: 27322014 PMCID: PMC4963921 DOI: 10.1021/acsnano.6b01765] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2016] [Accepted: 06/20/2016] [Indexed: 05/18/2023]
Abstract
Out of their niche environment, adult stem cells, such as mesenchymal stem cells (MSCs), spontaneously differentiate. This makes both studying these important regenerative cells and growing large numbers of stem cells for clinical use challenging. Traditional cell culture techniques have fallen short of meeting this challenge, but materials science offers hope. In this study, we have used emerging rules of managing adhesion/cytoskeletal balance to prolong MSC cultures by fabricating controllable nanoscale cell interfaces using immobilized peptides that may be enzymatically activated to change their function. The surfaces can be altered (activated) at will to tip adhesion/cytoskeletal balance and initiate differentiation, hence better informing biological mechanisms of stem cell growth. Tools that are able to investigate the stem cell phenotype are important. While large phenotypical differences, such as the difference between an adipocyte and an osteoblast, are now better understood, the far more subtle differences between fibroblasts and MSCs are much harder to dissect. The development of technologies able to dynamically navigate small differences in adhesion are critical in the race to provide regenerative strategies using stem cells.
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Affiliation(s)
- Jemma
N. Roberts
- Centre
for Cell Engineering, Institute of Molecular, Cell and Systems Biology,
College of Medical, Veterinary and Life Sciences, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ, Scotland, U.K.
| | - Jugal Kishore Sahoo
- Department
of Pure & Applied Chemistry, WestCHEM, Thomas Graham Building, 295 Cathedral
Street, Glasgow G1 1XL, Scotland, U.K.
| | - Laura E. McNamara
- Centre
for Cell Engineering, Institute of Molecular, Cell and Systems Biology,
College of Medical, Veterinary and Life Sciences, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ, Scotland, U.K.
| | - Karl V. Burgess
- Glasgow
Polyomics Facility, Translational Cancer Research Centre, University of Glasgow Garscube Campus, Switchback Road, Glasgow G61 1QH, Scotland, U.K.
| | - Jingli Yang
- Centre
for Cell Engineering, Institute of Molecular, Cell and Systems Biology,
College of Medical, Veterinary and Life Sciences, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ, Scotland, U.K.
| | - Enateri V. Alakpa
- Centre
for Cell Engineering, Institute of Molecular, Cell and Systems Biology,
College of Medical, Veterinary and Life Sciences, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ, Scotland, U.K.
| | - Hilary J. Anderson
- Centre
for Cell Engineering, Institute of Molecular, Cell and Systems Biology,
College of Medical, Veterinary and Life Sciences, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ, Scotland, U.K.
| | - Jake Hay
- Centre
for Cell Engineering, Institute of Molecular, Cell and Systems Biology,
College of Medical, Veterinary and Life Sciences, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ, Scotland, U.K.
| | - Lesley-Anne Turner
- Centre
for Cell Engineering, Institute of Molecular, Cell and Systems Biology,
College of Medical, Veterinary and Life Sciences, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ, Scotland, U.K.
| | - Stephen J. Yarwood
- Centre
for Cell Engineering, Institute of Molecular, Cell and Systems Biology,
College of Medical, Veterinary and Life Sciences, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ, Scotland, U.K.
| | - Mischa Zelzer
- School
of Pharmacy, University of Nottingham, Boots Science Building, University Park, Nottingham NG7 2RD, U.K.
- National
Physical Laboratory, Teddington, Middlesex TW11 0LW, U.K.
| | - Richard
O. C. Oreffo
- Bone
&
Joint Research Group, Centre for Human Development, Stem Cells and
Regeneration, Institute of Developmental Sciences, University of Southampton, Southampton SO16 6YD, U.K.
| | - Rein V. Ulijn
- Department
of Pure & Applied Chemistry, WestCHEM, Thomas Graham Building, 295 Cathedral
Street, Glasgow G1 1XL, Scotland, U.K.
- Advanced
Science Research Center (ASRC), City University
of New York, New York, New York 10031, United
States
- Department
of Chemistry and Biochemistry, City University
of New York—Hunter College, 695 Park Avenue, New York, New York 10065, United
States
| | - Matthew J. Dalby
- Centre
for Cell Engineering, Institute of Molecular, Cell and Systems Biology,
College of Medical, Veterinary and Life Sciences, Joseph Black Building, University of Glasgow, Glasgow G12 8QQ, Scotland, U.K.
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164
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Ammann AA, Suter MJF. Multimode gradient high performance liquid chromatography mass spectrometry method applicable to metabolomics and environmental monitoring. J Chromatogr A 2016; 1456:145-51. [DOI: 10.1016/j.chroma.2016.06.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Revised: 04/25/2016] [Accepted: 06/01/2016] [Indexed: 11/16/2022]
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165
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Christophoridis C, Nika MC, Aalizadeh R, Thomaidis NS. Ozonation of ranitidine: Effect of experimental parameters and identification of transformation products. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 557-558:170-182. [PMID: 27133934 DOI: 10.1016/j.scitotenv.2016.03.026] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2015] [Revised: 02/16/2016] [Accepted: 03/04/2016] [Indexed: 06/05/2023]
Abstract
This study focuses on the effect of experimental parameters on the removal of ranitidine (RAN) during ozonation and the identification of the formed transformation products (TPs). The influence of pH value, the initial concentrations, the inorganic and the organic matter on RAN's removal were evaluated. Results indicated high reactivity of RAN with molecular aqueous ozone. Initial ozone concentration and pH were proven the major process parameters. Alkaline pH values promoted degradation and overall mineralization. Dissolved organic matter reacts competitively to RAN with the oxidants (ozone and/or radicals), influencing the target compound's removal. The presence of inorganic ions in the matrix did not seem to affect RAN ozonation. A total of eleven TPs were identified and structurally elucidated, with the complementary use of both Reversed Phase (RP) and Hydrophilic Interaction Liquid Chromatography (HILIC) quadrupole time of flight tandem mass spectrometry (Q-ToF-MS/MS). Most of the TPs (TP-304, TP-315b, TP-299b, TP-333, TP-283) were generated by the attack of ozone at the double bond or the adjacent secondary amine, with the abstraction of NO2 moiety, forming TPs with an aldehyde group and an imine bond. Oxidized derivatives with a carboxylic group (TP-315a, TP-331a, TP-331b, TP-299a) were also formed. RAN S-oxide was identified as an ozonation TP (TP-330) and its structure was confirmed through the analysis of a reference standard. TP-214 was also produced during ozonation, through the CN bond rupture adjacent to the NO2 moiety. HILIC was used complementary to RP, either for the separation and identification of TPs with isomeric structures that may have been co-eluted in RPLC or for the detection of new TPs that were not eluted in the RP chromatographic system. Retention time prediction was used as a supporting tool for the identification of TPs and results were in accordance with the experimental ones in both RP and HILIC.
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Affiliation(s)
- Christophoros Christophoridis
- Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Zografou, Athens 15771, Greece
| | - Maria-Christina Nika
- Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Zografou, Athens 15771, Greece
| | - Reza Aalizadeh
- Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Zografou, Athens 15771, Greece
| | - Nikolaos S Thomaidis
- Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Zografou, Athens 15771, Greece.
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166
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Aalizadeh R, Thomaidis NS, Bletsou AA, Gago-Ferrero P. Quantitative Structure-Retention Relationship Models To Support Nontarget High-Resolution Mass Spectrometric Screening of Emerging Contaminants in Environmental Samples. J Chem Inf Model 2016; 56:1384-98. [PMID: 27266383 DOI: 10.1021/acs.jcim.5b00752] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Affiliation(s)
- Reza Aalizadeh
- Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis Zografou, 15771 Athens, Greece
| | - Nikolaos S Thomaidis
- Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis Zografou, 15771 Athens, Greece
| | - Anna A Bletsou
- Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis Zografou, 15771 Athens, Greece
| | - Pablo Gago-Ferrero
- Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens , Panepistimiopolis Zografou, 15771 Athens, Greece
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167
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Kurczy ME, Forsberg EM, Thorgersen MP, Poole FL, Benton HP, Ivanisevic J, Tran ML, Wall JD, Elias DA, Adams MWW, Siuzdak G. Global Isotope Metabolomics Reveals Adaptive Strategies for Nitrogen Assimilation. ACS Chem Biol 2016; 11:1677-85. [PMID: 27045776 DOI: 10.1021/acschembio.6b00082] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Nitrogen cycling is a microbial metabolic process essential for global ecological/agricultural balance. To investigate the link between the well-established ammonium and the alternative nitrate assimilation metabolic pathways, global isotope metabolomics was employed to examine three nitrate reducing bacteria using (15)NO3 as a nitrogen source. In contrast to a control (Pseudomonas stutzeri RCH2), the results show that two of the isolates from Oak Ridge, Tennessee (Pseudomonas N2A2 and N2E2) utilize nitrate and ammonia for assimilation concurrently with differential labeling observed across multiple classes of metabolites including amino acids and nucleotides. The data reveal that the N2A2 and N2E2 strains conserve nitrogen-containing metabolites, indicating that the nitrate assimilation pathway is a conservation mechanism for the assimilation of nitrogen. Co-utilization of nitrate and ammonia is likely an adaption to manage higher levels of nitrite since the denitrification pathways utilized by the N2A2 and N2E2 strains from the Oak Ridge site are predisposed to the accumulation of the toxic nitrite. The use of global isotope metabolomics allowed for this adaptive strategy to be investigated, which would otherwise not have been possible to decipher.
