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Wendel-Garcia PD, Eberle B, Kleinert EM, Hilty MP, Blumenthal S, Spanaus K, Fodor P, Maggiorini M. Effects of enhanced adsorption haemofiltration versus haemoadsorption in severe, refractory septic shock with high levels of endotoxemia: the ENDoX bicentric, randomized, controlled trial. Ann Intensive Care 2023; 13:127. [PMID: 38095800 PMCID: PMC10721780 DOI: 10.1186/s13613-023-01224-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Accepted: 12/06/2023] [Indexed: 12/17/2023] Open
Abstract
BACKGROUND Endotoxin adsorption is a promising but controversial therapy in severe, refractory septic shock and conflicting results exist on the effective capacity of available devices to reduce circulating endotoxin and inflammatory cytokine levels. METHODS Multiarm, randomized, controlled trial in two Swiss intensive care units, with a 1:1:1 randomization of patients suffering severe, refractory septic shock with high levels of endotoxemia, defined as an endotoxin activity ≥ 0.6, a vasopressor dependency index ≥ 3, volume resuscitation of at least 30 ml/kg/24 h and at least single organ failure, to a haemoadsorption (Toraymyxin), an enhanced adsorption haemofiltration (oXiris) or a control intervention. Primary endpoint was the difference in endotoxin activity at 72-h post-intervention to baseline. In addition, inflammatory cytokine, vasopressor dependency index and SOFA-Score dynamics over the initial 72 h were assessed inter alia. RESULTS In the 30, out of 437 screened, randomized patients (10 Standard of care, 10 oXiris, 10 Toraymyxin), endotoxin reduction at 72-h post-intervention-start did not differ among interventions (Standard of Care: 12 [1-42]%, oXiris: 21 [10-51]%, Toraymyxin: 23 [10-36]%, p = 0.82). Furthermore, no difference between groups could be observed neither for reduction of inflammatory cytokine levels (p = 0.58), nor for vasopressor weaning (p = 0.95) or reversal of organ injury (p = 0.22). CONCLUSIONS In a highly endotoxemic, severe, refractory septic shock population neither the Toraymyxin adsorber nor the oXiris membrane could show a reduction in circulating endotoxin or cytokine levels over standard of care. Trial registration ClinicalTrials.gov. NCT01948778. Registered August 30, 2013. https://clinicaltrials.gov/study/NCT01948778.
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Affiliation(s)
- Pedro David Wendel-Garcia
- Institute of Intensive Care Medicine, University Hospital Zurich, Rämistrasse 100, 8091, Zurich, Switzerland.
| | - Barbara Eberle
- Institute of Intensive Care Medicine, University Hospital Zurich, Rämistrasse 100, 8091, Zurich, Switzerland
| | - Eva-Maria Kleinert
- Institute of Intensive Care Medicine, University Hospital Zurich, Rämistrasse 100, 8091, Zurich, Switzerland
| | - Matthias Peter Hilty
- Institute of Intensive Care Medicine, University Hospital Zurich, Rämistrasse 100, 8091, Zurich, Switzerland
| | | | - Katharina Spanaus
- Institute of Clinical Chemistry, University Hospital Zurich, Zurich, Switzerland
| | - Patricia Fodor
- Institute of Intensive Care Medicine, Triemli Hospital, Zurich, Switzerland
| | - Marco Maggiorini
- Institute of Intensive Care Medicine, University Hospital Zurich, Rämistrasse 100, 8091, Zurich, Switzerland
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2
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Mikhael A, Hardie D, Smith D, Pětrošová H, Ernst RK, Goodlett DR. Structural Elucidation of Intact Rough-type Lipopolysaccharides Using Field Asymmetric Ion Mobility Spectrometry and Kendrick Mass Defect Plots. Anal Chem 2023; 95:16796-16800. [PMID: 37943784 PMCID: PMC10666081 DOI: 10.1021/acs.analchem.3c02947] [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: 07/05/2023] [Accepted: 09/15/2023] [Indexed: 11/12/2023]
Abstract
Lipopolysaccharides (LPSs) are a hallmark virulence factor of Gram-negative bacteria. They are complex, structurally heterogeneous mixtures due to variations in number, type, and position of their simplest units: fatty acids and monosaccharides. Thus, LPS structural characterization by traditional mass spectrometry (MS) methods is challenging. Here, we describe the benefits of field asymmetric ion mobility spectrometry (FAIMS) for analysis of an intact R-type lipopolysaccharide complex mixture (lipooligosaccharide; LOS). Structural characterization was performed using Escherichia coli J5 (Rc mutant) LOS, a TLR4 agonist widely used in glycoconjugate vaccine research. FAIMS gas-phase fractionation improved the (S/N) ratio and number of detected LOS species. Additionally, FAIMS allowed the separation of overlapping isobars facilitating their tandem MS characterization and unequivocal structural assignments. In addition to FAIMS gas-phase fractionation benefits, extra sorting of the structurally related LOS molecules was further accomplished using Kendrick mass defect (KMD) plots. Notably, a custom KMD base unit of [Na-H] created a highly organized KMD plot that allowed identification of interesting and novel structural differences across the different LOS ion families, i.e., ions with different acylation degrees, oligosaccharides composition, and chemical modifications. Defining the composition of a single LOS ion by tandem MS along with the organized KMD plot structural network was sufficient to deduce the composition of 181 LOS species out of 321 species present in the mixture. The combination of FAIMS and KMD plots allowed in-depth characterization of the complex LOS mixture and uncovered a wealth of novel information about its structural variations.
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Affiliation(s)
- Abanoub Mikhael
- Department
of Biochemistry and Microbiology, University
of Victoria, Victoria, British Columbia V8W 2Y2, Canada
- University
of Victoria Genome British Columbia Proteomics Centre, Victoria, British Columbia V8Z 7X8, Canada
| | - Darryl Hardie
- University
of Victoria Genome British Columbia Proteomics Centre, Victoria, British Columbia V8Z 7X8, Canada
| | - Derek Smith
- University
of Victoria Genome British Columbia Proteomics Centre, Victoria, British Columbia V8Z 7X8, Canada
| | - Helena Pětrošová
- Department
of Biochemistry and Microbiology, University
of Victoria, Victoria, British Columbia V8W 2Y2, Canada
- University
of Victoria Genome British Columbia Proteomics Centre, Victoria, British Columbia V8Z 7X8, Canada
| | - Robert K. Ernst
- Department
of Microbial Pathogenesis, University of
Maryland—Baltimore, Baltimore, Maryland 21201, United States
| | - David R. Goodlett
- Department
of Biochemistry and Microbiology, University
of Victoria, Victoria, British Columbia V8W 2Y2, Canada
- University
of Victoria Genome British Columbia Proteomics Centre, Victoria, British Columbia V8Z 7X8, Canada
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3
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Mikhael A, Hardie D, Smith D, Pětrošová H, Ernst RK, Goodlett DR. Structural Elucidation of Intact Rough-Type Lipopolysaccharides using Field Asymmetric Ion Mobility Spectrometry and Kendrick Mass Defect Plots. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.06.21.545950. [PMID: 37461651 PMCID: PMC10349945 DOI: 10.1101/2023.06.21.545950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 07/24/2023]
Abstract
Lipopolysaccharide (LPS) is a hallmark virulence factor of Gram-negative bacteria. It is a complex, structurally heterogeneous mixture due to variations in number, type, and position of its simplest units: fatty acids and monosaccharides. Thus, LPS structural characterization by traditional mass spectrometry (MS) methods is challenging. Here, we describe the benefits of field asymmetric ion mobility spectrometry (FAIMS) for analysis of intact R-type lipopolysaccharide complex mixture (lipooligosaccharide; LOS). Structural characterization was performed using Escherichia coli J5 (Rc mutant) LOS, a TLR4 agonist widely used in glycoconjugate vaccine research. FAIMS gas phase fractionation improved the (S/N) ratio and number of detected LOS species. Additionally, FAIMS allowed the separation of overlapping isobars facilitating their tandem MS characterization and unequivocal structural assignments. In addition to FAIMS gas phase fractionation benefits, extra sorting of the structurally related LOS molecules was further accomplished using Kendrick mass defect (KMD) plots. Notably, a custom KMD base unit of [NaH] created a highly organized KMD plot that allowed identification of interesting and novel structural differences across the different LOS ion families; i.e., ions with different acylation degrees, oligosaccharides composition, and chemical modifications. Defining the composition of a single LOS ion by tandem MS along with the organized KMD plot structural network was sufficient to deduce the composition of 179 LOS species out of 321 species present in the mixture. The combination of FAIMS and KMD plots allowed in-depth characterization of the complex LOS mixture and uncovered a wealth of novel information about its structural variations.
