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Banahene N, Peters-Clarke TM, Biegas KJ, Shishkova E, Hart EM, McKitterick AC, Kambitsis NH, Johnson UG, Bernhardt TG, Coon JJ, Swarts BM. Chemical Proteomics Strategies for Analyzing Protein Lipidation Reveal the Bacterial O-Mycoloylome. J Am Chem Soc 2024; 146:12138-12154. [PMID: 38635392 PMCID: PMC11066868 DOI: 10.1021/jacs.4c02278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2024] [Revised: 04/04/2024] [Accepted: 04/05/2024] [Indexed: 04/20/2024]
Abstract
Protein lipidation dynamically controls protein localization and function within cellular membranes. A unique form of protein O-fatty acylation in Corynebacterium, termed protein O-mycoloylation, involves the attachment of mycolic acids─unusually large and hydrophobic fatty acids─to serine residues of proteins in these organisms' outer mycomembrane. However, as with other forms of protein lipidation, the scope and functional consequences of protein O-mycoloylation are challenging to investigate due to the inherent difficulties of enriching and analyzing lipidated peptides. To facilitate the analysis of protein lipidation and enable the comprehensive profiling and site mapping of protein O-mycoloylation, we developed a chemical proteomics strategy integrating metabolic labeling, click chemistry, cleavable linkers, and a novel liquid chromatography-tandem mass spectrometry (LC-MS/MS) method employing LC separation and complementary fragmentation methods tailored to the analysis of lipophilic, MS-labile O-acylated peptides. Using these tools in the model organism Corynebacterium glutamicum, we identified approximately 30 candidate O-mycoloylated proteins, including porins, mycoloyltransferases, secreted hydrolases, and other proteins with cell envelope-related functions─consistent with a role for O-mycoloylation in targeting proteins to the mycomembrane. Site mapping revealed that many of the proteins contained multiple spatially proximal modification sites, which occurred predominantly at serine residues surrounded by conformationally flexible peptide motifs. Overall, this study (i) discloses the putative protein O-mycoloylome for the first time, (ii) yields new insights into the undercharacterized proteome of the mycomembrane, which is a hallmark of important pathogens (e.g., Corynebacterium diphtheriae, Mycobacterium tuberculosis), and (iii) provides generally applicable chemical strategies for the proteomic analysis of protein lipidation.
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Affiliation(s)
- Nicholas Banahene
- Department
of Chemistry and Biochemistry, Central Michigan
University, Mount
Pleasant, Michigan 48859, United States
- Biochemistry,
Cell, and Molecular Biology Graduate Programs, Central Michigan University, Mount
Pleasant, Michigan 48859, United States
| | - Trenton M. Peters-Clarke
- Department
of Chemistry, University of Wisconsin, Madison, Wisconsin 53562, United States
- Department
of Biomolecular Chemistry, University of
Wisconsin, Madison, Wisconsin 53562, United States
- National
Center for Quantitative Biology of Complex Systems, University of Wisconsin, Madison, Wisconsin 53562, United States
| | - Kyle J. Biegas
- Department
of Chemistry and Biochemistry, Central Michigan
University, Mount
Pleasant, Michigan 48859, United States
- Biochemistry,
Cell, and Molecular Biology Graduate Programs, Central Michigan University, Mount
Pleasant, Michigan 48859, United States
| | - Evgenia Shishkova
- Department
of Biomolecular Chemistry, University of
Wisconsin, Madison, Wisconsin 53562, United States
- National
Center for Quantitative Biology of Complex Systems, University of Wisconsin, Madison, Wisconsin 53562, United States
| | - Elizabeth M. Hart
- Department
of Microbiology, Harvard Medical School, Boston, Massachusetts 02115 United States
- Howard
Hughes Medical Institute, Chevy
Chase, Maryland 20815, United States
| | - Amelia C. McKitterick
- Department
of Microbiology, Harvard Medical School, Boston, Massachusetts 02115 United States
- Howard
Hughes Medical Institute, Chevy
Chase, Maryland 20815, United States
| | - Nikolas H. Kambitsis
- Department
of Chemistry and Biochemistry, Central Michigan
University, Mount
Pleasant, Michigan 48859, United States
| | - Ulysses G. Johnson
- Department
of Chemistry and Biochemistry, Central Michigan
University, Mount
Pleasant, Michigan 48859, United States
- Biochemistry,
Cell, and Molecular Biology Graduate Programs, Central Michigan University, Mount
Pleasant, Michigan 48859, United States
| | - Thomas G. Bernhardt
- Department
of Microbiology, Harvard Medical School, Boston, Massachusetts 02115 United States
- Howard
Hughes Medical Institute, Chevy
Chase, Maryland 20815, United States
| | - Joshua J. Coon
- Department
of Chemistry, University of Wisconsin, Madison, Wisconsin 53562, United States
- Department
of Biomolecular Chemistry, University of
Wisconsin, Madison, Wisconsin 53562, United States
- National
Center for Quantitative Biology of Complex Systems, University of Wisconsin, Madison, Wisconsin 53562, United States
- Morgridge
Institute for Research, Madison, Wisconsin 53562, United States
| | - Benjamin M. Swarts
- Department
of Chemistry and Biochemistry, Central Michigan
University, Mount
Pleasant, Michigan 48859, United States
- Biochemistry,
Cell, and Molecular Biology Graduate Programs, Central Michigan University, Mount
Pleasant, Michigan 48859, United States
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Barreiro C, Ibáñez AM. Bidimensional Analyses of the Intra- and Extracellular Proteomes of Steroid Producer Mycobacteria. Methods Mol Biol 2023; 2704:115-141. [PMID: 37642841 DOI: 10.1007/978-1-0716-3385-4_7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/31/2023]
Abstract
The importance of the pathogenic mycobacteria has mainly focused the omic analyses on different aspects of their clinical significance. However, those industrially relevant mycobacteria have received less attention, even though the steroid market sales in 2021 were estimated in $56.45 billion.The extracellular proteome, due to its relevance in the sterol processing and uptake, and the intracellular proteome, because of its role in steroids bioconversion, are the core of the present chapter. Both, monodimensional gels, as preparatory analysis, and bidimensional gels as proteome analysis are described. As a proof of concept, the protein extraction methods for both sub-proteomes of Mycobacterium are described. Thus, procedures and relevant key points of these proteome analyses are fully detailed.