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Affiliation(s)
- Michael E. Kurczy
- Scripps
Center for Metabolomics, The Scripps Research Institute, 10550 North
Torrey Pines Road, La Jolla, California 92037, United States
| | - Erica M. Forsberg
- Scripps
Center for Metabolomics, The Scripps Research Institute, 10550 North
Torrey Pines Road, La Jolla, California 92037, United States
| | - Michael P. Thorgersen
- Department
of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, United States
| | - Farris L. Poole
- Department
of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, United States
| | - H. Paul Benton
- Scripps
Center for Metabolomics, The Scripps Research Institute, 10550 North
Torrey Pines Road, La Jolla, California 92037, United States
| | - Julijana Ivanisevic
- Metabolomics
Platform, Faculty of Biology and Medicine, University of Lausanne, Rue du Bugnon 19, 1011 Lausanne, Switzerland
| | - Minerva L. Tran
- Scripps
Center for Metabolomics, The Scripps Research Institute, 10550 North
Torrey Pines Road, La Jolla, California 92037, United States
| | - Judy D. Wall
- Department
of Biochemistry, University of Missouri, Columbia, Missouri 65211, United States
| | - Dwayne A. Elias
- Biosciences
Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Michael W. W. Adams
- Department
of Biochemistry and Molecular Biology, University of Georgia, Athens, Georgia 30602, United States
| | - Gary Siuzdak
- Scripps
Center for Metabolomics, The Scripps Research Institute, 10550 North
Torrey Pines Road, La Jolla, California 92037, United States
- Departments
of Chemistry, Molecular, and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, United States
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168
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Surrati A, Linforth R, Fisk ID, Sottile V, Kim DH. Non-destructive characterisation of mesenchymal stem cell differentiation using LC-MS-based metabolite footprinting. Analyst 2016; 141:3776-87. [PMID: 27102615 DOI: 10.1039/c6an00170j] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Bone regeneration is a complex biological process where major cellular changes take place to support the osteogenic differentiation of mesenchymal bone progenitors. To characterise these biological changes and better understand the pathways regulating the formation of mature bone cells, the metabolic profile of mesenchymal stem cell (MSC) differentiation in vitro has been assessed non-invasively during osteogenic (OS) treatment using a footprinting technique. Liquid chromatography (LC)-mass spectrometry (MS)-based metabolite profiling of the culture medium was carried out in parallel to mineral deposition and alkaline phosphatase activity which are two hallmarks of osteogenesis in vitro. Metabolic profiles of spent culture media with a combination of univariate and multivariate analyses investigated concentration changes of extracellular metabolites and nutrients linked to the presence of MSCs in culture media. This non-invasive LC-MS-based analytical approach revealed significant metabolic changes between the media from control and OS-treated cells showing distinct effects of MSC differentiation on the environmental footprint of the cells in different conditions (control vs. OS treatment). A subset of compounds was directly linked to the osteogenic time-course of differentiation, and represent interesting metabolite candidates as non-invasive biomarkers for characterising the differentiation of MSCs in a culture medium.
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Affiliation(s)
- Amal Surrati
- Wolfson Centre for Stem Cells, Tissue, Engineering and Modelling (STEM), School of Medicine, The University of Nottingham, CBS Building - University Park, Nottingham NG7 2RD, UK.
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169
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Thompson AP, O'Neill I, Smith EJ, Catchpole J, Fagan A, Burgess KEV, Carmody RJ, Clarke DJ. Glycolysis and pyrimidine biosynthesis are required for replication of adherent-invasive Escherichia coli in macrophages. MICROBIOLOGY-SGM 2016; 162:954-965. [PMID: 27058922 DOI: 10.1099/mic.0.000289] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Adherent-invasive Escherichia coli (AIEC) have been implicated in the aetiology of Crohn's disease (CD), a chronic inflammatory bowel condition. It has been proposed that AIEC-infected macrophages produce high levels of pro-inflammatory cytokines thus contributing to the inflammation observed in CD. AIEC can replicate in macrophages and we wanted to determine if bacterial replication was linked to the high level of cytokine production associated with AIEC-infected macrophages. Therefore, we undertook a genetic analysis of the metabolic requirements for AIEC replication in the macrophage and we show that AIEC replication in this niche is dependent on bacterial glycolysis. In addition, our analyses indicate that AIEC have access to a wide range of nutrients in the macrophage, although the levels of purines and pyrimidines do appear to be limiting. Finally, we show that the macrophage response to AIEC infection is indistinguishable from the response to the non-replicating glycolysis mutant (ΔpfkAB) and a non-pathogenic strain of E. coli, MG1655. Therefore, AIEC does not appear to subvert the normal macrophage response to E. coli during infection.
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Affiliation(s)
- Aoife P Thompson
- School of Microbiology, University College Cork, Cork, Ireland.,APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Ian O'Neill
- School of Microbiology, University College Cork, Cork, Ireland.,APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Emma J Smith
- School of Microbiology, University College Cork, Cork, Ireland.,APC Microbiome Institute, University College Cork, Cork, Ireland
| | - John Catchpole
- School of Microbiology, University College Cork, Cork, Ireland.,APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Ailis Fagan
- APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Karl E V Burgess
- Glasgow Polyomics, University of Glasgow, Switchback Road, Glasgow G61 1QH, UK
| | | | - David J Clarke
- APC Microbiome Institute, University College Cork, Cork, Ireland.,School of Microbiology, University College Cork, Cork, Ireland
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170
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Stipetic LH, Dalby MJ, Davies RL, Morton FR, Ramage G, Burgess KEV. A novel metabolomic approach used for the comparison of Staphylococcus aureus planktonic cells and biofilm samples. Metabolomics 2016; 12:75. [PMID: 27013931 PMCID: PMC4783440 DOI: 10.1007/s11306-016-1002-0] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/16/2015] [Accepted: 01/16/2016] [Indexed: 10/25/2022]
Abstract
INTRODUCTION Bacterial cell characteristics change significantly during differentiation between planktonic and biofilm states. While established methods exist to detect and identify transcriptional and proteomic changes, metabolic fluctuations that distinguish these developmental stages have been less amenable to investigation. OBJECTIVES The objectives of the study were to develop a robust reproducible sample preparation methodology for high throughput biofilm analysis and to determine differences between Staphylococcus aureus in planktonic and biofilm states. METHODS The method uses bead beating in a chloroform/methanol/water extraction solvent to both disrupt cells and quench metabolism. Verification of the method was performed using liquid-chromatography-mass spectrometry. Raw mass-spectrometry data was analysed using an in-house bioinformatics pipe-line incorporating XCMS, MzMatch and in-house R-scripts, with identifications matched to internal standards and metabolite data-base entries. RESULTS We have demonstrated a novel mechanical bead beating method that has been optimised for the extraction of the metabolome from cells of a clinical Staphylococcus aureus strain existing in a planktonic or biofilm state. This high-throughput method is fast and reproducible, allowing for direct comparison between different bacterial growth states. Significant changes in arginine biosynthesis were identified between the two cell populations. CONCLUSIONS The method described herein represents a valuable tool in studying microbial biochemistry at a molecular level. While the methodology is generally applicable to the lysis and extraction of metabolites from Gram positive bacteria, it is particularly applicable to biofilms. Bacteria that exist as a biofilm are shown to be highly distinct metabolically from their 'free living' counterparts, thus highlighting the need to study microbes in different growth states. Metabolomics can successfully distinguish between a planktonic and biofilm growth state. Importantly, this study design, incorporating metabolomics, could be optimised for studying the effects of antimicrobials and drug modes of action, potentially providing explanations and mechanisms of antibiotic resistance and to help devise new antimicrobials.
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Affiliation(s)
- Laurence H. Stipetic
- />Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, The University of Glasgow, Glasgow, UK
- />Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, The University of Glasgow, Garscube Estate, Bearsden, Scotland G61 1QH UK
| | - Matthew J. Dalby
- />Institute of Molecular Cell and Systems Biology, The University of Glasgow, Glasgow, UK
| | - Robert L. Davies
- />Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, The University of Glasgow, Glasgow, UK
| | - Fraser R. Morton
- />Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, The University of Glasgow, Garscube Estate, Bearsden, Scotland G61 1QH UK
| | - Gordon Ramage
- />Infection and Immunity Research Group, Glasgow Dental School, School of Medicine, College of Medical, Veterinary and Life Sciences, The University of Glasgow, Glasgow, UK
| | - Karl E. V. Burgess
- />Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, The University of Glasgow, Glasgow, UK
- />Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, The University of Glasgow, Garscube Estate, Bearsden, Scotland G61 1QH UK
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171
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Metabolomic Profiling of Submaximal Exercise at a Standardised Relative Intensity in Healthy Adults. Metabolites 2016; 6:metabo6010009. [PMID: 26927198 PMCID: PMC4812338 DOI: 10.3390/metabo6010009] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 02/18/2016] [Accepted: 02/22/2016] [Indexed: 01/10/2023] Open
Abstract
Ten physically active subjects underwent two cycling exercise trials. In the first, aerobic capacity (VO2max) was determined and the second was a 45 min submaximal exercise test. Urine samples were collected separately the day before (day 1) , the day of (day 2), and the day after (day 3) the submaximal exercise test (12 samples per subject). Metabolomic profiling of the samples was carried out using hydrophilic interaction chromatography (HILIC) coupled to an Orbitrap Exactive mass spectrometer. Data were extracted, database searched and then subjected to principle components (PCA) and orthogonal partial least squares (OPLSDA) modelling. The best results were obtained from pre-treating the data by normalising the metabolites to their mean output on days 1 and 2 of the trial. This allowed PCA to separate the day 2 first void samples (D2S1) from the day 2 post-exercise samples (D2S3) PCA also separated the equivalent samples obtained on day 1 (D1S1 and D1S3). OPLSDA modelling separated both the D2S1 and D2S3 samples and D1S1 and D1S3 samples. The metabolites affected by the exercise samples included a range of purine metabolites and several acyl carnitines. Some metabolites were subject to diurnal variation these included bile acids and several amino acids, the variation of these metabolites was similar on day 1 and day 2 despite the exercise intervention on day 2. Using OPLS modelling it proved possible to identify a single abundant urinary metabolite provisionally identified as oxo-aminohexanoic acid (OHA) as being strongly correlated with VO2max when the levels in the D2S3 samples were considered.