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Affiliation(s)
- Abanoub Mikhael
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
- University of Victoria Genome British Columbia Proteomics Centre, Victoria, British Columbia V8Z 7X8, Canada
| | - Darryl Hardie
- University of Victoria Genome British Columbia Proteomics Centre, Victoria, British Columbia V8Z 7X8, Canada
| | - Derek Smith
- University of Victoria Genome British Columbia Proteomics Centre, Victoria, British Columbia V8Z 7X8, Canada
| | - Helena Pětrošová
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
- University of Victoria Genome British Columbia Proteomics Centre, Victoria, British Columbia V8Z 7X8, Canada
| | - Robert K Ernst
- Department of Microbial Pathogenesis, University of Maryland - Baltimore, Baltimore, MD, 21201 USA
| | - David R Goodlett
- Department of Biochemistry and Microbiology, University of Victoria, Victoria, British Columbia V8W 2Y2, Canada
- University of Victoria Genome British Columbia Proteomics Centre, Victoria, British Columbia V8Z 7X8, Canada
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4
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Wang XY, Liu WG, Hou AS, Song YX, Ma YL, Wu XD, Cao JB, Mi WD. Dysfunction of EAAT3 Aggravates LPS-Induced Post-Operative Cognitive Dysfunction. MEMBRANES 2022; 12:membranes12030317. [PMID: 35323793 PMCID: PMC8951453 DOI: 10.3390/membranes12030317] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/16/2022] [Revised: 03/04/2022] [Accepted: 03/07/2022] [Indexed: 11/23/2022]
Abstract
Numerous results have revealed an association between inhibited function of excitatory amino acid transporter 3 (EAAT3) and several neurodegenerative diseases. This was also corroborated by our previous studies which showed that the EAAT3 function was intimately linked to learning and memory. With this premise, we examined the role of EAAT3 in post-operative cognitive dysfunction (POCD) and explored the potential benefit of riluzole in countering POCD in the present study. We first established a recombinant adeno-associated-viral (rAAV)-mediated shRNA to knockdown SLC1A1/EAAT3 expression in the hippocampus of adult male mice. The mice then received an intracerebroventricular microinjection of 2 μg lipopolysaccharide (LPS) to construct the POCD model. In addition, for old male mice, 4 mg/kg of riluzole was intraperitoneally injected for three consecutive days, with the last injection administered 2 h before the LPS microinjection. Cognitive function was assessed using the Morris water maze 24 h following the LPS microinjection. Animal behavioral tests, as well as pathological and biochemical assays, were performed to clarify the role of EAAT3 function in POCD and evaluate the effect of activating the EAAT3 function by riluzole. In the present study, we established a mouse model with hippocampal SLC1A1/EAAT3 knockdown and found that hippocampal SLC1A1/EAAT3 knockdown aggravated LPS-induced learning and memory deficits in adult male mice. Meanwhile, LPS significantly inhibited the expression of EAAT3 membrane protein and the phosphorylation level of GluA1 protein in the hippocampus of adult male mice. Moreover, riluzole pretreatment significantly increased the expression of hippocampal EAAT3 membrane protein and also ameliorated LPS-induced cognitive impairment in elderly male mice. Taken together, our results demonstrated that the dysfunction of EAAT3 is an important risk factor for POCD susceptibility and therefore, it may become a promising target for POCD treatment.