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Affiliation(s)
- Carlos Barreiro
- Área de Bioquímica y Biología Molecular, Departamento de Biología Molecular, Facultad de Veterinaria, Universidad de León, León, Spain.
| | - Ana M Ibáñez
- Instituto de Investigación de la Viña y el Vino, Escuela de Ingeniería Agraria, Universidad de León, León, Spain
- Instituto Tecnológico Agrario de Castilla y León (ITACyL), Área de Investigación Agrícola, Valladolid, Spain
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Characterization of the Protective Immune Responses Conferred by Recombinant BCG Overexpressing Components of Mycobacterium tuberculosis Sec Protein Export System. Vaccines (Basel) 2022; 10:vaccines10060945. [PMID: 35746553 PMCID: PMC9229301 DOI: 10.3390/vaccines10060945] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2022] [Revised: 06/08/2022] [Accepted: 06/12/2022] [Indexed: 11/29/2022] Open
Abstract
Mycobacterium bovis Bacillus Calmette-Guérin (BCG) is the only approved vaccine against tuberculosis (TB). However, its efficacy in preventing pulmonary TB in adults is limited. Despite its variable efficacy, BCG offers a number of unique and beneficial characteristics, which make it suitable as a vaccine vehicle to express recombinant molecules. In Mycobacterium tuberculosis, the general Sec pathway is an essential cellular process, and it is responsible for exporting the majority of proteins across the cytoplasmic membrane, including potent immune-protective antigens, such as members of the antigen 85 (Ag85) complex. We engineered BCG to overexpress the M. tuberculosis SecDFG proteins in order to improve the efficiency of the Sec-dependent export system and, thus, enhance the secretion of immunogenic proteins. BCGSecDFG displayed increased intracellular survival within macrophages in vitro and greater persistence in the lymphoid organs of vaccinated mice than parental BCG. In addition, vaccination with BCGSecDFG generated higher numbers of IFN-γ-secreting T cells in response to secreted mycobacterial antigens compared to BCG, particularly members of the Ag85 complex. Furthermore, vaccination with BCGSecDFG significantly reduced the bacterial load in the lungs and spleens of M. tuberculosis-infected mice, which was comparable to the protection afforded by parental BCG. Therefore, the modification of protein secretion in BCG can improve antigen-specific immunogenicity.
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4
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Lee H, Kim SI. Review of Liquid Chromatography-Mass Spectrometry-Based Proteomic Analyses of Body Fluids to Diagnose Infectious Diseases. Int J Mol Sci 2022; 23:ijms23042187. [PMID: 35216306 PMCID: PMC8878692 DOI: 10.3390/ijms23042187] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2021] [Revised: 02/11/2022] [Accepted: 02/14/2022] [Indexed: 01/27/2023] Open
Abstract
Rapid and precise diagnostic methods are required to control emerging infectious diseases effectively. Human body fluids are attractive clinical samples for discovering diagnostic targets because they reflect the clinical statuses of patients and most of them can be obtained with minimally invasive sampling processes. Body fluids are good reservoirs for infectious parasites, bacteria, and viruses. Therefore, recent clinical proteomics methods have focused on body fluids when aiming to discover human- or pathogen-originated diagnostic markers. Cutting-edge liquid chromatography-mass spectrometry (LC-MS)-based proteomics has been applied in this regard; it is considered one of the most sensitive and specific proteomics approaches. Here, the clinical characteristics of each body fluid, recent tandem mass spectroscopy (MS/MS) data-acquisition methods, and applications of body fluids for proteomics regarding infectious diseases (including the coronavirus disease of 2019 [COVID-19]), are summarized and discussed.
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Affiliation(s)
- Hayoung Lee
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute (KBSI), Ochang 28119, Korea;
- Bio-Analytical Science Division, University of Science and Technology (UST), Daejeon 34113, Korea
| | - Seung Il Kim
- Research Center for Bioconvergence Analysis, Korea Basic Science Institute (KBSI), Ochang 28119, Korea;
- Bio-Analytical Science Division, University of Science and Technology (UST), Daejeon 34113, Korea
- Correspondence:
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5
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Assal N, Rennie B, Walrond L, Cyr T, Rohonczy L, Lin M. Proteome characterization of the culture supernatant of Mycobacterium bovis in different growth stages. Biochem Biophys Rep 2021; 28:101154. [PMID: 34746449 PMCID: PMC8554454 DOI: 10.1016/j.bbrep.2021.101154] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2021] [Revised: 10/11/2021] [Accepted: 10/13/2021] [Indexed: 11/16/2022] Open
Abstract
This study aimed to identify proteins secreted by Mycobacterium bovis into culture medium at different stages of bacterial growth. A field strain of M. bovis was grown in Middlebrook 7H9 media and culture supernatant was collected at three-time points representing three different phases of growth (early exponential, late exponential, and stationary phases). Supernatants were double filtered, digested by trypsin and analyzed by LC-MS/MS. The study found 15, 21, and 16 proteins in early, mid and late growth phases, respectively. In total, 22 proteins were identified, 18 of which were reported or predicted to have a cell wall or extracellular localization. To our knowledge, this is the first study to identify proteins secreted into the culture medium by a field strain of M. bovis in three different stages of growth. The dataset generated here provides candidate proteins with the potential for the development of serological diagnostic reagents or vaccine for bovine tuberculosis. Data are available via ProteomeXchange with identifier PXD017817. Identifying extracellular proteins produced by M. bovis using mass spectrometry. Culture supernatant proteins secreted in three different stages of bacterial growth. Proteins were secreted from live bacteria and heat-killing was omitted.