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172
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Madji Hounoum B, Blasco H, Emond P, Mavel S. Liquid chromatography–high-resolution mass spectrometry-based cell metabolomics: Experimental design, recommendations, and applications. Trends Analyt Chem 2016. [DOI: 10.1016/j.trac.2015.08.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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173
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van der Hooft JJJ, Padmanabhan S, Burgess KEV, Barrett MP. Urinary antihypertensive drug metabolite screening using molecular networking coupled to high-resolution mass spectrometry fragmentation. Metabolomics 2016; 12:125. [PMID: 27471437 PMCID: PMC4932139 DOI: 10.1007/s11306-016-1064-z] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/05/2016] [Accepted: 04/01/2016] [Indexed: 01/01/2023]
Abstract
INTRODUCTION Mass spectrometry is the current technique of choice in studying drug metabolism. High-resolution mass spectrometry in combination with MS/MS gas-phase experiments has the potential to contribute to rapid advances in this field. However, the data emerging from such fragmentation spectral files pose challenges to downstream analysis, given their complexity and size. OBJECTIVES This study aims to detect and visualize antihypertensive drug metabolites in untargeted metabolomics experiments based on the spectral similarity of their fragmentation spectra. Furthermore, spectral clusters of endogenous metabolites were also examined. METHODS Here we apply a molecular networking approach to seek drugs and their metabolites, in fragmentation spectra from urine derived from a cohort of 26 patients on antihypertensive therapy. The mass spectrometry data was collected on a Thermo Q-Exactive coupled to pHILIC chromatography using data dependent analysis (DDA) MS/MS gas-phase experiments. RESULTS In total, 165 separate drug metabolites were found and structurally annotated (17 by spectral matching and 122 by classification based on a clustered fragmentation pattern). The clusters could be traced to 13 drugs including the known antihypertensives verapamil, losartan and amlodipine. The molecular networking approach also generated clusters of endogenous metabolites, including carnitine derivatives, and conjugates containing glutamine, glutamate and trigonelline. CONCLUSIONS The approach offers unprecedented capability in the untargeted identification of drugs and their metabolites at the population level and has great potential to contribute to understanding stratified responses to drugs where differences in drug metabolism may determine treatment outcome.
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Affiliation(s)
| | - Sandosh Padmanabhan
- Institute of Cardiovascular and Medical Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Karl E. V. Burgess
- Glasgow Polyomics, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Michael P. Barrett
- Glasgow Polyomics, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
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174
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Nontarget Analysis of Environmental Samples Based on Liquid Chromatography Coupled to High Resolution Mass Spectrometry (LC-HRMS). APPLICATIONS OF TIME-OF-FLIGHT AND ORBITRAP MASS SPECTROMETRY IN ENVIRONMENTAL, FOOD, DOPING, AND FORENSIC ANALYSIS 2016. [DOI: 10.1016/bs.coac.2016.01.012] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
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175
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Thomas FC, Mudaliar M, Tassi R, McNeilly TN, Burchmore R, Burgess K, Herzyk P, Zadoks RN, Eckersall PD. Mastitomics, the integrated omics of bovine milk in an experimental model of Streptococcus uberis mastitis: 3. Untargeted metabolomics. MOLECULAR BIOSYSTEMS 2016; 12:2762-9. [DOI: 10.1039/c6mb00289g] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Metabolomic investigation of milk from cows with bovine mastitis has revealed major changes in carbohydrates, lipids, amino acids, nucleotides and bile acids.
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Affiliation(s)
- Funmilola Clara Thomas
- Institute of Biodiversity Animal Health and Comparative Medicine
- University of Glasgow
- Glasgow
- UK
| | - Manikhandan Mudaliar
- Institute of Biodiversity Animal Health and Comparative Medicine
- University of Glasgow
- Glasgow
- UK
- Glasgow Polyomics
| | | | | | - Richard Burchmore
- Glasgow Polyomics
- College of Medical
- Veterinary and Life Science
- University of Glasgow
- Glasgow
| | - Karl Burgess
- Glasgow Polyomics
- College of Medical
- Veterinary and Life Science
- University of Glasgow
- Glasgow
| | - Pawel Herzyk
- Glasgow Polyomics
- College of Medical
- Veterinary and Life Science
- University of Glasgow
- Glasgow
| | - Ruth N. Zadoks
- Institute of Biodiversity Animal Health and Comparative Medicine
- University of Glasgow
- Glasgow
- UK
- Moredun Research Institute
| | - P. David Eckersall
- Institute of Biodiversity Animal Health and Comparative Medicine
- University of Glasgow
- Glasgow
- UK
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176
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Atanasov AG, Waltenberger B, Pferschy-Wenzig EM, Linder T, Wawrosch C, Uhrin P, Temml V, Wang L, Schwaiger S, Heiss EH, Rollinger JM, Schuster D, Breuss JM, Bochkov V, Mihovilovic MD, Kopp B, Bauer R, Dirsch VM, Stuppner H. Discovery and resupply of pharmacologically active plant-derived natural products: A review. Biotechnol Adv 2015; 33:1582-1614. [PMID: 26281720 PMCID: PMC4748402 DOI: 10.1016/j.biotechadv.2015.08.001] [Citation(s) in RCA: 1325] [Impact Index Per Article: 147.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2015] [Revised: 07/16/2015] [Accepted: 08/07/2015] [Indexed: 01/01/2023]
Abstract
Medicinal plants have historically proven their value as a source of molecules with therapeutic potential, and nowadays still represent an important pool for the identification of novel drug leads. In the past decades, pharmaceutical industry focused mainly on libraries of synthetic compounds as drug discovery source. They are comparably easy to produce and resupply, and demonstrate good compatibility with established high throughput screening (HTS) platforms. However, at the same time there has been a declining trend in the number of new drugs reaching the market, raising renewed scientific interest in drug discovery from natural sources, despite of its known challenges. In this survey, a brief outline of historical development is provided together with a comprehensive overview of used approaches and recent developments relevant to plant-derived natural product drug discovery. Associated challenges and major strengths of natural product-based drug discovery are critically discussed. A snapshot of the advanced plant-derived natural products that are currently in actively recruiting clinical trials is also presented. Importantly, the transition of a natural compound from a "screening hit" through a "drug lead" to a "marketed drug" is associated with increasingly challenging demands for compound amount, which often cannot be met by re-isolation from the respective plant sources. In this regard, existing alternatives for resupply are also discussed, including different biotechnology approaches and total organic synthesis. While the intrinsic complexity of natural product-based drug discovery necessitates highly integrated interdisciplinary approaches, the reviewed scientific developments, recent technological advances, and research trends clearly indicate that natural products will be among the most important sources of new drugs also in the future.
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Affiliation(s)
- Atanas G. Atanasov
- Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Birgit Waltenberger
- Institute of Pharmacy/Pharmacognosy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Eva-Maria Pferschy-Wenzig
- Institute of Pharmaceutical Sciences, Department of Pharmacognosy, University of Graz, Universitätsplatz 4/I, 8010 Graz, Austria
| | - Thomas Linder
- Institute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9/163-OC, 1060 Vienna, Austria
| | - Christoph Wawrosch
- Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Pavel Uhrin
- Institute of Vascular Biology and Thrombosis Research, Center of Physiology and Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Veronika Temml
- Institute of Pharmacy/Pharmaceutical Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Limei Wang
- Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Stefan Schwaiger
- Institute of Pharmacy/Pharmacognosy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Elke H. Heiss
- Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Judith M. Rollinger
- Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
- Institute of Pharmacy/Pharmacognosy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Daniela Schuster
- Institute of Pharmacy/Pharmaceutical Chemistry and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
| | - Johannes M. Breuss
- Institute of Vascular Biology and Thrombosis Research, Center of Physiology and Pharmacology, Medical University of Vienna, 1090 Vienna, Austria
| | - Valery Bochkov
- Institute of Pharmaceutical Sciences, Department of Pharmaceutical Chemistry, University of Graz, Humboldtstrasse 46/III, 8010 Graz, Austria
| | - Marko D. Mihovilovic
- Institute of Applied Synthetic Chemistry, Vienna University of Technology, Getreidemarkt 9/163-OC, 1060 Vienna, Austria
| | - Brigitte Kopp
- Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Rudolf Bauer
- Institute of Pharmaceutical Sciences, Department of Pharmacognosy, University of Graz, Universitätsplatz 4/I, 8010 Graz, Austria
| | - Verena M. Dirsch
- Department of Pharmacognosy, University of Vienna, Althanstrasse 14, 1090 Vienna, Austria
| | - Hermann Stuppner
- Institute of Pharmacy/Pharmacognosy and Center for Molecular Biosciences Innsbruck (CMBI), University of Innsbruck, Innrain 80-82, 6020 Innsbruck, Austria
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177
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Hao L, Zhong X, Greer T, Ye H, Li L. Relative quantification of amine-containing metabolites using isobaric N,N-dimethyl leucine (DiLeu) reagents via LC-ESI-MS/MS and CE-ESI-MS/MS. Analyst 2015; 140:467-75. [PMID: 25429371 DOI: 10.1039/c4an01582g] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Tandem mass spectrometry (MS/MS)-based relative quantification by isobaric labeling is a useful technique to compare different metabolic expression levels in biological systems. For the first time, we have labeled primary and secondary amine-containing small molecules using 4-plex isobaric N,N-dimethyl leucine (DiLeu) to perform relative quantification. Good labeling efficiency and quantification accuracy were demonstrated with a mixture of 12 metabolite standards including amino acids and small molecule neurotransmitters. Labeling amine-containing metabolites with DiLeu reagents also enabled the separation of polar metabolites by nanoRPLC and improved the detection sensitivity by CE-ESI-MS. The 4-plex DiLeu labeling technique combined with LC-MS/MS and CE-MS/MS platforms were applied to profile and quantify amine-containing metabolites in mouse urine. The variability of concentrations of identified metabolites in urine samples from different mouse individuals was illustrated by the ratios of reporter ion intensities acquired from online data-dependent analysis.
