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Parmar D, Rosado-Rosa JM, Shrout JD, Sweedler JV. Metabolic insights from mass spectrometry imaging of biofilms: A perspective from model microorganisms. Methods 2024; 224:21-34. [PMID: 38295894 PMCID: PMC11149699 DOI: 10.1016/j.ymeth.2024.01.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Revised: 12/17/2023] [Accepted: 01/16/2024] [Indexed: 02/05/2024] Open
Abstract
Biofilms are dense aggregates of bacterial colonies embedded inside a self-produced polymeric matrix. Biofilms have received increasing attention in medical, industrial, and environmental settings due to their enhanced survival. Their characterization using microscopy techniques has revealed the presence of structural and cellular heterogeneity in many bacterial systems. However, these techniques provide limited chemical detail and lack information about the molecules important for bacterial communication and virulence. Mass spectrometry imaging (MSI) bridges the gap by generating spatial chemical information with unmatched chemical detail, making it an irreplaceable analytical platform in the multi-modal imaging of biofilms. In the last two decades, over 30 species of biofilm-forming bacteria have been studied using MSI in different environments. The literature conveys both analytical advancements and an improved understanding of the effects of environmental variables such as host surface characteristics, antibiotics, and other species of microorganisms on biofilms. This review summarizes the insights from frequently studied model microorganisms. We share a detailed list of organism-wide metabolites, commonly observed mass spectral adducts, culture conditions, strains of bacteria, substrate, broad problem definition, and details of the MS instrumentation, such as ionization sources and matrix, to facilitate future studies. We also compared the spatial characteristics of the secretome under different study designs to highlight changes because of various environmental influences. In addition, we highlight the current limitations of MSI in relation to biofilm characterization to enable cross-comparison between experiments. Overall, MSI has emerged to become an important approach for the spatial/chemical characterization of bacterial biofilms and its use will continue to grow as MSI becomes more accessible.
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Affiliation(s)
- Dharmeshkumar Parmar
- Department of Chemistry and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
| | - Joenisse M Rosado-Rosa
- Department of Chemistry and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States
| | - Joshua D Shrout
- Department of Civil and Environmental Engineering and Earth Sciences, University of Notre Dame, Notre Dame, IN 46556, United States; Department of Biological Sciences, University of Notre Dame, Notre Dame, IN 46556, United States
| | - Jonathan V Sweedler
- Department of Chemistry and Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign, Urbana, IL 61801, United States.
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Robertson SN, Soukarieh F, White TM, Camara M, Romero M, Griffiths RL. Probing Interkingdom Signaling Molecules via Liquid Extraction Surface Analysis-Mass Spectrometry. Anal Chem 2023; 95:5079-5086. [PMID: 36881460 PMCID: PMC10034741 DOI: 10.1021/acs.analchem.2c05703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
Abstract
Previously, metabolites diffused or secreted from microbial samples have been analyzed via liquid chromatography-mass spectrometry (LC-MS) approaches following lengthy extraction protocols. Here, we present a model system for growing biofilms on discs before utilizing rapid and direct surface sampling MS, namely, liquid extraction surface analysis, to study the microbial exometabolome. One of the benefits of this approach is its surface-specific nature, enabling mimicking biofilm formation in a way that the study of planktonic liquid cultures cannot imitate. Even though Pseudomonas aeruginosa (P. aeruginosa), Staphylococcus aureus (S. aureus), and Candida albicans (C. albicans) have been studied previously in isolation, very few studies consider the complexity of the interplay between these pathogens, which are commonly combined causative agents of infection. Our model system provides a route to investigate changes in the exometabolome, such as metabolites that become circulatory in the presence of multiple pathogens. Our results agree with previous reports showing that 2-alkyl-4(1H)-quinolone signal molecules produced by P. aeruginosa are important markers of infection and suggest that methods for monitoring levels of 2-heptyl-4-hydroxyquinoline and 2,4-dihydroxyquinoline, as well as pyocyanin, could be beneficial in the determination of causative agents in interkingdom infection including P. aeruginosa. Furthermore, studying changes in exometabolome metabolites between pqs quorum sensing antagonists in treated and nontreated samples suggests suppression of phenazine production by P. aeruginosa. Hence, our model provides a rapid analytical approach to gaining a mechanistic understanding of bacterial signaling.
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Affiliation(s)
- Shaun N Robertson
- U.K. National Biofilm Innovation Centre (NBIC), Biodiscovery Institute, School of Life Sciences, Faculty of Health and Medical Sciences, University of Nottingham, NG7 2RD Nottingham, U.K
| | - Fadi Soukarieh
- U.K. National Biofilm Innovation Centre (NBIC), Biodiscovery Institute, School of Life Sciences, Faculty of Health and Medical Sciences, University of Nottingham, NG7 2RD Nottingham, U.K
| | - Thomas M White
- Faculty of Science, School of Pharmacy, University of Nottingham, NG7 2RD Nottingham, U.K
| | - Miguel Camara
- U.K. National Biofilm Innovation Centre (NBIC), Biodiscovery Institute, School of Life Sciences, Faculty of Health and Medical Sciences, University of Nottingham, NG7 2RD Nottingham, U.K
| | - Manuel Romero
- U.K. National Biofilm Innovation Centre (NBIC), Biodiscovery Institute, School of Life Sciences, Faculty of Health and Medical Sciences, University of Nottingham, NG7 2RD Nottingham, U.K
- Department of Microbiology and Parasitology, Faculty of Biology-CIBUS, Universidade de Santiago de Compostela, 15782 Santiago de Compostela, Spain
| | - Rian L Griffiths
- Faculty of Science, School of Pharmacy, University of Nottingham, NG7 2RD Nottingham, U.K
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Mycelial differentiation linked avermectin production in Streptomyces avermitilis studied with Raman imaging. Appl Microbiol Biotechnol 2022; 107:369-378. [DOI: 10.1007/s00253-022-12314-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2022] [Revised: 11/21/2022] [Accepted: 11/24/2022] [Indexed: 12/12/2022]
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Li H, Li Z. The Exploration of Microbial Natural Products and Metabolic Interaction Guided by Mass Spectrometry Imaging. Bioengineering (Basel) 2022; 9:707. [PMID: 36421108 PMCID: PMC9687252 DOI: 10.3390/bioengineering9110707] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2022] [Revised: 11/02/2022] [Accepted: 11/12/2022] [Indexed: 10/17/2023] Open
Abstract
As an impressive mass spectrometry technology, mass spectrometric imaging (MSI) can provide mass spectra data and spatial distribution of analytes simultaneously. MSI has been widely used in diverse fields such as clinical diagnosis, the pharmaceutical industry and environmental study due to its accuracy, high resolution and developing reproducibility. Natural products (NPs) have been a critical source of leading drugs; almost half of marketed drugs are derived from NPs or their derivatives. The continuous search for bioactive NPs from microorganisms or microbiomes has always been attractive. MSI allows us to analyze and characterize NPs directly in monocultured microorganisms or a microbial community. In this review, we briefly introduce current mainstream ionization technologies for microbial samples and the key issue of sample preparation, and then summarize some applications of MSI in the exploration of microbial NPs and metabolic interaction, especially NPs from marine microbes. Additionally, remaining challenges and future prospects are discussed.