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Affiliation(s)
- Nadia Assal
- Ottawa Laboratory Fallowfield, Canadian Food Inspection Agency, Ottawa, ON, Canada.,Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
| | - Bryan Rennie
- Ottawa Laboratory Fallowfield, Canadian Food Inspection Agency, Ottawa, ON, Canada
| | - Lisa Walrond
- Centre for Vaccine Evaluation, Health Canada, Ottawa, ON, Canada
| | - Terry Cyr
- Centre for Vaccine Evaluation, Health Canada, Ottawa, ON, Canada
| | - Liz Rohonczy
- Ottawa Laboratory Fallowfield, Canadian Food Inspection Agency, Ottawa, ON, Canada
| | - Min Lin
- Ottawa Laboratory Fallowfield, Canadian Food Inspection Agency, Ottawa, ON, Canada.,Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, ON, Canada
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6
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Kumar S, Bhaskar A, Patnaik G, Sharma C, Singh DK, Kaushik SR, Chaturvedi S, Das G, Dwivedi VP. Intranasal immunization with peptide-based immunogenic complex enhances BCG vaccine efficacy in a murine model of tuberculosis. JCI Insight 2021; 6:145228. [PMID: 33444288 PMCID: PMC7934935 DOI: 10.1172/jci.insight.145228] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 01/07/2021] [Indexed: 12/23/2022] Open
Abstract
Prime-boost immunization strategies are required to control the global tuberculosis (TB) pandemic, which claims approximately 3 lives every minute. Here, we have generated an immunogenic complex against Mycobacterium tuberculosis (M.tb), consisting of promiscuous T cell epitopes (M.tb peptides) and TLR ligands assembled in liposomes. Interestingly, this complex (peptide–TLR agonist–liposomes; PTL) induced significant activation of CD4+ T cells and IFN-γ production in the PBMCs derived from PPD+ healthy individuals as compared with PPD– controls. Furthermore, intranasal delivery of PTL significantly reduced the bacterial burden in the infected mice by inducing M.tb-specific polyfunctional (IFN-γ+IL-17+TNF-α+IL-2+) immune responses and long-lasting central memory responses, thereby reducing the risk of TB recurrence in DOTS-treated infected animals. The transcriptome analysis of peptide-stimulated immune cells unveiled the molecular basis of enhanced protection. Furthermore, PTL immunization significantly boosted the Bacillus Calmette-Guerin–primed (BCG-primed) immune responses against TB. The greatly enhanced efficacy of the BCG-PTL vaccine model in controlling pulmonary TB projects PTL as an adjunct vaccine against TB.
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Affiliation(s)
- Santosh Kumar
- International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Ashima Bhaskar
- Signal Transduction Laboratory-1, National Institute of Immunology, New Delhi, India
| | - Gautam Patnaik
- Special Center for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Chetan Sharma
- International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Dhiraj Kumar Singh
- Special Center for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Sandeep Rai Kaushik
- International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Shivam Chaturvedi
- International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
| | - Gobardhan Das
- Special Center for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India
| | - Ved Prakash Dwivedi
- International Centre for Genetic Engineering and Biotechnology (ICGEB), New Delhi, India
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7
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Larsen MH, Lacourciere K, Parker TM, Kraigsley A, Achkar JM, Adams LB, Dupnik KM, Hall-Stoodley L, Hartman T, Kanipe C, Kurtz SL, Miller MA, Salvador LCM, Spencer JS, Robinson RT. The Many Hosts of Mycobacteria 8 (MHM8): A conference report. Tuberculosis (Edinb) 2020; 121:101914. [PMID: 32279870 PMCID: PMC7428850 DOI: 10.1016/j.tube.2020.101914] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2019] [Revised: 02/07/2020] [Accepted: 02/09/2020] [Indexed: 12/18/2022]
Abstract
Mycobacteria are important causes of disease in human and animal hosts. Diseases caused by mycobacteria include leprosy, tuberculosis (TB), nontuberculous mycobacteria (NTM) infections and Buruli Ulcer. To better understand and treat mycobacterial disease, clinicians, veterinarians and scientists use a range of discipline-specific approaches to conduct basic and applied research, including conducting epidemiological surveys, patient studies, wildlife sampling, animal models, genetic studies and computational simulations. To foster the exchange of knowledge and collaboration across disciplines, the Many Hosts of Mycobacteria (MHM) conference series brings together clinical, veterinary and basic scientists who are dedicated to advancing mycobacterial disease research. Started in 2007, the MHM series recently held its 8th conference at the Albert Einstein College of Medicine (Bronx, NY). Here, we review the diseases discussed at MHM8 and summarize the presentations on research advances in leprosy, NTM and Buruli Ulcer, human and animal TB, mycobacterial disease comorbidities, mycobacterial genetics and 'omics, and animal models. A mouse models workshop, which was held immediately after MHM8, is also summarized. In addition to being a resource for those who were unable to attend MHM8, we anticipate this review will provide a benchmark to gauge the progress of future research concerning mycobacteria and their many hosts.