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Affiliation(s)
- Ling Hao
- School of Pharmacy, University of Wisconsin-Madison, 777 Highland Avenue, Madison, WI 53705, USA.
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178
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Gutarowska B, Celikkol-Aydin S, Bonifay V, Otlewska A, Aydin E, Oldham AL, Brauer JI, Duncan KE, Adamiak J, Sunner JA, Beech IB. Metabolomic and high-throughput sequencing analysis-modern approach for the assessment of biodeterioration of materials from historic buildings. Front Microbiol 2015; 6:979. [PMID: 26483760 PMCID: PMC4586457 DOI: 10.3389/fmicb.2015.00979] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2015] [Accepted: 09/03/2015] [Indexed: 11/29/2022] Open
Abstract
Preservation of cultural heritage is of paramount importance worldwide. Microbial colonization of construction materials, such as wood, brick, mortar, and stone in historic buildings can lead to severe deterioration. The aim of the present study was to give modern insight into the phylogenetic diversity and activated metabolic pathways of microbial communities colonized historic objects located in the former Auschwitz II–Birkenau concentration and extermination camp in Oświecim, Poland. For this purpose we combined molecular, microscopic and chemical methods. Selected specimens were examined using Field Emission Scanning Electron Microscopy (FESEM), metabolomic analysis and high-throughput Illumina sequencing. FESEM imaging revealed the presence of complex microbial communities comprising diatoms, fungi and bacteria, mainly cyanobacteria and actinobacteria, on sample surfaces. Microbial diversity of brick specimens appeared higher than that of the wood and was dominated by algae and cyanobacteria, while wood was mainly colonized by fungi. DNA sequences documented the presence of 15 bacterial phyla representing 99 genera including Halomonas, Halorhodospira, Salinisphaera, Salinibacterium, Rubrobacter, Streptomyces, Arthrobacter and nine fungal classes represented by 113 genera including Cladosporium, Acremonium, Alternaria, Engyodontium, Penicillium, Rhizopus, and Aureobasidium. Most of the identified sequences were characteristic of organisms implicated in deterioration of wood and brick. Metabolomic data indicated the activation of numerous metabolic pathways, including those regulating the production of primary and secondary metabolites, for example, metabolites associated with the production of antibiotics, organic acids and deterioration of organic compounds. The study demonstrated that a combination of electron microscopy imaging with metabolomic and genomic techniques allows to link the phylogenetic information and metabolic profiles of microbial communities and to shed new light on biodeterioration processes.
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Affiliation(s)
- Beata Gutarowska
- Department of Biotechnology and Food Sciences, Institute of Fermentation Technology and Microbiology, Lodz University of Technology Lodz, Poland
| | | | - Vincent Bonifay
- Department of Microbiology and Plant Biology, University of Oklahoma Norman, OK, USA
| | - Anna Otlewska
- Department of Biotechnology and Food Sciences, Institute of Fermentation Technology and Microbiology, Lodz University of Technology Lodz, Poland
| | - Egemen Aydin
- Department of Microbiology and Plant Biology, University of Oklahoma Norman, OK, USA
| | - Athenia L Oldham
- Department of Microbiology and Plant Biology, University of Oklahoma Norman, OK, USA
| | - Jonathan I Brauer
- Department of Microbiology and Plant Biology, University of Oklahoma Norman, OK, USA
| | - Kathleen E Duncan
- Department of Microbiology and Plant Biology, University of Oklahoma Norman, OK, USA
| | - Justyna Adamiak
- Department of Biotechnology and Food Sciences, Institute of Fermentation Technology and Microbiology, Lodz University of Technology Lodz, Poland
| | - Jan A Sunner
- Department of Microbiology and Plant Biology, University of Oklahoma Norman, OK, USA
| | - Iwona B Beech
- Department of Microbiology and Plant Biology, University of Oklahoma Norman, OK, USA
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179
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Westrop GD, Williams RAM, Wang L, Zhang T, Watson DG, Silva AM, Coombs GH. Metabolomic Analyses of Leishmania Reveal Multiple Species Differences and Large Differences in Amino Acid Metabolism. PLoS One 2015; 10:e0136891. [PMID: 26368322 PMCID: PMC4569581 DOI: 10.1371/journal.pone.0136891] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/18/2015] [Accepted: 08/09/2015] [Indexed: 01/09/2023] Open
Abstract
Comparative genomic analyses of Leishmania species have revealed relatively minor heterogeneity amongst recognised housekeeping genes and yet the species cause distinct infections and pathogenesis in their mammalian hosts. To gain greater information on the biochemical variation between species, and insights into possible metabolic mechanisms underpinning visceral and cutaneous leishmaniasis, we have undertaken in this study a comparative analysis of the metabolomes of promastigotes of L. donovani, L. major and L. mexicana. The analysis revealed 64 metabolites with confirmed identity differing 3-fold or more between the cell extracts of species, with 161 putatively identified metabolites differing similarly. Analysis of the media from cultures revealed an at least 3-fold difference in use or excretion of 43 metabolites of confirmed identity and 87 putatively identified metabolites that differed to a similar extent. Strikingly large differences were detected in their extent of amino acid use and metabolism, especially for tryptophan, aspartate, arginine and proline. Major pathways of tryptophan and arginine catabolism were shown to be to indole-3-lactate and arginic acid, respectively, which were excreted. The data presented provide clear evidence on the value of global metabolomic analyses in detecting species-specific metabolic features, thus application of this technology should be a major contributor to gaining greater understanding of how pathogens are adapted to infecting their hosts.
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Affiliation(s)
- Gareth D. Westrop
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
| | - Roderick A. M. Williams
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
- Institute of Biomedical and Environmental Health Research, University of the West of Scotland, Paisley, United Kingdom
| | - Lijie Wang
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
| | - Tong Zhang
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
| | - David G. Watson
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
| | - Ana Marta Silva
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
- Instituto de Biologia Molecular e Celular, Universidade do Porto, Porto, Portugal
| | - Graham H. Coombs
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
- * E-mail:
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180
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Huan T, Wu Y, Tang C, Lin G, Li L. DnsID in MyCompoundID for rapid identification of dansylated amine- and phenol-containing metabolites in LC-MS-based metabolomics. Anal Chem 2015; 87:9838-45. [PMID: 26327437 DOI: 10.1021/acs.analchem.5b02282] [Citation(s) in RCA: 89] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
High-performance chemical isotope labeling (CIL) liquid chromatography-mass spectrometry (LC-MS) is an enabling technology based on rational design of labeling reagents to target a class of metabolites sharing the same functional group (e.g., all the amine-containing metabolites or the amine submetabolome) to provide concomitant improvements in metabolite separation, detection, and quantification. However, identification of labeled metabolites remains to be an analytical challenge. In this work, we describe a library of labeled standards and a search method for metabolite identification in CIL LC-MS. The current library consists of 273 unique metabolites, mainly amines and phenols that are individually labeled by dansylation (Dns). Some of them produced more than one Dns-derivative (isomers or multiple labeled products), resulting in a total of 315 dansyl compounds in the library. These metabolites cover 42 metabolic pathways, allowing the possibility of probing their changes in metabolomics studies. Each labeled metabolite contains three searchable parameters: molecular ion mass, MS/MS spectrum, and retention time (RT). To overcome RT variations caused by experimental conditions used, we have developed a calibration method to normalize RTs of labeled metabolites using a mixture of RT calibrants. A search program, DnsID, has been developed in www.MyCompoundID.org for automated identification of dansyl labeled metabolites in a sample based on matching one or more of the three parameters with those of the library standards. Using human urine as an example, we illustrate the workflow and analytical performance of this method for metabolite identification. This freely accessible resource is expandable by adding more amine and phenol standards in the future. In addition, the same strategy should be applicable for developing other labeled standards libraries to cover different classes of metabolites for comprehensive metabolomics using CIL LC-MS.