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Affiliation(s)
| | - Zhiyong Li
- State Key Laboratory of Microbial Metabolism, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
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5
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Jaisinghani N, Seeliger JC. Recent advances in the mass spectrometric profiling of bacterial lipids. Curr Opin Chem Biol 2021; 65:145-153. [PMID: 34600165 DOI: 10.1016/j.cbpa.2021.08.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 07/29/2021] [Accepted: 08/02/2021] [Indexed: 11/19/2022]
Abstract
Exploring the lipids of bacteria presents a predicament that may not be broadly recognized in a field dominated by the biology and biochemistry of eukaryotic - and especially, mammalian - lipids. Bacteria make multifarious metabolites that contain fatty acyl chains of unusual length and unsaturation attached to assorted headgroups, including sugars and fatty alcohols. Lipid profiling approaches developed for eukaryotic lipids often fail to detect, resolve, or identify bacterial lipids due to their wide range of polarities (including very hydrophobic species) and diverse positional and stereochemical variations. Global lipid profiling, or lipidomics, of bacteria has thus developed as a separate mission with methodological and scientific considerations tailored to the biology of these organisms. In this review, we summarize findings primarily from the last three years that exemplify recent advances and continuing challenges to learning about bacterial lipids.
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Affiliation(s)
- Neetika Jaisinghani
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY, 11794, USA
| | - Jessica C Seeliger
- Department of Pharmacological Sciences, Stony Brook University, Stony Brook, NY, 11794, USA.
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Methods for Studying Bacterial–Fungal Interactions in the Microenvironments of Soil. APPLIED SCIENCES-BASEL 2021. [DOI: 10.3390/app11199182] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Due to their small size, microorganisms directly experience only a tiny portion of the environmental heterogeneity manifested in the soil. The microscale variations in soil properties constrain the distribution of fungi and bacteria, and the extent to which they can interact with each other, thereby directly influencing their behavior and ecological roles. Thus, to obtain a realistic understanding of bacterial–fungal interactions, the spatiotemporal complexity of their microenvironments must be accounted for. The objective of this review is to further raise awareness of this important aspect and to discuss an overview of possible methodologies, some of easier applicability than others, that can be implemented in the experimental design in this field of research. The experimental design can be rationalized in three different scales, namely reconstructing the physicochemical complexity of the soil matrix, identifying and locating fungi and bacteria to depict their physical interactions, and, lastly, analyzing their molecular environment to describe their activity. In the long term, only relevant experimental data at the cell-to-cell level can provide the base for any solid theory or model that may serve for accurate functional prediction at the ecosystem level. The way to this level of application is still long, but we should all start small.
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Courrèges C, Bonnecaze M, Flahaut D, Nolivos S, Grimaud R, Allouche J. AES and ToF-SIMS combination for single cell chemical imaging of gold nanoparticle-labeled Escherichia coli. Chem Commun (Camb) 2021; 57:5446-5449. [PMID: 33950059 DOI: 10.1039/d1cc01211h] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A chemical fingerprint of the Escherichia coli cell surface labeled by gelatin coated gold nanoparticles was obtained by combining Auger Electron Spectroscopy (AES) for single cell level chemical images, and Time-of-Flight Secondary Ion Mass Spectroscopy (ToF-SIMS) Tandem MS for unambiguous molecular identification of co-localized species.
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Affiliation(s)
- Cécile Courrèges
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, Institut des Sciences Analytiques et Physico-Chimie Pour l'Environnement et les matériaux (IPREM), 2 avenue du Président Angot, 64000 Pau, France
| | - Mélanie Bonnecaze
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, Institut des Sciences Analytiques et Physico-Chimie Pour l'Environnement et les matériaux (IPREM), 2 avenue du Président Angot, 64000 Pau, France
| | - Delphine Flahaut
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, Institut des Sciences Analytiques et Physico-Chimie Pour l'Environnement et les matériaux (IPREM), 2 avenue du Président Angot, 64000 Pau, France
| | - Sophie Nolivos
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, Institut des Sciences Analytiques et Physico-chimie pour l'environnement et les matériaux (IPREM), Avenue de l'Université, 64000 Pau, France
| | - Régis Grimaud
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, Institut des Sciences Analytiques et Physico-chimie pour l'environnement et les matériaux (IPREM), Avenue de l'Université, 64000 Pau, France
| | - Joachim Allouche
- Université de Pau et des Pays de l'Adour, E2S UPPA, CNRS, Institut des Sciences Analytiques et Physico-Chimie Pour l'Environnement et les matériaux (IPREM), 2 avenue du Président Angot, 64000 Pau, France
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Sämfors S, Fletcher JS. Lipid Diversity in Cells and Tissue Using Imaging SIMS. ANNUAL REVIEW OF ANALYTICAL CHEMISTRY (PALO ALTO, CALIF.) 2020; 13:249-271. [PMID: 32212820 DOI: 10.1146/annurev-anchem-091619-103512] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
Lipids are an important class of biomolecules with many roles within cells and tissue. As targets for study, they present several challenges. They are difficult to label, as many labels lack the specificity to the many different lipid species or the labels maybe larger than the lipids themselves, thus severely perturbing the natural chemical environment. Mass spectrometry provides exceptional specificity and is often used to examine lipid extracts from different samples. However, spatial information is lost during extraction. Of the different imaging mass spectrometry methods available, secondary ion mass spectrometry (SIMS) is unique in its ability to analyze very small features, with probe sizes <50 nm available. It also offers high surface sensitivity and 3D imaging capability on a subcellular scale. This article reviews the current capabilities and some remaining challenges associated with imaging the diverse lipids present in cell and tissue samples. We show how the technique has moved beyond show-and-tell, proof-of-principle analysis and is now being used to address real biological challenges. These include imaging the microenvironment of cancer tumors, probing the pathophysiology of traumatic brain injury, or tracking the lipid composition through bacterial membranes.
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Affiliation(s)
- Sanna Sämfors
- Department of Chemistry and Molecular Biology, University of Gothenburg, 41296 Gothenburg, Sweden;
- Department of Chemistry and Chemical Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - John S Fletcher
- Department of Chemistry and Molecular Biology, University of Gothenburg, 41296 Gothenburg, Sweden;
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Giardina M, Cheong S, Marjo CE, Clode PL, Guagliardo P, Pickford R, Pernice M, Seymour JR, Raina JB. Quantifying Inorganic Nitrogen Assimilation by Synechococcus Using Bulk and Single-Cell Mass Spectrometry: A Comparative Study. Front Microbiol 2018; 9:2847. [PMID: 30538685 PMCID: PMC6277480 DOI: 10.3389/fmicb.2018.02847] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2018] [Accepted: 11/05/2018] [Indexed: 12/03/2022] Open
Abstract
Microorganisms drive most of the major biogeochemical cycles in the ocean, but the rates at which individual species assimilate and transform key elements is generally poorly quantified. One of these important elements is nitrogen, with its availability limiting primary production across a large proportion of the ocean. Nitrogen uptake by marine microbes is typically quantified using bulk-scale approaches, such as Elemental Analyzer-Isotope Ratio Mass Spectrometry (EA-IRMS), which averages uptake over entire communities, masking microbial heterogeneity. However, more recent techniques, such as secondary ion mass spectrometry (SIMS), allow for elucidation of assimilation rates at the scale at which they occur: the single-cell level. Here, we combine and compare the application of bulk (EA-IRMS) and single-cell approaches (NanoSIMS and Time-of-Flight-SIMS) for quantifying the assimilation of inorganic nitrogen by the ubiquitous marine primary producer Synechococcus. We aimed to contrast the advantages and disadvantages of these techniques and showcase their complementarity. Our results show that the average assimilation of 15N by Synechococcus differed based on the technique used: values derived from EA-IRMS were consistently higher than those derived from SIMS, likely due to a combination of previously reported systematic depletion as well as differences in sample preparation. However, single-cell approaches offered additional layers of information, whereby NanoSIMS allowed for the quantification of the metabolic heterogeneity among individual cells and ToF-SIMS enabled identification of nitrogen assimilation into peptides. We suggest that this coupling of stable isotope-based approaches has great potential to elucidate the metabolic capacity and heterogeneity of microbial cells in natural environments.