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Affiliation(s)
- Michelle H Larsen
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Karen Lacourciere
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20892, USA
| | - Tina M Parker
- National Institute of Allergy and Infectious Diseases, National Institutes of Health, Rockville, MD 20892, USA
| | - Alison Kraigsley
- Center for Infectious Disease Research and Policy, University of Minnesota, Minneapolis, MN, USA
| | - Jacqueline M Achkar
- Department of Microbiology and Immunology, Albert Einstein College of Medicine, Bronx, NY, USA; Department of Medicine, Albert Einstein College of Medicine, Bronx, NY, USA
| | - Linda B Adams
- Department of Health and Human Services, Health Resources and Services Administration, Healthcare Systems Bureau, National Hansen's Disease Programs, Baton Rouge, LA, USA
| | - Kathryn M Dupnik
- Center for Global Health, Department of Medicine, Weill Cornell Medicine, New York, NY, USA
| | - Luanne Hall-Stoodley
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA
| | - Travis Hartman
- Center for Global Health, Department of Medicine, Weill Cornell Medicine, New York, NY, USA
| | - Carly Kanipe
- Department of Immunobiology, Iowa State University, Ames, IA, USA; Oak Ridge Institute for Science and Education, Oak Ridge, TN, USA; Bacterial Diseases of Livestock Research Unit, National Animal Disease Center, Agricultural Research Service, United States Department of Agriculture, Ames, IA, USA
| | - Sherry L Kurtz
- Laboratory of Mucosal Pathogens and Cellular Immunology, Division of Bacterial, Parasitic and Allergenic Products, Center for Biologics Evaluation and Research, Food and Drug Administration, Washington, DC, USA
| | - Michele A Miller
- DST-NRF Centre of Excellence for Biomedical Tuberculosis Research, South African Medical Research Council Centre for Tuberculosis Research, Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town, South Africa
| | - Liliana C M Salvador
- Department of Infectious Diseases, University of Georgia, Athens, GA, USA; Institute of Bioinformatics, University of Georgia, Athens, GA, USA; Center for the Ecology of Infectious Diseases, University of Georgia, Athens, GA, USA
| | - John S Spencer
- Department of Microbiology, Immunology, and Pathology, Mycobacteria Research Laboratories, Colorado State University, Fort Collins, CO, USA
| | - Richard T Robinson
- Department of Microbial Infection and Immunity, The Ohio State University, Columbus, OH, USA.
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Saleh S, Staes A, Deborggraeve S, Gevaert K. Targeted Proteomics for Studying Pathogenic Bacteria. Proteomics 2019; 19:e1800435. [DOI: 10.1002/pmic.201800435] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2019] [Revised: 06/04/2019] [Indexed: 02/04/2023]
Affiliation(s)
- Sara Saleh
- Department of Biomedical SciencesInstitute of Tropical Medicine B‐2000 Antwerp Belgium
- VIB Center for Medical Biotechnology B‐9000 Ghent Belgium
- Department of Biomolecular MedicineGhent University B‐9000 Ghent Belgium
| | - An Staes
- VIB Center for Medical Biotechnology B‐9000 Ghent Belgium
- Department of Biomolecular MedicineGhent University B‐9000 Ghent Belgium
| | - Stijn Deborggraeve
- Department of Biomedical SciencesInstitute of Tropical Medicine B‐2000 Antwerp Belgium
| | - Kris Gevaert
- VIB Center for Medical Biotechnology B‐9000 Ghent Belgium
- Department of Biomolecular MedicineGhent University B‐9000 Ghent Belgium
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9
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Haghighi F, Talebpour Z, Nezhad AS. Towards fully integrated liquid chromatography on a chip: Evolution and evaluation. Trends Analyt Chem 2018. [DOI: 10.1016/j.trac.2018.05.002] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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10
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Gilar M, McDonald TS, Gritti F, Roman GT, Johnson JS, Bunner B, Michienzi JD, Collamati RA, Murphy JP, Satpute DD, Bannon MP, DellaRovere D, Jencks RA, Dourdeville TA, Fadgen KE, Gerhardt GC. Chromatographic performance of microfluidic liquid chromatography devices: Experimental evaluation of straight versus serpentine packed channels. J Chromatogr A 2017; 1533:127-135. [PMID: 29249537 DOI: 10.1016/j.chroma.2017.12.031] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2017] [Revised: 12/06/2017] [Accepted: 12/12/2017] [Indexed: 10/18/2022]
Abstract
We prepared a series of planar titanium microfluidic (μLC) columns, each 100 mm long, with 0.15, 0.3 and 0.5 mm i.d.'s. The microfluidic columns were packed with 1.8 μm C18 sorbent and tested under isocratic and gradient conditions. The efficiency and peak capacity of these devices were monitored using a micro LC instrument with minimal extra column dispersion. Columns with serpentine channels were shown to perform worse than those with straight channels. The loss of efficiency and peak capacity was more prominent for wider i.d. columns, presumably due to on-column band broadening imparted by the so-called "race-track" effect. The loss of chromatographic performance was partially mitigated by tapering the turns (reduction in i.d. through the curved region). While good performance was obtained for 0.15 mm i.d. devices even without turn tapering, the performance of 0.3 mm i.d. columns could be brought on par with capillary LC devices by tapering down to 2/3 of the nominal channel width in the turn regions. The loss of performance was not fully compensated for in 0.5 mm devices even when tapering was employed; 30% loss in efficiency and 10% loss in peak capacity was observed. The experimental data for various devices were compared using the expected theoretical relationship between peak capacity Pc and efficiency N; (Pc-1) = N0.5 × const. While straight μLC columns showed the expected behavior, the devices with serpentine channels did not adhere to the plot. The results suggest that the loss of efficiency due to the turns is more pronounced than the corresponding loss of peak capacity.