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Affiliation(s)
- Tao Huan
- Departments of Chemistry and ‡Computing Science, University of Alberta , Edmonton, Alberta T6G2G2, Canada
| | - Yiman Wu
- Departments of Chemistry and ‡Computing Science, University of Alberta , Edmonton, Alberta T6G2G2, Canada
| | - Chenqu Tang
- Departments of Chemistry and ‡Computing Science, University of Alberta , Edmonton, Alberta T6G2G2, Canada
| | - Guohui Lin
- Departments of Chemistry and ‡Computing Science, University of Alberta , Edmonton, Alberta T6G2G2, Canada
| | - Liang Li
- Departments of Chemistry and ‡Computing Science, University of Alberta , Edmonton, Alberta T6G2G2, Canada
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181
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Knolhoff AM, Croley TR. Non-targeted screening approaches for contaminants and adulterants in food using liquid chromatography hyphenated to high resolution mass spectrometry. J Chromatogr A 2015; 1428:86-96. [PMID: 26372444 DOI: 10.1016/j.chroma.2015.08.059] [Citation(s) in RCA: 84] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 08/14/2015] [Accepted: 08/27/2015] [Indexed: 12/22/2022]
Abstract
The majority of analytical methods for food safety monitor the presence of a specific compound or defined set of compounds. Non-targeted screening methods are complementary to these approaches by detecting and identifying unexpected compounds present in food matrices that may be harmful to public health. However, the development and implementation of generalized non-targeted screening workflows are particularly challenging, especially for food matrices due to inherent sample complexity and diversity and a large analyte concentration range. One approach that can be implemented is liquid chromatography coupled to high-resolution mass spectrometry, which serves to reduce this complexity and is capable of generating molecular formulae for compounds of interest. Current capabilities, strategies, and challenges will be reviewed for sample preparation, mass spectrometry, chromatography, and data processing workflows. Considerations to increase the accuracy and speed of identifying unknown molecular species will also be addressed, including suggestions for achieving sufficient data quality for non-targeted screening applications.
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Affiliation(s)
- Ann M Knolhoff
- U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, 5100 Paint Branch Parkway, College Park, MD 20740, United States.
| | - Timothy R Croley
- U.S. Food and Drug Administration, Center for Food Safety and Applied Nutrition, 5100 Paint Branch Parkway, College Park, MD 20740, United States
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182
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Stanstrup J, Neumann S, Vrhovšek U. PredRet: prediction of retention time by direct mapping between multiple chromatographic systems. Anal Chem 2015; 87:9421-8. [PMID: 26289378 DOI: 10.1021/acs.analchem.5b02287] [Citation(s) in RCA: 108] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Demands in research investigating small molecules by applying untargeted approaches have been a key motivator for the development of repositories for mass spectrometry spectra and automated tools to aid compound identification. Comparatively little attention has been afforded to using retention times (RTs) to distinguish compounds and for liquid chromatography there are currently no coordinated efforts to share and exploit RT information. We therefore present PredRet; the first tool that makes community sharing of RT information possible across laboratories and chromatographic systems (CSs). At http://predret.org , a database of RTs from different CSs is available and users can upload their own experimental RTs and download predicted RTs for compounds which they have not experimentally determined in their own experiments. For each possible pair of CSs in the database, the RTs are used to construct a projection model between the RTs in the two CSs. The number of compounds for which RTs can be predicted and the accuracy of the predictions are dependent upon the compound coverage overlap between the CSs used for construction of projection models. At the moment, it is possible to predict up to 400 RTs with a median error between 0.01 and 0.28 min depending on the CS and the median width of the prediction interval ranging from 0.08 to 1.86 min. By comparing experimental and predicted RTs, the user can thus prioritize which isomers to target for further characterization and potentially exclude some structures completely. As the database grows, the number and accuracy of predictions will increase.
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Affiliation(s)
- Jan Stanstrup
- Department of Food Quality and Nutrition, Research and Innovation Centre, Fondazione Edmund Mach (FEM) , Via E. Mach 1, 38010 San Michele all'Adige, Trentiono, Italy
| | - Steffen Neumann
- Department of Stress and Developmental Biology, Leibniz Institute of Plant Biochemistry , Weinberg 3, 06120 Halle, Germany
| | - Urška Vrhovšek
- Department of Food Quality and Nutrition, Research and Innovation Centre, Fondazione Edmund Mach (FEM) , Via E. Mach 1, 38010 San Michele all'Adige, Trentiono, Italy
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183
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Computational analysis and ratiometric comparison approaches aimed to assist column selection in hydrophilic interaction liquid chromatography–tandem mass spectrometry targeted metabolomics. J Chromatogr A 2015; 1406:145-55. [DOI: 10.1016/j.chroma.2015.06.008] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2015] [Revised: 06/01/2015] [Accepted: 06/05/2015] [Indexed: 12/27/2022]
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184
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Aicheler F, Li J, Hoene M, Lehmann R, Xu G, Kohlbacher O. Retention Time Prediction Improves Identification in Nontargeted Lipidomics Approaches. Anal Chem 2015; 87:7698-704. [PMID: 26145158 DOI: 10.1021/acs.analchem.5b01139] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Identification of lipids in nontargeted lipidomics based on liquid-chromatography coupled to mass spectrometry (LC-MS) is still a major issue. While both accurate mass and fragment spectra contain valuable information, retention time (tR) information can be used to augment this data. We present a retention time model based on machine learning approaches which enables an improved assignment of lipid structures and automated annotation of lipidomics data. In contrast to common approaches we used a complex mixture of 201 lipids originating from fat tissue instead of a standard mixture to train a support vector regression (SVR) model including molecular structural features. The cross-validated model achieves a correlation coefficient between predicted and experimental test sample retention times of r = 0.989. Combining our retention time model with identification via accurate mass search (AMS) of lipids against the comprehensive LIPID MAPS database, retention time filtering can significantly reduce the rate of false positives in complex data sets like adipose tissue extracts. In our case, filtering with retention time information removed more than half of the potential identifications, while retaining 95% of the correct identifications. Combination of high-precision retention time prediction and accurate mass can thus significantly narrow down the number of hypotheses to be assessed for lipid identification in complex lipid pattern like tissue profiles.
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Affiliation(s)
- Fabian Aicheler
- †Applied Bioinformatics, Center for Bioinformatics, Quantitative Biology Center, and Department of Computer Science, University of Tuebingen, Sand 14, 72076 Tuebingen, Baden-Württemberg, Germany
| | - Jia Li
- ‡Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China
| | - Miriam Hoene
- §Division of Clinical Chemistry and Pathobiochemistry, Department of Internal Medicine IV, University Hospital Tuebingen, 72076 Tuebingen, Baden-Württemberg, Germany
| | - Rainer Lehmann
- §Division of Clinical Chemistry and Pathobiochemistry, Department of Internal Medicine IV, University Hospital Tuebingen, 72076 Tuebingen, Baden-Württemberg, Germany.,∥Department of Molecular Diabetology, Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Centre Munich at the University of Tuebingen, 72076 Tuebingen, Baden-Württemberg, Germany.,⊥German Center for Diabetes Research (DZD), 72076 Tuebingen, Baden-Württemberg, Germany
| | - Guowang Xu
- ‡Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, China
| | - Oliver Kohlbacher
- †Applied Bioinformatics, Center for Bioinformatics, Quantitative Biology Center, and Department of Computer Science, University of Tuebingen, Sand 14, 72076 Tuebingen, Baden-Württemberg, Germany.,∥Department of Molecular Diabetology, Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Centre Munich at the University of Tuebingen, 72076 Tuebingen, Baden-Württemberg, Germany.,⊥German Center for Diabetes Research (DZD), 72076 Tuebingen, Baden-Württemberg, Germany
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185
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de Macêdo JP, Schumann Burkard G, Niemann M, Barrett MP, Vial H, Mäser P, Roditi I, Schneider A, Bütikofer P. An Atypical Mitochondrial Carrier That Mediates Drug Action in Trypanosoma brucei. PLoS Pathog 2015; 11:e1004875. [PMID: 25946070 PMCID: PMC4422618 DOI: 10.1371/journal.ppat.1004875] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2014] [Accepted: 04/13/2015] [Indexed: 01/27/2023] Open
Abstract
Elucidating the mechanism of action of trypanocidal compounds is an important step in the development of more efficient drugs against Trypanosoma brucei. In a screening approach using an RNAi library in T. brucei bloodstream forms, we identified a member of the mitochondrial carrier family, TbMCP14, as a prime candidate mediating the action of a group of anti-parasitic choline analogs. Depletion of TbMCP14 by inducible RNAi in both bloodstream and procyclic forms increased resistance of parasites towards the compounds by 7-fold and 3-fold, respectively, compared to uninduced cells. In addition, down-regulation of TbMCP14 protected bloodstream form mitochondria from a drug-induced decrease in mitochondrial membrane potential. Conversely, over-expression of the carrier in procyclic forms increased parasite susceptibility more than 13-fold. Metabolomic analyses of parasites over-expressing TbMCP14 showed increased levels of the proline metabolite, pyrroline-5-carboxylate, suggesting a possible involvement of TbMCP14 in energy production. The generation of TbMCP14 knock-out parasites showed that the carrier is not essential for survival of T. brucei bloodstream forms, but reduced parasite proliferation under standard culture conditions. In contrast, depletion of TbMCP14 in procyclic forms resulted in growth arrest, followed by parasite death. The time point at which parasite proliferation stopped was dependent on the major energy source, i.e. glucose versus proline, in the culture medium. Together with our findings that proline-dependent ATP production in crude mitochondria from TbMCP14-depleted trypanosomes was reduced compared to control mitochondria, the study demonstrates that TbMCP14 is involved in energy production in T. brucei. Since TbMCP14 belongs to a trypanosomatid-specific clade of mitochondrial carrier family proteins showing very poor similarity to mitochondrial carriers of mammals, it may represent an interesting target for drug action or targeting. Human and animal trypanosomiases caused by Trypanosoma brucei parasites represent major burdens to human welfare and agricultural development in rural sub-Saharan Africa. Although the numbers of infected humans have decreased continuously during the last decades, emerging resistance and adverse side effects against commonly used drugs require an urgent need for the identification of novel drug targets and the development of new drugs. Using an unbiased genome-wide screen to search for genes involved in the mode of action of trypanocidal compounds, we identified a member of the mitochondrial carrier family, TbMCP14, as prime candidate to mediate the action of a group of anti-parasitic choline analogs against T. brucei. Ablation of TbMCP14 expression by RNA interference or gene deletion decreases the susceptibility of parasites towards the compounds while over-expression of the carrier shows the opposite effect. In addition, down-regulation of TbMCP14 protects mitochondria from drug-induced decrease in mitochondrial membrane potential and reduces proline-dependent ATP production. Together, the results demonstrate that TbMCP14 is involved in energy production in T. brucei, possibly by acting as a mitochondrial proline carrier, and reveal TbMCP14 as candidate protein for drug action or targeting.