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Affiliation(s)
- Marco Giardina
- Climate Change Cluster, University of Technology Sydney, Sydney, NSW, Australia
| | - Soshan Cheong
- Mark Wainwright Analytical Centre, University of New South Wales, Kensington, NSW, Australia
| | - Christopher E. Marjo
- Mark Wainwright Analytical Centre, University of New South Wales, Kensington, NSW, Australia
| | - Peta L. Clode
- Centre for Microscopy Characterisation and Analysis, The University of Western Australia, Perth, WA, Australia
- UWA School of Biological Sciences, The University of Western Australia, Perth, WA, Australia
- UWA Oceans Institute, The University of Western Australia, Perth, WA, Australia
| | - Paul Guagliardo
- Centre for Microscopy Characterisation and Analysis, The University of Western Australia, Perth, WA, Australia
| | - Russell Pickford
- Bioanalytical Mass Spectrometry Facility, University of New South Wales, Sydney, NSW, Australia
| | - Mathieu Pernice
- Climate Change Cluster, University of Technology Sydney, Sydney, NSW, Australia
| | - Justin R. Seymour
- Climate Change Cluster, University of Technology Sydney, Sydney, NSW, Australia
| | - Jean-Baptiste Raina
- Climate Change Cluster, University of Technology Sydney, Sydney, NSW, Australia
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Hug JJ, Bader CD, Remškar M, Cirnski K, Müller R. Concepts and Methods to Access Novel Antibiotics from Actinomycetes. Antibiotics (Basel) 2018; 7:E44. [PMID: 29789481 PMCID: PMC6022970 DOI: 10.3390/antibiotics7020044] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2018] [Revised: 05/14/2018] [Accepted: 05/17/2018] [Indexed: 12/25/2022] Open
Abstract
Actinomycetes have been proven to be an excellent source of secondary metabolites for more than half a century. Exhibiting various bioactivities, they provide valuable approved drugs in clinical use. Most microorganisms are still untapped in terms of their capacity to produce secondary metabolites, since only a small fraction can be cultured in the laboratory. Thus, improving cultivation techniques to extend the range of secondary metabolite producers accessible under laboratory conditions is an important first step in prospecting underexplored sources for the isolation of novel antibiotics. Currently uncultured actinobacteria can be made available by bioprospecting extreme or simply habitats other than soil. Furthermore, bioinformatic analysis of genomes reveals most producers to harbour many more biosynthetic gene clusters than compounds identified from any single strain, which translates into a silent biosynthetic potential of the microbial world for the production of yet unknown natural products. This review covers discovery strategies and innovative methods recently employed to access the untapped reservoir of natural products. The focus is the order of actinomycetes although most approaches are similarly applicable to other microbes. Advanced cultivation methods, genomics- and metagenomics-based approaches, as well as modern metabolomics-inspired methods are highlighted to emphasise the interplay of different disciplines to improve access to novel natural products.
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Affiliation(s)
- Joachim J Hug
- Department Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI) and Department of Pharmacy, Saarland University, Campus E8.1, 66123 Saarbrücken, Germany.
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany.
| | - Chantal D Bader
- Department Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI) and Department of Pharmacy, Saarland University, Campus E8.1, 66123 Saarbrücken, Germany.
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany.
| | - Maja Remškar
- Department Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI) and Department of Pharmacy, Saarland University, Campus E8.1, 66123 Saarbrücken, Germany.
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany.
| | - Katarina Cirnski
- Department Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI) and Department of Pharmacy, Saarland University, Campus E8.1, 66123 Saarbrücken, Germany.
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany.
| | - Rolf Müller
- Department Microbial Natural Products, Helmholtz-Institute for Pharmaceutical Research Saarland (HIPS), Helmholtz Centre for Infection Research (HZI) and Department of Pharmacy, Saarland University, Campus E8.1, 66123 Saarbrücken, Germany.
- German Center for Infection Research (DZIF), Partner Site Hannover-Braunschweig, 38124 Braunschweig, Germany.
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High resolution imaging and 3D analysis of Ag nanoparticles in cells with ToF-SIMS and delayed extraction. Biointerphases 2018; 13:03B410. [PMID: 29490464 DOI: 10.1116/1.5015957] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Within this study, the authors use human mesenchymal stem cells incubated with silver nanoparticles (AgNPs) as a model system to systematically investigate the advantages and drawbacks of the fast imaging delayed extraction mode for two-dimensional and three-dimensional (3D) analyses at the cellular level. The authors compare the delayed extraction mode with commonly employed measurement modes in terms of mass and lateral resolution, intensity, and dose density. Using the delayed extraction mode for single cell analysis, a high mass resolution up to 4000 at m/z = 184.08 combined with a lateral resolution up to 360 nm is achieved. Furthermore, the authors perform 3D analyses with Ar-clusters (10 keV) and O2+ (500 eV) as sputter species, combined with Bi3+ and delayed extraction for analysis. Cell compartments like the nucleus are visualized in 3D, whereas no realistic 3D reconstruction of intracellular AgNP is possible due to the different sputter rates of inorganic and organic cell materials. Furthermore, the authors show that the sputter yield of Ag increases with the decreasing Ar-cluster size, which might be an approach to converge the different sputter rates.