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Affiliation(s)
- Xiao-Yan Wang
- Chinese PLA Medical School, Beijing 100853, China; (X.-Y.W.); (W.-G.L.)
- Department of Anesthesiology, The Fourth Medical Center of Chinese PLA General Hospital, Beijing 100037, China
| | - Wen-Gang Liu
- Chinese PLA Medical School, Beijing 100853, China; (X.-Y.W.); (W.-G.L.)
- Department of Anesthesiology, The First Medical Center of Chinese PLA General Hospital, Beijing 100853, China; (A.-S.H.); (Y.-X.S.); (Y.-L.M.); (X.-D.W.)
| | - Ai-Sheng Hou
- Department of Anesthesiology, The First Medical Center of Chinese PLA General Hospital, Beijing 100853, China; (A.-S.H.); (Y.-X.S.); (Y.-L.M.); (X.-D.W.)
| | - Yu-Xiang Song
- Department of Anesthesiology, The First Medical Center of Chinese PLA General Hospital, Beijing 100853, China; (A.-S.H.); (Y.-X.S.); (Y.-L.M.); (X.-D.W.)
| | - Yu-Long Ma
- Department of Anesthesiology, The First Medical Center of Chinese PLA General Hospital, Beijing 100853, China; (A.-S.H.); (Y.-X.S.); (Y.-L.M.); (X.-D.W.)
| | - Xiao-Dong Wu
- Department of Anesthesiology, The First Medical Center of Chinese PLA General Hospital, Beijing 100853, China; (A.-S.H.); (Y.-X.S.); (Y.-L.M.); (X.-D.W.)
| | - Jiang-Bei Cao
- Department of Anesthesiology, The First Medical Center of Chinese PLA General Hospital, Beijing 100853, China; (A.-S.H.); (Y.-X.S.); (Y.-L.M.); (X.-D.W.)
- Correspondence: (J.-B.C.); (W.-D.M.)
| | - Wei-Dong Mi
- Department of Anesthesiology, The First Medical Center of Chinese PLA General Hospital, Beijing 100853, China; (A.-S.H.); (Y.-X.S.); (Y.-L.M.); (X.-D.W.)
- Correspondence: (J.-B.C.); (W.-D.M.)
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5
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Zaikin VG, Borisov RS. Mass Spectrometry as a Crucial Analytical Basis for Omics Sciences. JOURNAL OF ANALYTICAL CHEMISTRY 2021. [PMCID: PMC8693159 DOI: 10.1134/s1061934821140094] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
This review is devoted to the consideration of mass spectrometric platforms as applied to omics sciences. The most significant attention is paid to omics related to life sciences (genomics, proteomics, meta-bolomics, lipidomics, glycomics, plantomics, etc.). Mass spectrometric approaches to solving the problems of petroleomics, polymeromics, foodomics, humeomics, and exosomics, related to inorganic sciences, are also discussed. The review comparatively presents the advantages of various principles of separation and mass spectral techniques, complementary derivatization, used to obtain large arrays of various structural and quantitative information in the mentioned omics sciences.
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Affiliation(s)
- V. G. Zaikin
- Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 119991 Moscow, Russia
| | - R. S. Borisov
- Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 119991 Moscow, Russia
- RUDN University, 117198 Moscow, Russia
- Core Facility Center “Arktika,” Northern (Arctic) Federal University, 163002 Arkhangelsk, Russia
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6
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Di Lorenzo F, Duda KA, Lanzetta R, Silipo A, De Castro C, Molinaro A. A Journey from Structure to Function of Bacterial Lipopolysaccharides. Chem Rev 2021; 122:15767-15821. [PMID: 34286971 DOI: 10.1021/acs.chemrev.0c01321] [Citation(s) in RCA: 72] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Lipopolysaccharide (LPS) is a crucial constituent of the outer membrane of most Gram-negative bacteria, playing a fundamental role in the protection of bacteria from environmental stress factors, in drug resistance, in pathogenesis, and in symbiosis. During the last decades, LPS has been thoroughly dissected, and massive information on this fascinating biomolecule is now available. In this Review, we will give the reader a third millennium update of the current knowledge of LPS with key information on the inherent peculiar carbohydrate chemistry due to often puzzling sugar residues that are uniquely found on it. Then, we will drive the reader through the complex and multifarious immunological outcomes that any given LPS can raise, which is strictly dependent on its chemical structure. Further, we will argue about issues that still remain unresolved and that would represent the immediate future of LPS research. It is critical to address these points to complete our notions on LPS chemistry, functions, and roles, in turn leading to innovative ways to manipulate the processes involving such a still controversial and intriguing biomolecule.