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Affiliation(s)
- Juan P de Macêdo
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland; Graduate School for Cellular and Biomedical Sciences, University of Bern, Bern, Switzerland
| | | | - Moritz Niemann
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Michael P Barrett
- Wellcome Trust Centre for Molecular Parasitology, Institute of Infection, Immunity and Inflammation, and Glasgow Polyomics, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Henri Vial
- Dynamique Moléculaire des Interactions Membranaires, CNRS UMR 5235, Université Montpellier II, Montpellier, France
| | - Pascal Mäser
- Swiss Tropical and Public Health Institute, Basel, Switzerland; University of Basel, Basel, Switzerland
| | - Isabel Roditi
- Institute of Cell Biology, University of Bern, Bern, Switzerland
| | - André Schneider
- Department of Chemistry and Biochemistry, University of Bern, Bern, Switzerland
| | - Peter Bütikofer
- Institute of Biochemistry and Molecular Medicine, University of Bern, Bern, Switzerland
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186
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Xia Z, Cai W, Shao X. Predicting chromatographic retention time of C10-chlorinated paraffins in gas chromatography-mass spectrometry using quantitative structure retention relationship. Chem Res Chin Univ 2015. [DOI: 10.1007/s40242-015-4366-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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187
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Contrepois K, Jiang L, Snyder M. Optimized Analytical Procedures for the Untargeted Metabolomic Profiling of Human Urine and Plasma by Combining Hydrophilic Interaction (HILIC) and Reverse-Phase Liquid Chromatography (RPLC)-Mass Spectrometry. Mol Cell Proteomics 2015; 14:1684-95. [PMID: 25787789 PMCID: PMC4458729 DOI: 10.1074/mcp.m114.046508] [Citation(s) in RCA: 158] [Impact Index Per Article: 17.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2014] [Indexed: 12/01/2022] Open
Abstract
Profiling of body fluids is crucial for monitoring and discovering metabolic markers of health and disease and for providing insights into human physiology. Since human urine and plasma each contain an extreme diversity of metabolites, a single liquid chromatographic system when coupled to mass spectrometry (MS) is not sufficient to achieve reasonable metabolome coverage. Hydrophilic interaction liquid chromatography (HILIC) offers complementary information to reverse-phase liquid chromatography (RPLC) by retaining polar metabolites. With the objective of finding the optimal combined chromatographic solution to profile urine and plasma, we systematically investigated the performance of five HILIC columns with different chemistries operated at three different pH (acidic, neutral, basic) and five C18-silica RPLC columns. The zwitterionic column ZIC-HILIC operated at neutral pH provided optimal performance on a large set of hydrophilic metabolites. The RPLC columns Hypersil GOLD and Zorbax SB aq were proven to be best suited for the metabolic profiling of urine and plasma, respectively. Importantly, the optimized HILIC-MS method showed excellent intrabatch peak area reproducibility (CV < 12%) and good long-term interbatch (40 days) peak area reproducibility (CV < 22%) that were similar to those of RPLC-MS procedures. Finally, combining the optimal HILIC- and RPLC-MS approaches greatly expanded metabolome coverage with 44% and 108% new metabolic features detected compared with RPLC-MS alone for urine and plasma, respectively. The proposed combined LC-MS approaches improve the comprehensiveness of global metabolic profiling of body fluids and thus are valuable for monitoring and discovering metabolic changes associated with health and disease in clinical research studies.
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Affiliation(s)
- Kévin Contrepois
- From the Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Lihua Jiang
- From the Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
| | - Michael Snyder
- From the Department of Genetics, Stanford University School of Medicine, Stanford, CA, USA
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188
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Connolly JPR, Goldstone RJ, Burgess K, Cogdell RJ, Beatson SA, Vollmer W, Smith DGE, Roe AJ. The host metabolite D-serine contributes to bacterial niche specificity through gene selection. ISME JOURNAL 2015; 9:1039-51. [PMID: 25526369 PMCID: PMC4366372 DOI: 10.1038/ismej.2014.242] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Revised: 10/07/2014] [Accepted: 11/13/2014] [Indexed: 01/29/2023]
Abstract
Escherichia coli comprise a diverse array of both commensals and niche-specific pathotypes. The ability to cause disease results from both carriage of specific virulence factors and regulatory control of these via environmental stimuli. Moreover, host metabolites further refine the response of bacteria to their environment and can dramatically affect the outcome of the host-pathogen interaction. Here, we demonstrate that the host metabolite, D-serine, selectively affects gene expression in E. coli O157:H7. Transcriptomic profiling showed exposure to D-serine results in activation of the SOS response and suppresses expression of the Type 3 Secretion System (T3SS) used to attach to host cells. We also show that concurrent carriage of both the D-serine tolerance locus (dsdCXA) and the locus of enterocyte effacement pathogenicity island encoding a T3SS is extremely rare, a genotype that we attribute to an 'evolutionary incompatibility' between the two loci. This study demonstrates the importance of co-operation between both core and pathogenic genetic elements in defining niche specificity.
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Affiliation(s)
- James P R Connolly
- 1] Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK [2] School of Life Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Robert J Goldstone
- 1] Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK [2] School of Life Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Karl Burgess
- 1] Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK [2] School of Life Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
| | - Richard J Cogdell
- Institute of Molecular Cell and Systems Biology, University of Glasgow, Glasgow, UK
| | - Scott A Beatson
- School of Chemistry and Molecular Biosciences and Australian Infectious Diseases Research Centre, University of Queensland, St Lucia, Queensland, Australia
| | - Waldemar Vollmer
- Centre for Bacterial Cell Biology, Institute for Cell and Molecular Biosciences, Newcastle University, Newcastle upon Tyne, UK
| | - David G E Smith
- 1] Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK [2] School of Life Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK [3] Moredun Research Institute, Pentlands Science Park, Bush Loan, Edinburgh, Midlothian, UK
| | - Andrew J Roe
- 1] Institute of Infection, Immunity and Inflammation, University of Glasgow, Glasgow, UK [2] School of Life Sciences, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, UK
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189
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Creek DJ, Mazet M, Achcar F, Anderson J, Kim DH, Kamour R, Morand P, Millerioux Y, Biran M, Kerkhoven EJ, Chokkathukalam A, Weidt SK, Burgess KEV, Breitling R, Watson DG, Bringaud F, Barrett MP. Probing the metabolic network in bloodstream-form Trypanosoma brucei using untargeted metabolomics with stable isotope labelled glucose. PLoS Pathog 2015; 11:e1004689. [PMID: 25775470 PMCID: PMC4361558 DOI: 10.1371/journal.ppat.1004689] [Citation(s) in RCA: 92] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2014] [Accepted: 01/19/2015] [Indexed: 01/21/2023] Open
Abstract
Metabolomics coupled with heavy-atom isotope-labelled glucose has been used to probe the metabolic pathways active in cultured bloodstream form trypomastigotes of Trypanosoma brucei, a parasite responsible for human African trypanosomiasis. Glucose enters many branches of metabolism beyond glycolysis, which has been widely held to be the sole route of glucose metabolism. Whilst pyruvate is the major end-product of glucose catabolism, its transamination product, alanine, is also produced in significant quantities. The oxidative branch of the pentose phosphate pathway is operative, although the non-oxidative branch is not. Ribose 5-phosphate generated through this pathway distributes widely into nucleotide synthesis and other branches of metabolism. Acetate, derived from glucose, is found associated with a range of acetylated amino acids and, to a lesser extent, fatty acids; while labelled glycerol is found in many glycerophospholipids. Glucose also enters inositol and several sugar nucleotides that serve as precursors to macromolecule biosynthesis. Although a Krebs cycle is not operative, malate, fumarate and succinate, primarily labelled in three carbons, were present, indicating an origin from phosphoenolpyruvate via oxaloacetate. Interestingly, the enzyme responsible for conversion of phosphoenolpyruvate to oxaloacetate, phosphoenolpyruvate carboxykinase, was shown to be essential to the bloodstream form trypanosomes, as demonstrated by the lethal phenotype induced by RNAi-mediated downregulation of its expression. In addition, glucose derivatives enter pyrimidine biosynthesis via oxaloacetate as a precursor to aspartate and orotate. In this work we have followed the distribution of carbon derived from glucose in bloodstream form trypanosomes, the causative agent of African trypanosomiasis, revealing it to enter a diverse range of metabolites. The work involved using 13C-labelled glucose and following the fate of the labelled carbon with an LC-MS based metabolomics platform. Beyond glycolysis and the oxidative branch of the pentose phosphate pathway the label entered lipid biosynthesis both through glycerol 3-phosphate and also acetate. Glucose derived carbon also entered nucleotide synthesis through ribose and pyrimidine synthesis through oxaloacetate-derived aspartate. Appreciable quantities of the carboxylic acids succinate and malate were identified, although labelling patterns indicate they are not TCA cycle derived. Amino sugars and sugar nucleotides were also labelled as was inositol used in protein modification but not in inositol phospholipid headgroup production. We confirm active and essential oxaloacetate production in bloodstream form trypanosomes and show that phosphoenolpyruvate carboxykinase is essential to these parasites using RNA interference. The amount of glucose entering these metabolites is minor compared to the quantity that enters pyruvate excreted from the cell, but the observation that enzymes contributing to the metabolism of glucose beyond glycolysis can be essential offers potential new targets for chemotherapy against trypanosomiasis.