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Visualizing Antimicrobials in Bacterial Biofilms: Three-Dimensional Biochemical Imaging Using TOF-SIMS. mSphere 2017; 2:mSphere00211-17. [PMID: 28744481 PMCID: PMC5518269 DOI: 10.1128/msphere.00211-17] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2017] [Accepted: 06/25/2017] [Indexed: 11/20/2022] Open
Abstract
Modern analytical techniques are becoming increasingly important in the life sciences; imaging mass spectrometry offers the opportunity to gain unprecedented amounts of information on the distribution of chemicals in samples—both xenobiotics and endogenous compounds. In particular, simultaneous imaging of antibiotics (and other antimicrobial compounds) and bacterium-derived metabolites in complex biological samples could be very important in the future for helping to understand how sample matrices impact the survival of bacteria under antibiotic challenge. We have shown that an imaging mass spectrometric technique, TOF-SIMS, will be potentially extremely valuable for this kind of research in the future. Bacterial biofilms are groups of bacteria that exist within a self-produced extracellular matrix, adhering to each other and usually to a surface. They grow on medical equipment and inserts such as catheters and are responsible for many persistent infections throughout the body, as they can have high resistance to many antimicrobials. Pseudomonas aeruginosa is an opportunistic pathogen that can cause both acute and chronic infections and is used as a model for research into biofilms. Direct biochemical methods of imaging of molecules in bacterial biofilms are of high value in gaining a better understanding of the fundamental biology of biofilms and biochemical gradients within them. Time of flight–secondary-ion mass spectrometry (TOF-SIMS) is one approach, which combines relatively high spatial resolution and sensitivity and can perform depth profiling analysis. It has been used to analyze bacterial biofilms but has not yet been used to study the distribution of antimicrobials (including antibiotics and the antimicrobial metal gallium) within biofilms. Here we compared two methods of imaging of the interior structure of P. aeruginosa in biological samples using TOF-SIMS, looking at both antimicrobials and endogenous biochemicals: cryosectioning of tissue samples and depth profiling to give pseudo-three-dimensional (pseudo-3D) images. The sample types included both simple biofilms grown on glass slides and bacteria growing in tissues in an ex vivo pig lung model. The two techniques for the 3D imaging of biofilms are potentially valuable complementary tools for analyzing bacterial infection. IMPORTANCE Modern analytical techniques are becoming increasingly important in the life sciences; imaging mass spectrometry offers the opportunity to gain unprecedented amounts of information on the distribution of chemicals in samples—both xenobiotics and endogenous compounds. In particular, simultaneous imaging of antibiotics (and other antimicrobial compounds) and bacterium-derived metabolites in complex biological samples could be very important in the future for helping to understand how sample matrices impact the survival of bacteria under antibiotic challenge. We have shown that an imaging mass spectrometric technique, TOF-SIMS, will be potentially extremely valuable for this kind of research in the future.
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Covington BC, McLean JA, Bachmann BO. Comparative mass spectrometry-based metabolomics strategies for the investigation of microbial secondary metabolites. Nat Prod Rep 2017; 34:6-24. [PMID: 27604382 PMCID: PMC5214543 DOI: 10.1039/c6np00048g] [Citation(s) in RCA: 87] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
Covering: 2000 to 2016The labor-intensive process of microbial natural product discovery is contingent upon identifying discrete secondary metabolites of interest within complex biological extracts, which contain inventories of all extractable small molecules produced by an organism or consortium. Historically, compound isolation prioritization has been driven by observed biological activity and/or relative metabolite abundance and followed by dereplication via accurate mass analysis. Decades of discovery using variants of these methods has generated the natural pharmacopeia but also contributes to recent high rediscovery rates. However, genomic sequencing reveals substantial untapped potential in previously mined organisms, and can provide useful prescience of potentially new secondary metabolites that ultimately enables isolation. Recently, advances in comparative metabolomics analyses have been coupled to secondary metabolic predictions to accelerate bioactivity and abundance-independent discovery work flows. In this review we will discuss the various analytical and computational techniques that enable MS-based metabolomic applications to natural product discovery and discuss the future prospects for comparative metabolomics in natural product discovery.
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Affiliation(s)
- Brett C Covington
- Department of Chemistry, Vanderbilt University, 7330 Stevenson Center, Nashville, TN 37235, USA.
| | - John A McLean
- Department of Chemistry, Vanderbilt University, 7330 Stevenson Center, Nashville, TN 37235, USA. and Center for Innovative Technology, Vanderbilt University, 5401 Stevenson Center, Nashville, TN 37235, USA
| | - Brian O Bachmann
- Department of Chemistry, Vanderbilt University, 7330 Stevenson Center, Nashville, TN 37235, USA.
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Metal-assisted polyatomic SIMS and laser desorption/ionization for enhanced small molecule imaging of bacterial biofilms. Biointerphases 2016; 11:02A325. [PMID: 26945568 DOI: 10.1116/1.4942884] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023] Open
Abstract
Mass spectrometry imaging (MSI) has become an important analytical tool for many sectors of science and medicine. As the application of MSI expands into new areas of inquiry, existing methodologies must be adapted and improved to meet emerging challenges. Particularly salient is the need for small molecule imaging methods that are compatible with complex multicomponent systems, a challenge that is amplified by the effects of analyte migration and matrix interference. With a focus on microbial biofilms from the opportunistic pathogen Pseudomonas aeruginosa, the relative advantages of two established microprobe-based MSI techniques-polyatomic secondary ion mass spectrometry (SIMS) and laser desorption/ionization-are compared, with emphasis on exploring the effect of surface metallization on small molecule imaging. A combination of qualitative image comparison and multivariate statistical analysis demonstrates that sputtering microbial biofilms with a 2.5 nm layer of gold selectively enhances C60-SIMS ionization for several molecular classes including rhamnolipids and 2-alkyl-quinolones. Metallization also leads to the reduction of in-source fragmentation and subsequent ionization of media-specific background polymers, which improves spectral purity and image quality. These findings show that the influence of metallization upon ionization is strongly dependent on both the surface architecture and the analyte class, and further demonstrate that metal-assisted C60-SIMS is a viable method for small molecule imaging of intact molecular ions in complex biological systems.
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Abstract
Time-of-flight secondary ion mass spectrometry (ToF-SIMS) is a rapidly developing technique for the characterization of a wide range of materials. Recently, advances in instrumentation and sample preparation approaches have provided the ability to perform 3D molecular imaging experiments. Polyatomic ion beams, such as C60, and gas cluster ion beams, often Arn (n = 500-4000), substantially reduce the subsurface damage accumulation associated with continued bombardment of organic samples with atomic beams. In this review, the capabilities of the technique are discussed and examples of the 3D imaging approach for the analysis of model membrane systems, plant single cell, and tissue samples are presented. Ongoing challenges for 3D ToF-SIMS imaging are also discussed along with recent developments that might offer improved 3D imaging prospects in the near future.
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16
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Aram P, Shen L, Pugh JA, Vaidyanathan S, Kadirkamanathan V. An efficient TOF-SIMS image analysis with spatial correlation and alternating non-negativity-constrained least squares. ACTA ACUST UNITED AC 2014; 31:753-60. [PMID: 25452330 DOI: 10.1093/bioinformatics/btu734] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023]
Abstract
MOTIVATION Advances in analytical instrumentation towards acquiring high-resolution images of mass spectrometry constantly demand efficient approaches for data analysis. This is particularly true of time-of-flight secondary ion mass spectrometry imaging where recent advances enable acquisition of high-resolution data in multiple dimensions. In many applications, the distribution of different species from a sampled surface is spatially continuous in nature and a model that incorporates the spatial correlation across the surface would be preferable to estimations at discrete spatial locations. A key challenge here is the capability to analyse the high-resolution multidimensional data to extract relevant information reliably and efficiently. RESULTS We propose a framework based on alternating non-negativity-constrained least squares which accounts for the spatial correlation across the sample surface. The proposed method also decouples the computational complexity of the estimation procedure from the image resolution, which significantly reduces the processing time. We evaluate the performance of the algorithm with biochemical image datasets generated from mixture of metabolites.