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Affiliation(s)
- Martin Gilar
- Waters Corporation, 34 Maple Street, Milford, MA 01757, USA.
| | | | - Fabrice Gritti
- Waters Corporation, 34 Maple Street, Milford, MA 01757, USA
| | | | - Jay S Johnson
- Waters Corporation, 34 Maple Street, Milford, MA 01757, USA
| | - Bernard Bunner
- Waters Corporation, 34 Maple Street, Milford, MA 01757, USA
| | | | | | - Jim P Murphy
- Waters Corporation, 34 Maple Street, Milford, MA 01757, USA
| | | | | | | | | | | | - Keith E Fadgen
- Waters Corporation, 34 Maple Street, Milford, MA 01757, USA
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11
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Potential of High-Affinity, Slow Off-Rate Modified Aptamer Reagents for Mycobacterium tuberculosis Proteins as Tools for Infection Models and Diagnostic Applications. J Clin Microbiol 2017; 55:3072-3088. [PMID: 28794178 PMCID: PMC5625393 DOI: 10.1128/jcm.00469-17] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2017] [Accepted: 07/11/2017] [Indexed: 01/12/2023] Open
Abstract
Direct pathogen detection in blood to diagnose active tuberculosis (TB) has been difficult due to low levels of circulating antigens or due to the lack of specific, high-affinity binding reagents and reliable assays with adequate sensitivity. We sought to determine whether slow off-rate modified aptamer (SOMAmer) reagents with subnanomolar affinity for Mycobacterium tuberculosis proteins (antigens 85A, 85B, 85C, GroES, GroEL2, DnaK, CFP10, KAD, CFP2, RplL, and Tpx) could be useful to diagnose tuberculosis. When incorporated into the multiplexed, array-based proteomic SOMAscan assay, limits of detection reached the subpicomolar range in 40% serum. Binding to native M. tuberculosis proteins was confirmed by using M. tuberculosis culture filtrate proteins and fractions from infected macrophages and via affinity capture assays and subsequent mass spectrometry. Comparison of serum from culture-positive pulmonary TB patients and TB suspects systematically ruled out for TB revealed small but statistically significant (P < 0.0001) differences in the median M. tuberculosis signals and in specific pathogen markers, such as antigen 85B. Samples where many M. tuberculosis aptamers produced high signals were rare exceptions. In concentrated, protein-normalized urine from TB patients and non-TB controls, the CFP10 (EsxB) SOMAmer yielded the most significant differential signals (P < 0.0276), particularly in TB patients with HIV coinfection. In conclusion, direct M. tuberculosis antigen detection proved difficult even with a sensitive method such as SOMAscan, likely due to their very low, subpicomolar abundance. The observed differences between cases and controls had limited diagnostic utility in serum and urine, but further evaluation of M. tuberculosis SOMAmers using other platforms and sample types is warranted.
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12
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Mehaffy C, Dobos KM, Nahid P, Kruh-Garcia NA. Second generation multiple reaction monitoring assays for enhanced detection of ultra-low abundance Mycobacterium tuberculosis peptides in human serum. Clin Proteomics 2017; 14:21. [PMID: 28592925 PMCID: PMC5460347 DOI: 10.1186/s12014-017-9156-y] [Citation(s) in RCA: 41] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2017] [Accepted: 05/24/2017] [Indexed: 12/11/2022] Open
Abstract
Background Mycobacterium tuberculosis (Mtb) is the causative agent of Tuberculosis (TB), the number one cause of death due to an infectious disease. TB diagnosis is performed by microscopy, culture or PCR amplification of bacterial DNA, all of which require patient sputum or the biopsy of infected tissue. Detection of mycobacterial products in serum, as biomarkers of diagnosis or disease status would provide an improvement over current methods. Due to the low-abundance of mycobacterial products in serum, we have explored exosome enrichment to improve sensitivity. Mtb resides intracellularly where its secreted proteins have been shown to be packaged into host exosomes and released into the bloodstream. Exosomes can be readily purified assuring an enrichment of mycobacterial analytes from the complex mix of host serum proteins. Methods Multiple reaction monitoring assays were optimized for the enhanced detection of 41 Mtb peptides in exosomes purified from the serum of individuals with TB. Exosomes isolated from the serum of healthy individuals was used to create and validate a unique data analysis algorithm and identify filters to reduce the rate of false positives, attributed to host m/z interference. The final optimized method was tested in 40 exosome samples from TB positive patients. Results Our enhanced methods provide limit of detection and quantification averaging in the low femtomolar range for detection of mycobacterial products in serum. At least one mycobacterial peptide was identified in 92.5% of the TB positive patients. Four peptides from the Mtb proteins, Cfp2, Mpt32, Mpt64 and BfrB, show normalized total peak areas significantly higher in individuals with active TB as compared to healthy controls; three of the peptides from these proteins have not previously been associated with serum exosomes from individuals with active TB disease. Some of the detected peptides were significantly associated with specific geographical locations, highlighting potential markers that can be linked to the Mtb strains circulating within each given region. Conclusions An enhanced MRM method to detect ultra-low abundance Mtb peptides in human serum exosomes is demonstrated, highlighting the potential of this methodology for TB diagnostic biomarker development. Electronic supplementary material The online version of this article (doi:10.1186/s12014-017-9156-y) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Carolina Mehaffy
- Department of Microbiology, Immunology and Pathology, Colorado State University, 1682 Campus Delivery, Fort Collins, CO 80524 USA.,Proteomics and Metabolomics Facility, Colorado State University, 2021 Campus Delivery, Fort Collins, CO 80523 USA
| | - Karen M Dobos
- Department of Microbiology, Immunology and Pathology, Colorado State University, 1682 Campus Delivery, Fort Collins, CO 80524 USA
| | - Payam Nahid
- Division of Pulmonary and Critical Care Medicine, University of California, San Francisco, San Francisco, CA 94143 USA
| | - Nicole A Kruh-Garcia
- Department of Microbiology, Immunology and Pathology, Colorado State University, 1682 Campus Delivery, Fort Collins, CO 80524 USA
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13