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Affiliation(s)
- Flaviana Di Lorenzo
- Department of Chemical Sciences, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.,Task Force on Microbiome Studies, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy
| | - Katarzyna A Duda
- Research Center Borstel Leibniz Lung Center, Parkallee 4a, 23845 Borstel, Germany
| | - Rosa Lanzetta
- Department of Chemical Sciences, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy
| | - Alba Silipo
- Department of Chemical Sciences, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.,Task Force on Microbiome Studies, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy
| | - Cristina De Castro
- Task Force on Microbiome Studies, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.,Department of Agricultural Sciences, University of Naples Federico II, Via Università 96, 80055 Portici, Naples, Italy
| | - Antonio Molinaro
- Department of Chemical Sciences, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.,Task Force on Microbiome Studies, University of Naples Federico II, Via Cinthia 4, 80126 Naples, Italy.,Department of Chemistry, School of Science, Osaka University, 1-1 Osaka University Machikaneyama, Toyonaka, Osaka 560-0043, Japan
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7
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Luong P, Dube DH. Dismantling the bacterial glycocalyx: Chemical tools to probe, perturb, and image bacterial glycans. Bioorg Med Chem 2021; 42:116268. [PMID: 34130219 DOI: 10.1016/j.bmc.2021.116268] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2021] [Revised: 05/27/2021] [Accepted: 06/01/2021] [Indexed: 12/20/2022]
Abstract
The bacterial glycocalyx is a quintessential drug target comprised of structurally distinct glycans. Bacterial glycans bear unusual monosaccharide building blocks whose proper construction is critical for bacterial fitness, survival, and colonization in the human host. Despite their appeal as therapeutic targets, bacterial glycans are difficult to study due to the presence of rare bacterial monosaccharides that are linked and modified in atypical manners. Their structural complexity ultimately hampers their analytical characterization. This review highlights recent advances in bacterial chemical glycobiology and focuses on the development of chemical tools to probe, perturb, and image bacterial glycans and their biosynthesis. Current technologies have enabled the study of bacterial glycosylation machinery even in the absence of detailed structural information.
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Affiliation(s)
- Phuong Luong
- Department of Chemistry & Biochemistry, Bowdoin College, 6600 College Station, Brunswick, ME 04011, USA
| | - Danielle H Dube
- Department of Chemistry & Biochemistry, Bowdoin College, 6600 College Station, Brunswick, ME 04011, USA.
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8
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Buré C, Le Sénéchal C, Macias L, Tokarski C, Vilain S, Brodbelt JS. Characterization of Isomers of Lipid A from Pseudomonas aeruginosa PAO1 by Liquid Chromatography with Tandem Mass Spectrometry with Higher-Energy Collisional Dissociation and Ultraviolet Photodissociation. Anal Chem 2021; 93:4255-4262. [PMID: 33625828 PMCID: PMC8377747 DOI: 10.1021/acs.analchem.0c05069] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Lipopolysaccharides (LPS) constitute the outermost layer of Gram-negative bacteria and consequently play an important role in bacterial infections. In order to address public health issues posed by Gram-negative bacteria, it is necessary to elucidate the structure of the molecular actors at the forefront of infections. LPS virulence and toxicity are partially modulated by lipid A, a hydrophobic saccharolipid that anchors LPS to the bacterial outer membrane. Understanding the lipid A structure is inherently intertwined with understanding its role as an endotoxin. Accordingly, several successful strategies incorporating tandem mass spectrometry have been applied toward the structural analysis of lipid A. Herein, a shotgun HCD strategy was applied toward the characterization of the lipid A profile of Pseudomonas aeruginosa PAO1. This analysis was enhanced by the development of an LC-MS/MS approach to eliminate isomeric signals in the MS/MS spectra that confounded characterization. Importantly, combining reverse phase chromatography with HCD and ultraviolet photodissociation analyses of the lipid A profile revealed the presence of previously unreported lipid A acyl chain positional isomers. Altogether, these strategies provide the most in-depth structural and molecular characterization of PAO1 lipid A to date.