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Affiliation(s)
- Parham Aram
- Department of Automatic Control and Systems Engineering and Department of Chemical and Biological Engineering, University of Sheffield, Sheffield, UK
| | - Lingli Shen
- Department of Automatic Control and Systems Engineering and Department of Chemical and Biological Engineering, University of Sheffield, Sheffield, UK
| | - John A Pugh
- Department of Automatic Control and Systems Engineering and Department of Chemical and Biological Engineering, University of Sheffield, Sheffield, UK
| | - Seetharaman Vaidyanathan
- Department of Automatic Control and Systems Engineering and Department of Chemical and Biological Engineering, University of Sheffield, Sheffield, UK
| | - Visakan Kadirkamanathan
- Department of Automatic Control and Systems Engineering and Department of Chemical and Biological Engineering, University of Sheffield, Sheffield, UK
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17
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Lanni EJ, Masyuko R, Driscoll CM, Aerts JT, Shrout JD, Bohn PW, Sweedler JV. MALDI-guided SIMS: multiscale imaging of metabolites in bacterial biofilms. Anal Chem 2014; 86:9139-45. [PMID: 25133532 PMCID: PMC4165220 DOI: 10.1021/ac5020222] [Citation(s) in RCA: 64] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2014] [Accepted: 08/18/2014] [Indexed: 12/21/2022]
Abstract
Mass spectrometry imaging (MSI) is a versatile tool for visualizing molecular distributions in complex biological specimens, but locating microscopic chemical features of interest can be challenging in samples that lack a well-defined anatomy. To address this issue, we developed a correlated imaging approach that begins with performing matrix-assisted laser desorption/ionization (MALDI) MSI to obtain low-resolution molecular maps of a sample. The resulting maps are then used to direct subsequent microscopic secondary ion mass spectrometry (SIMS) imaging and tandem mass spectrometry (MS/MS) experiments to examine selected chemical regions of interest. By employing MALDI undersampling, the sample surface is left mostly unperturbed and available for the SIMS analysis, while also generating an ablation array that can be used for navigation in SIMS. We validated this MALDI-guided SIMS approach using cultured biofilms of the opportunistic pathogen Pseudomonas aeruginosa; bioactive secondary metabolites, including rhamnolipids and quinolones, were detected and visualized on both macro- and microscopic size scales. MSI mass assignments were confirmed with in situ MALDI MS/MS and capillary electrophoresis-electrospray ionization MS/MS analysis of biofilm extracts. Two strains of P. aeruginosa were compared, wild type and a quorum sensing mutant, and differences in metabolite abundance and distribution were observed.
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Affiliation(s)
- Eric J. Lanni
- Department
of Chemistry and Beckman Institute for Advanced Science
and Technology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Rachel
N. Masyuko
- Department of Chemistry and Biochemistry and Department
of Chemical
and Biomolecular Engineering, and Department of Civil and Environmental Engineering
and Earth Sciences and Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Callan M. Driscoll
- Department of Chemistry and Biochemistry and Department
of Chemical
and Biomolecular Engineering, and Department of Civil and Environmental Engineering
and Earth Sciences and Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Jordan T. Aerts
- Department
of Chemistry and Beckman Institute for Advanced Science
and Technology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
| | - Joshua D. Shrout
- Department of Chemistry and Biochemistry and Department
of Chemical
and Biomolecular Engineering, and Department of Civil and Environmental Engineering
and Earth Sciences and Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Paul W. Bohn
- Department of Chemistry and Biochemistry and Department
of Chemical
and Biomolecular Engineering, and Department of Civil and Environmental Engineering
and Earth Sciences and Department of Biological Sciences, University of Notre Dame, Notre Dame, Indiana 46556, United States
| | - Jonathan V. Sweedler
- Department
of Chemistry and Beckman Institute for Advanced Science
and Technology, University of Illinois at Urbana−Champaign, Urbana, Illinois 61801, United States
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18
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Bouslimani A, Sanchez LM, Garg N, Dorrestein PC. Mass spectrometry of natural products: current, emerging and future technologies. Nat Prod Rep 2014; 31:718-29. [PMID: 24801551 PMCID: PMC4161218 DOI: 10.1039/c4np00044g] [Citation(s) in RCA: 134] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Although mass spectrometry is a century old technology, we are entering into an exciting time for the analysis of molecular information directly from complex biological systems. In this Highlight, we feature emerging mass spectrometric methods and tools used by the natural product community and give a perspective of future directions where the mass spectrometry field is migrating towards over the next decade.
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Affiliation(s)
- Amina Bouslimani
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California San Diego, La Jolla, California 92093, United States
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19
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Masyuko RN, Lanni EJ, Driscoll CM, Shrout JD, Sweedler JV, Bohn PW. Spatial organization of Pseudomonas aeruginosa biofilms probed by combined matrix-assisted laser desorption ionization mass spectrometry and confocal Raman microscopy. Analyst 2014; 139:5700-8. [DOI: 10.1039/c4an00435c] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
The chemical composition of bacterial biofilms is explored and visualized with the combination of two label-free molecular imaging techniques.
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Affiliation(s)
- Rachel N. Masyuko
- Department of Chemistry and Biochemistry
- University of Notre Dame
- Notre Dame, USA
| | - Eric J. Lanni
- Department of Chemistry
- University of Illinois at Urbana-Champaign
- Urbana, USA
| | - Callan M. Driscoll
- Department of Civil and Environmental Engineering and Earth Sciences
- University of Notre Dame
- Notre Dame, USA
| | - Joshua D. Shrout
- Department of Civil and Environmental Engineering and Earth Sciences
- University of Notre Dame
- Notre Dame, USA
| | | | - Paul W. Bohn
- Department of Chemistry and Biochemistry
- University of Notre Dame
- Notre Dame, USA
- Department of Chemical and Biomolecular Engineering
- University of Notre Dame
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20
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Shih CJ, Chen PY, Liaw CC, Lai YM, Yang YL. Bringing microbial interactions to light using imaging mass spectrometry. Nat Prod Rep 2014; 31:739-55. [DOI: 10.1039/c3np70091g] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
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21
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Watrous JD, Phelan VV, Hsu CC, Moree WJ, Duggan BM, Alexandrov T, Dorrestein PC. Microbial metabolic exchange in 3D. THE ISME JOURNAL 2013; 7:770-80. [PMID: 23283018 PMCID: PMC3603389 DOI: 10.1038/ismej.2012.155] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2012] [Revised: 10/12/2012] [Accepted: 10/26/2012] [Indexed: 01/14/2023]
Abstract
Mono- and multispecies microbial populations alter the chemistry of their surrounding environments during colony development thereby influencing multicellular behavior and interspecies interactions of neighboring microbes. Here we present a methodology that enables the creation of three-dimensional (3D) models of a microbial chemotype that can be correlated to the colony phenotype through multimodal imaging analysis. These models are generated by performing matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) imaging mass spectrometry (IMS) on serial cross-sections of microbial colonies grown on 8 mm deep agar, registering data sets of each serial section in MATLAB to create a model, and then superimposing the model with a photograph of the colonies themselves. As proof-of-principle, 3D models were used to visualize metabolic exchange during microbial interactions between Bacillus subtilis and Streptomyces coelicolor, as well as, Candida albicans and Pseudomonas aeruginosa. The resulting models were able to capture the depth profile of secreted metabolites within the agar medium and revealed properties of certain mass signals that were previously not observable using two-dimensional MALDI-TOF IMS. Most significantly, the 3D models were capable of mapping previously unobserved chemical distributions within the array of sub-surface hyphae of C. albicans and how this chemistry is altered by the presence of P. aeruginosa, an opportunistic pathogen known to alter virulence of C. albicans. It was determined that the presence of C. albicans triggered increased rhamnolipid production by P. aeruginosa, which in turn was capable of inhibiting embedded hyphal growth produced beneath the C. albicans colony at ambient temperature.