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Magombedze G, Shiri T, Eda S, Stabel JR. Inferring biomarkers for Mycobacterium avium subsp. paratuberculosis infection and disease progression in cattle using experimental data. Sci Rep 2017; 7:44765. [PMID: 28317944 PMCID: PMC5357903 DOI: 10.1038/srep44765] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 02/09/2017] [Indexed: 12/31/2022] Open
Abstract
Available diagnostic assays for Mycobacterium avium subsp. paratuberculosis (MAP) have poor sensitivities and cannot detect early stages of infection, therefore, there is need to find new diagnostic markers for early infection detection and disease stages. We analyzed longitudinal IFN-γ, ELISA-antibody and fecal shedding experimental sensitivity scores for MAP infection detection and disease progression. We used both statistical methods and dynamic mathematical models to (i) evaluate the empirical assays (ii) infer and explain biological mechanisms that affect the time evolution of the biomarkers, and (iii) predict disease stages of 57 animals that were naturally infected with MAP. This analysis confirms that the fecal test is the best marker for disease progression and illustrates that Th1/Th2 (IFN-γ/ELISA antibodies) assays are important for infection detection, but cannot reliably predict persistent infections. Our results show that the theoretical simulated macrophage-based assay is a potential good diagnostic marker for MAP persistent infections and predictor of disease specific stages. We therefore recommend specifically designed experiments to test the use of a based assay in the diagnosis of MAP infections.
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Affiliation(s)
- Gesham Magombedze
- Center for Infectious Diseases Research and Experimental Therapeutics, Baylor Research Institute, Baylor University Medical Center, Dallas, TX, USA.,Department of Infectious Disease Epidemiology. Imperial College London, UK.,National Institute for Mathematical and Biological Synthesis, University of Tennessee, Volunteer Blvd, Suite 106, Knoxville, TN, 37996, USA
| | - Tinevimbo Shiri
- Warwick Clinical Trials Unit, Warwick Medical School, University of Warwick, Coventry, UK
| | - Shigetoshi Eda
- National Institute for Mathematical and Biological Synthesis, University of Tennessee, Volunteer Blvd, Suite 106, Knoxville, TN, 37996, USA.,Department of Forestry, Wildlife, and Fisheries, University of Tennessee, Knoxville, TN 37996-1527, USA
| | - Judy R Stabel
- USDA-ARS, National Animal Disease, Ames, IA 50010, USA
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14
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Barreiro C, Morales A, Vázquez-Iglesias I, Sola-Landa A. Intra- and Extra-cellular Proteome Analyses of Steroid-Producer Mycobacteria. Methods Mol Biol 2017; 1645:73-92. [PMID: 28710622 DOI: 10.1007/978-1-4939-7183-1_6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
The importance of the pathogenic mycobacteria has mainly focused the omic analyses on different aspects of their clinical significance. In contrast, those industrially relevant mycobacteria have received less attention, even though the steroids market sales in 2011, in example, were estimated in $8 billion.The extra-cellular proteome, due to its relevance in the sterols processing and uptake; as well as the intra-cellular proteome, because of its role in steroids bioconversion, are the core of the present chapter. As a proof of concept, the obtaining methods for both sub-proteomes of Mycobacterium neoaurum NRRL B-3805, a relevant industrial strain involved in steroids production, have been developed. Thus, procedures and relevant key points of these proteomes analyses are fully described.
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Affiliation(s)
- Carlos Barreiro
- Instituto de Biotecnología de León (INBIOTEC), Parque Científico de León, Avda. Real 1, 24006, León, Spain.
- Área de Microbiología, Departamento de Biología Molecular, Campus de Ponferrada, Universidad de León, Avda. Astorga, s/n, 24400, Ponferrada, Spain.
| | - Alejandro Morales
- Instituto de Biotecnología de León (INBIOTEC), Parque Científico de León, Avda. Real 1, 24006, León, Spain
| | - Inés Vázquez-Iglesias
- Instituto de Biotecnología de León (INBIOTEC), Parque Científico de León, Avda. Real 1, 24006, León, Spain
| | - Alberto Sola-Landa
- Instituto de Biotecnología de León (INBIOTEC), Parque Científico de León, Avda. Real 1, 24006, León, Spain
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15
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Nieto R LM, Mehaffy C, Creissen E, Troudt J, Troy A, Bielefeldt-Ohmann H, Burgos M, Izzo A, Dobos KM. Virulence of Mycobacterium tuberculosis after Acquisition of Isoniazid Resistance: Individual Nature of katG Mutants and the Possible Role of AhpC. PLoS One 2016; 11:e0166807. [PMID: 27893795 PMCID: PMC5125630 DOI: 10.1371/journal.pone.0166807] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2016] [Accepted: 11/03/2016] [Indexed: 11/28/2022] Open
Abstract
In the last decade, there were 10 million new tuberculosis cases per year globally. Around 9.5% of these cases were caused by isoniazid resistant (INHr) Mycobacterium tuberculosis (Mtb) strains. Although isoniazid resistance in Mtb is multigenic, mutations in the catalase-peroxidase (katG) gene predominate among the INHr strains. The effect of these drug-resistance-conferring mutations on Mtb fitness and virulence is variable. Here, we assessed differences in bacterial growth, immune response and pathology induced by Mtb strains harboring mutations at the N-terminus of the katG gene. We studied one laboratory and one clinically isolated Mtb clonal pair from different genetic lineages. The INHr strain in each pair had one and two katG mutations with significantly reduced levels of the enzyme and peroxidase activity. Both strains share the V1A mutation, while the double mutant clinical INHr had also the novel E3V katG mutation. Four groups of C57BL/6 mice were infected with one of the Mtb strains previously described. We observed a strong reduction in virulence (reduced bacterial growth), lower induction of proinflammatory cytokines and significantly reduced pathology scores in mice infected with the clinical INHr strain compared to the infection caused by its INHs progenitor strain. On the other hand, there was a subtle reduction of bacteria growth without differences in the pathology scores in mice infected with the laboratory INHr strain. Our results also showed distinct alkyl-hydroperoxidase C (AhpC) levels in the katG mutant strains, which could explain the difference in the virulence profile observed. The difference in the AhpC levels between clonal strains was not related to a genetic defect in the gene or its promoter. Cumulatively, our results indicate that the virulence, pathology and fitness of INHr strains could be negatively affected by multiple mutations in katG, lack of the peroxidase activity and reduced AhpC levels.