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Affiliation(s)
- Darren J. Creek
- Drug Delivery, Disposition and Dynamics, Monash Institute of Pharmaceutical Sciences, Monash University, Parkville Campus, Parkville, Victoria, Australia
| | - Muriel Mazet
- Centre de Résonance Magnétique des Systèmes Biologiques, Université de Bordeaux, CNRS UMR-5536, Bordeaux, France
| | - Fiona Achcar
- Wellcome Trust Centre of Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Jana Anderson
- Department of Public Health, Institute of Health and Wellbeing, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Dong-Hyun Kim
- Centre for Analytical Bioscience, School of Pharmacy, University of Nottingham, University Park, Nottingham, United Kingdom
| | - Ruwida Kamour
- Department of Medicinal and Pharmaceutical Chemistry, Faculty of Pharmacy, University of Tripoli, Tripoli, Libya
| | - Pauline Morand
- Centre de Résonance Magnétique des Systèmes Biologiques, Université de Bordeaux, CNRS UMR-5536, Bordeaux, France
| | - Yoann Millerioux
- Centre de Résonance Magnétique des Systèmes Biologiques, Université de Bordeaux, CNRS UMR-5536, Bordeaux, France
| | - Marc Biran
- Centre de Résonance Magnétique des Systèmes Biologiques, Université de Bordeaux, CNRS UMR-5536, Bordeaux, France
| | - Eduard J. Kerkhoven
- Systems and Synthetic Biology, Department of Chemical and Biological Engineering, Chalmers University of Technology, Göteborg, Sweden
| | - Achuthanunni Chokkathukalam
- Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, Garscube Campus, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Stefan K. Weidt
- Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, Garscube Campus, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Karl E. V. Burgess
- Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, Garscube Campus, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, United Kingdom
| | - Rainer Breitling
- Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, Manchester, United Kingdom
| | - David G. Watson
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, United Kingdom
| | - Frédéric Bringaud
- Centre de Résonance Magnétique des Systèmes Biologiques, Université de Bordeaux, CNRS UMR-5536, Bordeaux, France
| | - Michael P. Barrett
- Wellcome Trust Centre of Molecular Parasitology, Institute of Infection, Immunity and Inflammation, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, United Kingdom
- Glasgow Polyomics, Wolfson Wohl Cancer Research Centre, Garscube Campus, College of Medical Veterinary & Life Sciences, University of Glasgow, Glasgow, United Kingdom
- * E-mail:
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190
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van der Hooft JJJ, Ridder L, Barrett MP, Burgess KEV. Enhanced acylcarnitine annotation in high-resolution mass spectrometry data: fragmentation analysis for the classification and annotation of acylcarnitines. Front Bioeng Biotechnol 2015; 3:26. [PMID: 25806366 PMCID: PMC4353373 DOI: 10.3389/fbioe.2015.00026] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2014] [Accepted: 02/19/2015] [Indexed: 11/24/2022] Open
Abstract
Metabolite annotation and identification are primary challenges in untargeted metabolomics experiments. Rigorous workflows for reliable annotation of mass features with chemical structures or compound classes are needed to enhance the power of untargeted mass spectrometry. High-resolution mass spectrometry considerably improves the confidence in assigning elemental formulas to mass features in comparison to nominal mass spectrometry, and embedding of fragmentation methods enables more reliable metabolite annotations and facilitates metabolite classification. However, the analysis of mass fragmentation spectra can be a time-consuming step and requires expert knowledge. This study demonstrates how characteristic fragmentations, specific to compound classes, can be used to systematically analyze their presence in complex biological extracts like urine that have undergone untargeted mass spectrometry combined with data dependent or targeted fragmentation. Human urine extracts were analyzed using normal phase liquid chromatography (hydrophilic interaction chromatography) coupled to an Ion Trap-Orbitrap hybrid instrument. Subsequently, mass chromatograms and collision-induced dissociation and higher-energy collisional dissociation (HCD) fragments were annotated using the freely available MAGMa software1. Acylcarnitines play a central role in energy metabolism by transporting fatty acids into the mitochondrial matrix. By filtering on a combination of a mass fragment and neutral loss designed based on the MAGMa fragment annotations, we were able to classify and annotate 50 acylcarnitines in human urine extracts, based on high-resolution mass spectrometry HCD fragmentation spectra at different energies for all of them. Of these annotated acylcarnitines, 31 are not described in HMDB yet and for only 4 annotated acylcarnitines the fragmentation spectra could be matched to reference spectra. Therefore, we conclude that the use of mass fragmentation filters within the context of untargeted metabolomics experiments is a valuable tool to enhance the annotation of small metabolites.
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Affiliation(s)
| | - Lars Ridder
- Laboratory of Biochemistry, Wageningen University and Research Centre , Wageningen , Netherlands
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191
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Fasoula S, Zisi C, Sampsonidis I, Virgiliou C, Theodoridis G, Gika H, Nikitas P, Pappa-Louisi A. Multivariate analysis of chromatographic retention data as a supplementary means for grouping structurally related compounds. J Chromatogr A 2015; 1387:49-52. [DOI: 10.1016/j.chroma.2015.01.083] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 01/27/2015] [Accepted: 01/28/2015] [Indexed: 01/20/2023]
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192
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Daskalaki E, Blackburn G, Kalna G, Zhang T, Anthony N, Watson DG. A study of the effects of exercise on the urinary metabolome using normalisation to individual metabolic output. Metabolites 2015; 5:119-39. [PMID: 25734341 PMCID: PMC4381293 DOI: 10.3390/metabo5010119] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2014] [Revised: 02/13/2015] [Accepted: 02/22/2015] [Indexed: 12/30/2022] Open
Abstract
Aerobic exercise, in spite of its multi-organ benefit and potent effect on the metabolome, has yet to be investigated comprehensively via an untargeted metabolomics technology. We conducted an exploratory untargeted liquid chromatography mass spectrometry study to investigate the effects of a one-h aerobic exercise session in the urine of three physically active males. Individual urine samples were collected over a 37-h protocol (two pre-exercise and eight post-exercise). Raw data were subjected to a variety of normalization techniques, with the most effective measure dividing each metabolite by the sum response of that metabolite for each individual across the 37-h protocol expressed as a percentage. This allowed the metabolite responses to be plotted on a normalised scale. Our results highlight significant metabolites located in the following systems: purine pathway, tryptophan metabolism, carnitine metabolism, cortisol metabolism, androgen metabolism, amino acid oxidation, as well as metabolites from the gastrointestinal microbiome. Many of the significant changes observed in our pilot investigation mirror previous research studies, of various methodological designs, published within the last 15 years, although they have never been reported at the same time in a single study.
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Affiliation(s)
- Evangelia Daskalaki
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow G4 0RE, UK.
| | - Gavin Blackburn
- Glasgow Polyomics, University of Glasgow, Wolfson Wohl Cancer Research Centre, Glasgow G61 1 BD, UK.
| | - Gabriela Kalna
- The Beatson Institute for Cancer Research, Garscube Estate, Glasgow G61 1BD, UK.
| | - Tong Zhang
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow G4 0RE, UK.
| | - Nahoum Anthony
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow G4 0RE, UK.
| | - David G Watson
- Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow G4 0RE, UK.
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193
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Bestatin induces specific changes in Trypanosoma cruzi dipeptide pool. Antimicrob Agents Chemother 2015; 59:2921-5. [PMID: 25712359 DOI: 10.1128/aac.05046-14] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/28/2014] [Accepted: 02/16/2015] [Indexed: 11/20/2022] Open
Abstract
Proteases and peptidases in Trypanosoma cruzi are considered potential targets for antichagasic chemotherapy. We monitored changes in low-mass metabolites in T. cruzi epimastigotes treated with bestatin, a dipeptide metalloaminopeptidase inhibitor. After treatment, multiple dipeptides were shown to be increased, confirming in situ inhibition of the leucine aminopeptidase of T. cruzi (LAPTc) and probably other peptidases.
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194
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Nielsen KF, Larsen TO. The importance of mass spectrometric dereplication in fungal secondary metabolite analysis. Front Microbiol 2015; 6:71. [PMID: 25741325 PMCID: PMC4330896 DOI: 10.3389/fmicb.2015.00071] [Citation(s) in RCA: 49] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2014] [Accepted: 01/20/2015] [Indexed: 11/13/2022] Open
Abstract
Having entered the Genomic Era, it is now evident that the biosynthetic potential of filamentous fungi is much larger than was thought even a decade ago. Fungi harbor many cryptic gene clusters encoding for the biosynthesis of polyketides, non-ribosomal peptides, and terpenoids - which can all undergo extensive modifications by tailoring enzymes - thus potentially providing a large array of products from a single pathway. Elucidating the full chemical profile of a fungal species is a challenging exercise, even with elemental composition provided by high-resolution mass spectrometry (HRMS) used in combination with chemical databases (e.g., AntiBase) to dereplicate known compounds. This has led to a continuous effort to improve chromatographic separation in conjunction with improvement in HRMS detection. Major improvements have also occurred with 2D chromatography, ion-mobility, MS/MS and MS(3), stable isotope labeling feeding experiments, classic UV/Vis, and especially automated data-mining and metabolomics software approaches as the sheer amount of data generated is now the major challenge. This review will focus on the development and implementation of dereplication strategies and will highlight the importance of each stage of the process from sample preparation to chromatographic separation and finally toward both manual and more targeted methods for automated dereplication of fungal natural products using state-of-the art MS instrumentation.