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Affiliation(s)
- Jeramie D Watrous
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Vanessa V Phelan
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Cheng-Chih Hsu
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - Wilna J Moree
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Brendan M Duggan
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
| | - Theodore Alexandrov
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
- Center for Industrial Mathematics, University of Bremen, Bremen, Germany
| | - Pieter C Dorrestein
- Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, CA, USA
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, CA, USA
- Department of Pharmacology, University of California, San Diego, La Jolla, CA, USA
- Center for Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography, La Jolla, CA, USA
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22
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Liao HY, Lin KY, Kao WL, Chang HY, Huang CC, Shyue JJ. Enhancing the Sensitivity of Molecular Secondary Ion Mass Spectrometry with C60+-O2+ Cosputtering. Anal Chem 2013; 85:3781-8. [DOI: 10.1021/ac400214t] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Hua-Yang Liao
- Research Center for Applied
Science, Academia Sinica, Tapei 115, Taiwan
| | - Kang-Yi Lin
- Research Center for Applied
Science, Academia Sinica, Tapei 115, Taiwan
| | - Wei-Lun Kao
- Research Center for Applied
Science, Academia Sinica, Tapei 115, Taiwan
| | - Hsun-Yun Chang
- Research Center for Applied
Science, Academia Sinica, Tapei 115, Taiwan
- Nanoscience
and Technology Program,
Taiwan International Graduate Program, Academia Sinica, Taipei 115, Taiwan
- Department
of Engineering and
System Science, National Tsing Hua University, Hsin-Chu, 300, Taiwan
| | - Chih-Chieh Huang
- Department of Materials Science
and Engineering, Nation Taiwan University, Taipei 106, Taiwan
| | - Jing-Jong Shyue
- Research Center for Applied
Science, Academia Sinica, Tapei 115, Taiwan
- Department of Materials Science
and Engineering, Nation Taiwan University, Taipei 106, Taiwan
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23
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Tejero R, Rossbach P, Keller B, Anitua E, Reviakine I. Time-of-flight secondary ion mass spectrometry with principal component analysis of titania-blood plasma interfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2013; 29:902-912. [PMID: 23095019 DOI: 10.1021/la303360f] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
Treatment of osseoimplant surfaces with autologous platelet-rich plasma prepared according to the plasma rich in growth factors (PRGF-Endoret) protocol prior to implantation yields promising results in the clinic. Our objective is to understand the organization of complex interfaces between blood plasma preparations of various compositions and model titania surfaces. Here we present the results of the morphological and chemical characterization of TiO(2) surfaces incubated with four types of blood plasma preparations devoid of leukocytes and red blood cells: either enriched in platelets (PRGF-Endoret) or platelet-depleted, and either activated with CaCl(2) to induce clotting, or not. Chemical characterization was done by time-of-flight secondary ion mass spectrometry with principal component analysis (ToF-SIMS/PCA). The interface morphology was studied with scanning electron and atomic force microscopy. Immunofluorescence microscopy was used to identify platelets and infer their activation state. We observe clear differences among the four types of interfaces by ToF-SIMS/PCA. Some of these could be straightforwardly related to the differences in the sample morphology and known effects of platelet activation, but others are more subtle. Strikingly, it was possible to differentiate between these samples by ToF-SIMS/PCA of the protein species alone. This clearly indicates that the composition, orientation, and/or conformation of the proteins in these specimens depend both on the platelets' presence and on their activation. The ToF-SIMS imaging functionality furthermore provides unique insight into the distribution of phospholipid species in these samples.
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24
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Affiliation(s)
- Seetharaman Vaidyanathan
- ChELSI Institute, Department of Chemical and Biological Engineering; The University of Sheffield; Mappin Street Sheffield S1 3JD
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25
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Konicek AR, Lefman J, Szakal C. Automated correlation and classification of secondary ion mass spectrometry images using a k-means cluster method. Analyst 2012; 137:3479-87. [PMID: 22567660 DOI: 10.1039/c2an16122b] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
We present a novel method for correlating and classifying ion-specific time-of-flight secondary ion mass spectrometry (ToF-SIMS) images within a multispectral dataset by grouping images with similar pixel intensity distributions. Binary centroid images are created by employing a k-means-based custom algorithm. Centroid images are compared to grayscale SIMS images using a newly developed correlation method that assigns the SIMS images to classes that have similar spatial (rather than spectral) patterns. Image features of both large and small spatial extent are identified without the need for image pre-processing, such as normalization or fixed-range mass-binning. A subsequent classification step tracks the class assignment of SIMS images over multiple iterations of increasing n classes per iteration, providing information about groups of images that have similar chemistry. Details are discussed while presenting data acquired with ToF-SIMS on a model sample of laser-printed inks. This approach can lead to the identification of distinct ion-specific chemistries for mass spectral imaging by ToF-SIMS, as well as matrix-assisted laser desorption ionization (MALDI), and desorption electrospray ionization (DESI).
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Affiliation(s)
- Andrew R Konicek
- Surface and Microanalysis Science Division, National Institute of Standards and Technology, Gaithersburg, MD, USA
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26
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Lanni EJ, Rubakhin SS, Sweedler JV. Mass spectrometry imaging and profiling of single cells. J Proteomics 2012; 75:5036-5051. [PMID: 22498881 DOI: 10.1016/j.jprot.2012.03.017] [Citation(s) in RCA: 137] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2011] [Revised: 03/08/2012] [Accepted: 03/13/2012] [Indexed: 11/25/2022]
Abstract
Mass spectrometry imaging and profiling of individual cells and subcellular structures provide unique analytical capabilities for biological and biomedical research, including determination of the biochemical heterogeneity of cellular populations and intracellular localization of pharmaceuticals. Two mass spectrometry technologies-secondary ion mass spectrometry (SIMS) and matrix assisted laser desorption/ionization mass spectrometry (MALDI MS)-are most often used in micro-bioanalytical investigations. Recent advances in ion probe technologies have increased the dynamic range and sensitivity of analyte detection by SIMS, allowing two- and three-dimensional localization of analytes in a variety of cells. SIMS operating in the mass spectrometry imaging (MSI) mode can routinely reach spatial resolutions at the submicron level; therefore, it is frequently used in studies of the chemical composition of subcellular structures. MALDI MS offers a large mass range and high sensitivity of analyte detection. It has been successfully applied in a variety of single-cell and organelle profiling studies. Innovative instrumentation such as scanning microprobe MALDI and mass microscope spectrometers enables new subcellular MSI measurements. Other approaches for MS-based chemical imaging and profiling include those based on near-field laser ablation and inductively-coupled plasma MS analysis, which offer complementary capabilities for subcellular chemical imaging and profiling.