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Affiliation(s)
- Luisa Maria Nieto R
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Carolina Mehaffy
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Elizabeth Creissen
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - JoLynn Troudt
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Amber Troy
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Helle Bielefeldt-Ohmann
- School of Veterinary Science, University of Queensland, Gatton, Queensland, Australia; Australian Infectious Diseases Research Centre, University of Queensland, St Lucia, Queensland, Australia
- School of Chemistry and Molecular Biosciences, University of Queensland, St Lucia, Queensland, Australia
| | - Marcos Burgos
- Division of Infectious Diseases, Department of Medicine, University of New Mexico, Albuquerque, New Mexico, United States of America
| | - Angelo Izzo
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
| | - Karen M. Dobos
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, Colorado, United States of America
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16
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Gilar M, McDonald TS, Gritti F. Experimental evaluation of chromatographic performance of capillary and microfluidic columns with linear or curved channels. J Chromatogr A 2016; 1470:76-83. [DOI: 10.1016/j.chroma.2016.10.004] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Revised: 09/29/2016] [Accepted: 10/05/2016] [Indexed: 11/16/2022]
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17
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Dautin N, de Sousa-d'Auria C, Constantinesco-Becker F, Labarre C, Oberto J, Li de la Sierra-Gallay I, Dietrich C, Issa H, Houssin C, Bayan N. Mycoloyltransferases: A large and major family of enzymes shaping the cell envelope of Corynebacteriales. Biochim Biophys Acta Gen Subj 2016; 1861:3581-3592. [PMID: 27345499 DOI: 10.1016/j.bbagen.2016.06.020] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2016] [Revised: 06/15/2016] [Accepted: 06/16/2016] [Indexed: 12/31/2022]
Abstract
Mycobacterium and Corynebacterium are important genera of the Corynebacteriales order, the members of which are characterized by an atypical diderm cell envelope. Indeed the cytoplasmic membrane of these bacteria is surrounded by a thick mycolic acid-arabinogalactan-peptidoglycan (mAGP) covalent polymer. The mycolic acid-containing part of this complex associates with other lipids (mainly trehalose monomycolate (TMM) and trehalose dimycolate (TDM)) to form an outer membrane. The metabolism of mycolates in the cell envelope is governed by esterases called mycoloyltransferases that catalyze the transfer of mycoloyl chains from TMM to another TMM molecule or to other acceptors such as the terminal arabinoses of arabinogalactan or specific polypeptides. In this review we present an overview of this family of Corynebacteriales enzymes, starting with their expression, localization, structure and activity to finally discuss their putative functions in the cell. In addition, we show that Corynebacteriales possess multiple mycoloyltransferases encoding genes in their genome. The reason for this multiplicity is not known, as their function in mycolates biogenesis appear to be only partially redundant. It is thus possible that, in some species living in specific environments, some mycoloyltransferases have evolved to gain some new functions. In any case, the few characterized mycoloyltransferases are very important for the bacterial physiology and are also involved in adaptation in the host where they constitute major secreted antigens. Although not discussed in this review, all these functions make them interesting targets for the discovery of new antibiotics and promising vaccines candidates. This article is part of a Special Issue entitled "Science for Life" Guest Editor: Dr. Austen Angell, Dr. Salvatore Magazù and Dr. Federica Migliardo.
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Affiliation(s)
- Nathalie Dautin
- Molecular Biology of Corynebacteria and Mycobacteria, Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France
| | - Célia de Sousa-d'Auria
- Molecular Biology of Corynebacteria and Mycobacteria, Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France
| | - Florence Constantinesco-Becker
- Molecular Biology of Corynebacteria and Mycobacteria, Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France
| | - Cécile Labarre
- Molecular Biology of Corynebacteria and Mycobacteria, Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France
| | - Jacques Oberto
- Cell Biology of Archaea, Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France
| | - Ines Li de la Sierra-Gallay
- Function and Architecture of Macromolecular Assemblies, Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France
| | - Christiane Dietrich
- Molecular Biology of Corynebacteria and Mycobacteria, Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France
| | - Hanane Issa
- Molecular Biology of Corynebacteria and Mycobacteria, Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France; Faculty of Sciences, Department of Life and Earth Sciences, Holy Spirit University of Kaslik (USEK), Kaslik, B.P. 446, Jounieh, Lebanon
| | - Christine Houssin
- Molecular Biology of Corynebacteria and Mycobacteria, Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France.
| | - Nicolas Bayan
- Molecular Biology of Corynebacteria and Mycobacteria, Institute for Integrative Biology of the Cell (I2BC), CEA, CNRS, Univ. Paris-Sud, Université Paris-Saclay, 91198 Gif-sur-Yvette Cedex, France.