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Affiliation(s)
- Kristian F Nielsen
- Department of Systems Biology, Technical University of Denmark, Kongens Lyngby Denmark
| | - Thomas O Larsen
- Department of Systems Biology, Technical University of Denmark, Kongens Lyngby Denmark
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195
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Nikolskiy I, Siuzdak G, Patti GJ. Discriminating precursors of common fragments for large-scale metabolite profiling by triple quadrupole mass spectrometry. Bioinformatics 2015; 31:2017-23. [PMID: 25691443 DOI: 10.1093/bioinformatics/btv085] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2014] [Accepted: 02/05/2015] [Indexed: 11/14/2022] Open
Abstract
MOTIVATION The goal of large-scale metabolite profiling is to compare the relative concentrations of as many metabolites extracted from biological samples as possible. This is typically accomplished by measuring the abundances of thousands of ions with high-resolution and high mass accuracy mass spectrometers. Although the data from these instruments provide a comprehensive fingerprint of each sample, identifying the structures of the thousands of detected ions is still challenging and time intensive. An alternative, less-comprehensive approach is to use triple quadrupole (QqQ) mass spectrometry to analyze predetermined sets of metabolites (typically fewer than several hundred). This is done using authentic standards to develop QqQ experiments that specifically detect only the targeted metabolites, with the advantage that the need for ion identification after profiling is eliminated. RESULTS Here, we propose a framework to extend the application of QqQ mass spectrometers to large-scale metabolite profiling. We aim to provide a foundation for designing QqQ multiple reaction monitoring (MRM) experiments for each of the 82 696 metabolites in the METLIN metabolite database. First, we identify common fragmentation products from the experimental fragmentation data in METLIN. Then, we model the likelihoods of each precursor structure in METLIN producing each common fragmentation product. With these likelihood estimates, we select ensembles of common fragmentation products that minimize our uncertainty about metabolite identities. We demonstrate encouraging performance and, based on our results, we suggest how our method can be integrated with future work to develop large-scale MRM experiments. AVAILABILITY AND IMPLEMENTATION Our predictions, Supplementary results, and the code for estimating likelihoods and selecting ensembles of fragmentation reactions are made available on the lab website at http://pattilab.wustl.edu/FragPred.
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Affiliation(s)
- Igor Nikolskiy
- Department of Genetics, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA, Scripps Center for Metabolomics and Mass Spectrometry, Departments of Chemistry, Molecular and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA and Department of Chemistry, Washington University, St. Louis, MO 63130, USA
| | - Gary Siuzdak
- Department of Genetics, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA, Scripps Center for Metabolomics and Mass Spectrometry, Departments of Chemistry, Molecular and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA and Department of Chemistry, Washington University, St. Louis, MO 63130, USA
| | - Gary J Patti
- Department of Genetics, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA, Scripps Center for Metabolomics and Mass Spectrometry, Departments of Chemistry, Molecular and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA and Department of Chemistry, Washington University, St. Louis, MO 63130, USA Department of Genetics, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA, Scripps Center for Metabolomics and Mass Spectrometry, Departments of Chemistry, Molecular and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA and Department of Chemistry, Washington University, St. Louis, MO 63130, USA Department of Genetics, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110, USA, Scripps Center for Metabolomics and Mass Spectrometry, Departments of Chemistry, Molecular and Computational Biology, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, California 92037, USA and Department of Chemistry, Washington University, St. Louis, MO 63130, USA
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196
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Wandy J, Daly R, Breitling R, Rogers S. Incorporating peak grouping information for alignment of multiple liquid chromatography-mass spectrometry datasets. Bioinformatics 2015; 31:1999-2006. [PMID: 25649621 PMCID: PMC4760236 DOI: 10.1093/bioinformatics/btv072] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2014] [Accepted: 01/28/2015] [Indexed: 11/24/2022] Open
Abstract
Motivation: The combination of liquid chromatography and mass spectrometry (LC/MS) has been widely used for large-scale comparative studies in systems biology, including proteomics, glycomics and metabolomics. In almost all experimental design, it is necessary to compare chromatograms across biological or technical replicates and across sample groups. Central to this is the peak alignment step, which is one of the most important but challenging preprocessing steps. Existing alignment tools do not take into account the structural dependencies between related peaks that coelute and are derived from the same metabolite or peptide. We propose a direct matching peak alignment method for LC/MS data that incorporates related peaks information (within each LC/MS run) and investigate its effect on alignment performance (across runs). The groupings of related peaks necessary for our method can be obtained from any peak clustering method and are built into a pair-wise peak similarity score function. The similarity score matrix produced is used by an approximation algorithm for the weighted matching problem to produce the actual alignment result. Results: We demonstrate that related peak information can improve alignment performance. The performance is evaluated on a set of benchmark datasets, where our method performs competitively compared to other popular alignment tools. Availability: The proposed alignment method has been implemented as a stand-alone application in Python, available for download at http://github.com/joewandy/peak-grouping-alignment. Contact:Simon.Rogers@glasgow.ac.uk Supplementary information:Supplementary data are available at Bioinformatics online.
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Affiliation(s)
- Joe Wandy
- School of Computing Science, University of Glasgow, Glasgow, UK, School of Computing and Mathematical Sciences, Liverpool John Moores University, Merseyside, UK and Manchester Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM), Manchester Institute of Biotechnology, University of Manchester, Manchester, UK
| | - Rónán Daly
- School of Computing Science, University of Glasgow, Glasgow, UK, School of Computing and Mathematical Sciences, Liverpool John Moores University, Merseyside, UK and Manchester Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM), Manchester Institute of Biotechnology, University of Manchester, Manchester, UK
| | - Rainer Breitling
- School of Computing Science, University of Glasgow, Glasgow, UK, School of Computing and Mathematical Sciences, Liverpool John Moores University, Merseyside, UK and Manchester Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM), Manchester Institute of Biotechnology, University of Manchester, Manchester, UK
| | - Simon Rogers
- School of Computing Science, University of Glasgow, Glasgow, UK, School of Computing and Mathematical Sciences, Liverpool John Moores University, Merseyside, UK and Manchester Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM), Manchester Institute of Biotechnology, University of Manchester, Manchester, UK
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197
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Wolfender JL, Marti G, Thomas A, Bertrand S. Current approaches and challenges for the metabolite profiling of complex natural extracts. J Chromatogr A 2015; 1382:136-64. [DOI: 10.1016/j.chroma.2014.10.091] [Citation(s) in RCA: 352] [Impact Index Per Article: 39.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Revised: 10/23/2014] [Accepted: 10/26/2014] [Indexed: 12/11/2022]
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198
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Lynn KS, Cheng ML, Chen YR, Hsu C, Chen A, Lih TM, Chang HY, Huang CJ, Shiao MS, Pan WH, Sung TY, Hsu WL. Metabolite Identification for Mass Spectrometry-Based Metabolomics Using Multiple Types of Correlated Ion Information. Anal Chem 2015; 87:2143-51. [DOI: 10.1021/ac503325c] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Affiliation(s)
- Ke-Shiuan Lynn
- Institute of Information
Science, Academia Sinica, Taipei, Taiwan
| | - Mei-Ling Cheng
- Department
of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Yet-Ran Chen
- Agricultural Biotechnology
Research Center, Academia Sinica, Taipei, Taiwan
| | - Chin Hsu
- Department
of Exercise Health Science, National Taiwan University of Physical Education and Sport, Taichung, Taiwan
| | - Ann Chen
- Department
of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan
| | - T. Mamie Lih
- Bioinformatics
Program, TIGP, Institute of Information Science, Academia Sinica, Taipei, Taiwan
| | - Hui-Yin Chang
- Bioinformatics
Program, TIGP, Institute of Information Science, Academia Sinica, Taipei, Taiwan
| | - Ching-jang Huang
- Department
of Biochemical Science and Technology, National Taiwan University, Taipei, Taiwan
| | - Ming-Shi Shiao
- Department
of Biomedical Sciences, Chang Gung University, Taoyuan, Taiwan
| | - Wen-Harn Pan
- Institute of Biomedical
Sciences, Academia Sinica, Taipei, Taiwan
| | - Ting-Yi Sung
- Institute of Information
Science, Academia Sinica, Taipei, Taiwan
| | - Wen-Lian Hsu
- Institute of Information
Science, Academia Sinica, Taipei, Taiwan
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199
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Tufi S, Lamoree MH, De Boer J, Leonards PEG. Cross-platform metabolic profiling: application to the aquatic model organism Lymnaea stagnalis. Anal Bioanal Chem 2015; 407:1901-12. [DOI: 10.1007/s00216-014-8431-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2014] [Accepted: 12/18/2014] [Indexed: 12/13/2022]
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200
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Affiliation(s)
- Caroline H. Johnson
- Scripps
Center for Metabolomics and Mass Spectrometry, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Julijana Ivanisevic
- Scripps
Center for Metabolomics and Mass Spectrometry, The Scripps Research Institute, La Jolla, California 92037, United States
| | - H. Paul Benton
- Scripps
Center for Metabolomics and Mass Spectrometry, The Scripps Research Institute, La Jolla, California 92037, United States
| | - Gary Siuzdak
- Scripps
Center for Metabolomics and Mass Spectrometry, The Scripps Research Institute, La Jolla, California 92037, United States
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