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Affiliation(s)
- Eric J Lanni
- Department of Chemistry and the Beckman Institute of Science and Technology, University of Illinois, Urbana IL 61801, USA
| | - Stanislav S Rubakhin
- Department of Chemistry and the Beckman Institute of Science and Technology, University of Illinois, Urbana IL 61801, USA
| | - Jonathan V Sweedler
- Department of Chemistry and the Beckman Institute of Science and Technology, University of Illinois, Urbana IL 61801, USA.
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27
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Vaidyanathan S, Salim M, Hurley C, Pugh J. Vapour-mediated ion activation for enhanced SIMS imaging. SURF INTERFACE ANAL 2012. [DOI: 10.1002/sia.4883] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Seetharaman Vaidyanathan
- Department of Chemical and Biological Engineering, ChELSI Institute; The University of Sheffield; Mappin Street; Sheffield; S1 3JD; UK
| | - Malinda Salim
- Department of Chemical and Biological Engineering, ChELSI Institute; The University of Sheffield; Mappin Street; Sheffield; S1 3JD; UK
| | - Claire Hurley
- Department of Chemistry; The University of Sheffield; Mappin Street; Sheffield; S1 3JD; UK
| | - John Pugh
- Department of Chemical and Biological Engineering, ChELSI Institute; The University of Sheffield; Mappin Street; Sheffield; S1 3JD; UK
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28
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Abstract
Imaging mass spectrometry tools allow the two-dimensional visualization of the distribution of trace metals, metabolites, surface lipids, peptides and proteins directly from biological samples without the need for chemical tagging or antibodies, and are becoming increasingly useful for microbiology applications. These tools, comprising different imaging mass spectrometry techniques, are ushering in an exciting new era of discovery by enabling the generation of chemical hypotheses based on the spatial mapping of atoms and molecules that can correlate to or transcend observed phenotypes. In this Innovation article, we explore the wide range of imaging mass spectrometry techniques that is available to microbiologists and describe the unique applications of these tools to microbiology with respect to the types of samples to be investigated.
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Affiliation(s)
- Jeramie D. Watrous
- Department of Pharmacology and Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California, USA
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California, USA
| | - Pieter C. Dorrestein
- Department of Pharmacology and Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California, USA
- Skaggs School of Pharmacy and Pharmaceutical Sciences, University of California, San Diego, La Jolla, California, USA
- Center For Marine Biotechnology and Biomedicine, Scripps Institution of Oceanography
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29
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Effect of sample rotation on surface roughness with keV C60 bombardment in secondary ion mass spectrometry (SIMS) experiments. Chem Phys Lett 2011. [DOI: 10.1016/j.cplett.2011.03.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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30
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Gasper GL, Takahashi LK, Zhou J, Ahmed M, Moore JF, Hanley L. Laser desorption postionization mass spectrometry of antibiotic-treated bacterial biofilms using tunable vacuum ultraviolet radiation. Anal Chem 2011; 82:7472-8. [PMID: 20712373 DOI: 10.1021/ac101667q] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Laser desorption postionization mass spectrometry (LDPI-MS) with 8.0-12.5 eV vacuum ultraviolet synchrotron radiation is used to single photon ionize antibiotics and extracellular neutrals that are laser desorbed both from neat and intact bacterial biofilms. Neat antibiotics are optimally detected using 10.5 eV LDPI-MS but can be ionized using 8.0 eV radiation, in agreement with prior work using 7.87 eV LDPI-MS. Tunable vacuum ultraviolet radiation also postionizes laser desorbed neutrals of antibiotics and extracellular material from within intact bacterial biofilms. Different extracellular material is observed by LDPI-MS in response to rifampicin or trimethoprim antibiotic treatment. Once again, 10.5 eV LDPI-MS displays the optimum trade-off between improved sensitivity and minimum fragmentation. Higher energy photons at 12.5 eV produce significant parent ion signal, but fragment intensity and other low mass ions are also enhanced. No matrix is added to enhance desorption, which is performed at peak power densities insufficient to directly produce ions, thus allowing observation of true VUV postionization mass spectra of antibiotic treated biofilms.
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Affiliation(s)
- Gerald L Gasper
- Department of Chemistry, University of Illinois at Chicago, Chicago, Illinois 60607, USA
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31
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Lee PL, Shen SY, Yin YS, Lei SL, Jhang CL, Lee WR, Ling YC. ToF-SIMS Imaging of Intracellular 39K/ 40Ca Changes induced by ZnO-containing Nanomaterials. ACTA ACUST UNITED AC 2011. [DOI: 10.1384/jsa.17.305] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Affiliation(s)
- Pei-Ling Lee
- Department of Chemistry, National Tsing Hua University
- Biomedical Mass Imaging Research Center, Taipei Medical University
| | - Sin-Yu Shen
- Graduate Institute of Medical Science, Taipei Medical University
| | - Yu-Sheng Yin
- Department of Chemistry, National Tsing Hua University
| | - Shiu-Ling Lei
- Department of Chemistry, National Tsing Hua University
| | | | - Woan-Ruoh Lee
- Department of Dermatology, Taipei Medical University
| | - Yong-Chien Ling
- Department of Chemistry, National Tsing Hua University
- Biomedical Mass Imaging Research Center, Taipei Medical University
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32
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Vickerman JC. Molecular imaging and depth profiling by mass spectrometry—SIMS, MALDI or DESI? Analyst 2011; 136:2199-217. [DOI: 10.1039/c1an00008j] [Citation(s) in RCA: 159] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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33
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Fletcher JS, Lockyer NP, Vickerman JC. Developments in molecular SIMS depth profiling and 3D imaging of biological systems using polyatomic primary ions. MASS SPECTROMETRY REVIEWS 2011; 30:142-74. [PMID: 20077559 DOI: 10.1002/mas.20275] [Citation(s) in RCA: 71] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In principle mass spectral imaging has enormous potential for discovery applications in biology. The chemical specificity of mass spectrometry combined with spatial analysis capabilities of liquid metal cluster beams and the high yields of polyatomic ion beams should present unprecedented ability to spatially locate molecular chemistry in the 100 nm range. However, although metal cluster ion beams have greatly increased yields in the m/z range up to 1000, they still have to be operated under the static limit and even in most favorable cases maximum yields for molecular species from 1 µm pixels are frequently below 20 counts. However, some very impressive molecular imaging analysis has been accomplished under these conditions. Nevertheless although molecular ions of lipids have been detected and correlation with biology is obtained, signal levels are such that lateral resolution must be sacrificed to provide a sufficient signal to image. To obtain useful spatial resolution detection below 1 µm is almost impossible. Too few ions are generated! The review shows that the application of polyatomic primary ions with their low damage cross-sections offers hope of a new approach to molecular SIMS imaging by accessing voxels rather than pixels to thereby increase the dynamic signal range in 2D imaging and to extend the analysis to depth profiling and 3D imaging. Recent data on cells and tissue analysis suggest that there is, in consequence, the prospect that a wider chemistry might be accessible within a sub-micron area and as a function of depth. However, these advances are compromised by the pulsed nature of current ToF-SIMS instruments. The duty cycle is very low and results in excessive analysis times, and maximum mass resolution is incompatible with maximum spatial resolution. New instrumental directions are described that enable a dc primary beam to be used that promises to be able to take full advantage of all the capabilities of the polyatomic ion beam. Some new data are presented that suggest that the aspirations for these new instruments will be realized. However, although prospects are good, the review highlights the continuing challenges presented by the low ionization efficiency and the complications that arise from matrix effects.