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18
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Wide injection zone compression in gradient reversed-phase liquid chromatography. J Chromatogr A 2015; 1390:86-94. [PMID: 25748538 DOI: 10.1016/j.chroma.2015.02.057] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2014] [Revised: 02/14/2015] [Accepted: 02/18/2015] [Indexed: 11/21/2022]
Abstract
Chromatographic zone broadening is a common issue in microfluidic chromatography, where the sample volume introduced on column often exceeds the column void volume. To better understand the propagation of wide chromatographic zones on a separation device, a series of MS Excel spreadsheets were developed to simulate the process. To computationally simplify these simulations, we investigated the effects of injection related zone broadening and its gradient related zone compression by tracking only the movements of zone boundaries on column. The effects of sample volume, sample solvent, gradient slope, and column length on zone broadening were evaluated and compared to experiments performed on 0.32mm I.D. microfluidic columns. The repetitive injection method (RIM) was implemented to generate experimental chromatograms where large sample volume scenarios can be emulated by injecting two discrete small injection plugs spaced in time. A good match between predicted and experimental RIM chromatograms was observed. We discuss the performance of selected retention models on the accuracy of predictions and use the developed spreadsheets for illustration of gradient zone focusing for both small molecules and peptides.
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19
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Gilar M, McDonald TS, Roman G, Johnson JS, Murphy JP, Jorgenson JW. Repetitive injection method: a tool for investigation of injection zone formation and its compression in microfluidic liquid chromatography. J Chromatogr A 2015; 1381:110-7. [PMID: 25604268 DOI: 10.1016/j.chroma.2015.01.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2014] [Revised: 12/24/2014] [Accepted: 01/01/2015] [Indexed: 11/18/2022]
Abstract
Sample introduction in microfluidic liquid chromatography often generates wide zones rather than peaks, especially when a large sample volume (relative to column volume) is injected. Formation of wide injection zones can be further amplified when the sample is dissolved in a strong eluent. In some cases sample breakthrough may occur, especially when the injection is performed into short trapping columns. To investigate the band formation and subsequent zone focusing under gradient elution in situations such as these, we developed the Repetitive Injection Method (RIM), based on the temporally resolved introduction of two discrete peaks to a column, mimicking both the leading and trailing edges of a larger, singly injected sample zone. Using titanium microfluidic 0.32 mm I.D. columns, the results of RIM experiments were practically identical to injection of a correspondingly larger single zone volume. It was also experimentally shown that zone width (spacing between two injected peaks) decreases during gradient elution. We utilized RIM experiments to investigate wide sample zones created by strong sample solvent, and subsequent gradient zone focusing for a series of compounds. This experimental work was compared with computationally simulated chromatograms. The success of sample focusing during injection and gradient elution depends not only on an analyte's absolute retention, but also on how rapidly the analyte's retention changes during the mobile phase gradient.
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Affiliation(s)
- Martin Gilar
- Waters Corporation, 34 Maple Street, Milford, MA 01757, USA.
| | | | - Gregory Roman
- Waters Corporation, 34 Maple Street, Milford, MA 01757, USA
| | - Jay S Johnson
- Waters Corporation, 34 Maple Street, Milford, MA 01757, USA
| | - James P Murphy
- Waters Corporation, 34 Maple Street, Milford, MA 01757, USA
| | - James W Jorgenson
- Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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20
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Detection of Mycobacterium tuberculosis peptides in the exosomes of patients with active and latent M. tuberculosis infection using MRM-MS. PLoS One 2014; 9:e103811. [PMID: 25080351 PMCID: PMC4117584 DOI: 10.1371/journal.pone.0103811] [Citation(s) in RCA: 114] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 07/03/2014] [Indexed: 12/13/2022] Open
Abstract
The identification of easily measured, accurate diagnostic biomarkers for active tuberculosis (TB) will have a significant impact on global TB control efforts. Because of the host and pathogen complexities involved in TB pathogenesis, identifying a single biomarker that is adequately sensitive and specific continues to be a major hurdle. Our previous studies in models of TB demonstrated that exosomes, such as those released from infected macrophages, contain mycobacterial products, including many Mtb proteins. In this report, we describe the development of targeted proteomics assays employing multiplexed multiple reaction monitoring mass spectrometry (MRM-MS) in order to allow us to follow those proteins previously identified by western blot or shotgun mass spectrometry, and enhance biomarker discovery to include detection of Mtb proteins in human serum exosomes. Targeted MRM-MS assays were applied to exosomes isolated from human serum samples obtained from culture-confirmed active TB patients to detect 76 peptides representing 33 unique Mtb proteins. Our studies revealed the first identification of bacteria-derived biomarker candidates of active TB in exosomes from human serum. Twenty of the 33 proteins targeted for detection were found in the exosomes of TB patients, and included multiple peptides from 8 proteins (Antigen 85B, Antigen 85C, Apa, BfrB, GlcB, HspX, KatG, and Mpt64). Interestingly, all of these proteins are known mycobacterial adhesins and/or proteins that contribute to the intracellular survival of Mtb. These proteins will be included as target analytes in future validation studies as they may serve as markers for persistent active and latent Mtb infection. In summary, this work is the first step in identifying a unique and specific panel of Mtb peptide biomarkers encapsulated in exosomes and reveals complex biomarker patterns across a spectrum of TB disease states.
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