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Affiliation(s)
- John S Fletcher
- Manchester Interdisciplinary Biocentre, School of Chemical Engineering and Analytical Science, University of Manchester, Manchester M60 1QD, UK
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34
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Huang X, Song F, Liu Z, Liu S, Ai J. Comprehensive quality evaluation of Fructus Schisandrae using electrospray ionization ion trap multiple-stage tandem mass spectrometry coupled with chemical pattern recognition techniques. Analyst 2011; 136:4308-15. [DOI: 10.1039/c1an15527j] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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35
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Tuccitto N, Marletta G, Carnazza S, Grasso L, Caratozzolo M, Guglielmino S, Licciardello A. ToF-SIMS imaging of surface self-organized fractal patterns of bacteria. SURF INTERFACE ANAL 2010. [DOI: 10.1002/sia.3555] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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36
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Wucher A, Winograd N. Molecular sputter depth profiling using carbon cluster beams. Anal Bioanal Chem 2010; 396:105-14. [PMID: 19649771 PMCID: PMC2863088 DOI: 10.1007/s00216-009-2971-x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2009] [Revised: 07/09/2009] [Accepted: 07/09/2009] [Indexed: 11/28/2022]
Abstract
Sputter depth profiling of organic films while maintaining the molecular integrity of the sample has long been deemed impossible because of the accumulation of ion bombardment-induced chemical damage. Only recently, it was found that this problem can be greatly reduced if cluster ion beams are used for sputter erosion. For organic samples, carbon cluster ions appear to be particularly well suited for such a task. Analysis of available data reveals that a projectile appears to be more effective as the number of carbon atoms in the cluster is increased, leaving fullerene ions as the most promising candidates to date. Using a commercially available, highly focused C (60) (q+) cluster ion beam, we demonstrate the versatility of the technique for depth profiling various organic films deposited on a silicon substrate and elucidate the dependence of the results on properties such as projectile ion impact energy and angle, and sample temperature. Moreover, examples are shown where the technique is applied to organic multilayer structures in order to investigate the depth resolution across film-film interfaces. These model experiments allow collection of valuable information on how cluster impact molecular depth profiling works and how to understand and optimize the depth resolution achieved using this technique.
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Affiliation(s)
- Andreas Wucher
- Fakultät für Physik, Universität Duisburg-Essen, 47048, Duisburg, Germany.
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37
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Yang YL, Xu Y, Straight P, Dorrestein PC. Translating metabolic exchange with imaging mass spectrometry. Nat Chem Biol 2009; 5:885-7. [PMID: 19915536 PMCID: PMC2778862 DOI: 10.1038/nchembio.252] [Citation(s) in RCA: 200] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2009] [Accepted: 09/10/2009] [Indexed: 12/18/2022]
Abstract
Metabolic exchange between an organism and the environment, including interactions with neighboring organisms, is important for processes of organismal development. Here we develop and use thin-layer agar natural product MALDI-TOF imaging mass spectrometry of intact bacterial colonies grown on top of the MALDI target plate to study an interaction between two species of bacteria and provide direct evidence that a Bacillus subtilis silences the defensive arsenal of Streptomyces coelicolor.
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38
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Zhu Z, Nachimuthu P, Lea AS. Molecular Depth Profiling of Sucrose Films: A Comparative Study of C60n+ Ions and Traditional Cs+ and O2+ Ions. Anal Chem 2009; 81:8272-9. [DOI: 10.1021/ac900553z] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Zihua Zhu
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352
| | - Ponnusamy Nachimuthu
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352
| | - Alan S. Lea
- Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, P.O. Box 999, Richland, Washington 99352
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39
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Fletcher JS, Vickerman JC. A new SIMS paradigm for 2D and 3D molecular imaging of bio-systems. Anal Bioanal Chem 2009; 396:85-104. [PMID: 19669735 DOI: 10.1007/s00216-009-2986-3] [Citation(s) in RCA: 86] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2009] [Accepted: 07/13/2009] [Indexed: 11/28/2022]
Abstract
With the implementation of focused primary ion beams, secondary ion mass spectrometry (SIMS) has become a significant technique in the rapidly emerging field of mass spectral imaging in the biological sciences. Liquid metal ion guns (LMIG) offered the prospect of sub-100 nm spatial resolution, however this aspiration has yet to be reached for molecular imaging. This brief review shows that using LMIG the limitations of the static limit and low ionization probability will restrict useful imaging to around 2 mum spatial resolution with high-yield molecules. The only prospect of going beyond this in the absence of factors of 100 increase in ionization probability is to use polyatomic ion beams such as C (60) (+) , for which bombardment induced damage is low. In these cases sub-micron imaging becomes possible, using voxels together with molecular depth profiling and 3D imaging. The discussion shows that conventional ToF-SIMS instrumentation then becomes a limitation in that the pulsed ion beam has a very low duty cycle which results in inordinately long analysis times, and pulsing the beam means that high-mass resolution and high spatial resolution are mutually incompatible. New instrumental configurations are described that allow the use of a dc ion beam and separate the mass spectrometry for the ion formation process. Early results from these instruments suggest that sub-micron analysis and imaging with high mass resolution and good ion yields are now realizable, although the low ion yield issue still needs to be solved.
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Affiliation(s)
- John S Fletcher
- Manchester Interdisciplinary Biocentre, School of Chemical Engineering and Analytical Science, The University of Manchester, Manchester, M1 7DN, UK
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Desorption electrospray ionization mass spectrometry reveals surface-mediated antifungal chemical defense of a tropical seaweed. Proc Natl Acad Sci U S A 2009; 106:7314-9. [PMID: 19366672 DOI: 10.1073/pnas.0812020106] [Citation(s) in RCA: 172] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Organism surfaces represent signaling sites for attraction of allies and defense against enemies. However, our understanding of these signals has been impeded by methodological limitations that have precluded direct fine-scale evaluation of compounds on native surfaces. Here, we asked whether natural products from the red macroalga Callophycus serratus act in surface-mediated defense against pathogenic microbes. Bromophycolides and callophycoic acids from algal extracts inhibited growth of Lindra thalassiae, a marine fungal pathogen, and represent the largest group of algal antifungal chemical defenses reported to date. Desorption electrospray ionization mass spectrometry (DESI-MS) imaging revealed that surface-associated bromophycolides were found exclusively in association with distinct surface patches at concentrations sufficient for fungal inhibition; DESI-MS also indicated the presence of bromophycolides within internal algal tissue. This is among the first examples of natural product imaging on biological surfaces, suggesting the importance of secondary metabolites in localized ecological interactions, and illustrating the potential of DESI-MS in understanding chemically-mediated biological processes.
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Vaidyanathan S, Fletcher JS, Jarvis RM, Henderson A, Lockyer NP, Goodacre R, Vickerman JC. Explanatory multivariate analysis of ToF-SIMS spectra for the discrimination of bacterial isolates. Analyst 2009; 134:2352-60. [DOI: 10.1039/b907570d] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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42
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Esquenazi E, Yang YL, Watrous J, Gerwick WH, Dorrestein PC. Imaging mass spectrometry of natural products. Nat Prod Rep 2009; 26:1521-34. [DOI: 10.1039/b915674g] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
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