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Affiliation(s)
- Corinne Buré
- Institute of Chemistry & Biology of Membranes & Nanoobjects, UMR 5248, CNRS, University of Bordeaux, Bordeaux INP, Bordeaux, Pessac F-33076, France
- Department of Chemistry, University of Texas, Austin, Texas 78712, United States
| | - Caroline Le Sénéchal
- Institute of Chemistry & Biology of Membranes & Nanoobjects, UMR 5248, CNRS, University of Bordeaux, Bordeaux INP, Bordeaux, Pessac F-33076, France
| | - Luis Macias
- Department of Chemistry, University of Texas, Austin, Texas 78712, United States
| | - Caroline Tokarski
- Institute of Chemistry & Biology of Membranes & Nanoobjects, UMR 5248, CNRS, University of Bordeaux, Bordeaux INP, Bordeaux, Pessac F-33076, France
| | - Sébastien Vilain
- Institute of Chemistry & Biology of Membranes & Nanoobjects, UMR 5248, CNRS, University of Bordeaux, Bordeaux INP, Bordeaux, Pessac F-33076, France
| | - Jennifer S Brodbelt
- Department of Chemistry, University of Texas, Austin, Texas 78712, United States
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Chang DPS, Guan XL. Metabolic Versatility of Mycobacterium tuberculosis during Infection and Dormancy. Metabolites 2021; 11:88. [PMID: 33540752 PMCID: PMC7913082 DOI: 10.3390/metabo11020088] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2020] [Revised: 01/16/2021] [Accepted: 01/29/2021] [Indexed: 12/18/2022] Open
Abstract
Mycobacterium tuberculosis (Mtb), the causative agent of tuberculosis (TB), is a highly successful intracellular pathogen with the ability to withstand harsh conditions and reside long-term within its host. In the dormant and persistent states, the bacterium tunes its metabolism and is able to resist the actions of antibiotics. One of the main strategies Mtb adopts is through its metabolic versatility-it is able to cometabolize a variety of essential nutrients and direct these nutrients simultaneously to multiple metabolic pathways to facilitate the infection of the host. Mtb further undergo extensive remodeling of its metabolic pathways in response to stress and dormancy. In recent years, advancement in systems biology and its applications have contributed substantially to a more coherent view on the intricate metabolic networks of Mtb. With a more refined appreciation of the roles of metabolism in mycobacterial infection and drug resistance, and the success of drugs targeting metabolism, there is growing interest in further development of anti-TB therapies that target metabolism, including lipid metabolism and oxidative phosphorylation. Here, we will review current knowledge revolving around the versatility of Mtb in remodeling its metabolism during infection and dormancy, with a focus on central carbon metabolism and lipid metabolism.
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Affiliation(s)
| | - Xue Li Guan
- Lee Kong Chian School of Medicine, Nanyang Technological University, 59 Nanyang Drive, Singapore 636921, Singapore;
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10
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Bucsella B, Hoffmann A, Zollinger M, Stephan F, Pattky M, Daumke R, Heiligtag FJ, Frank B, Bassas-Galia M, Zinn M, Kalman F. Novel RP-HPLC based assay for selective and sensitive endotoxin quantification. ANALYTICAL METHODS : ADVANCING METHODS AND APPLICATIONS 2020; 12:4621-4634. [PMID: 32924034 DOI: 10.1039/d0ay00872a] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The paper presents a novel instrumental analytical endotoxin quantification assay. It uses common analytical laboratory equipment (HPLC-FLD) and allows quantifying endotoxins (ETs) in different matrices from about 109 EU per mL down to about 40 EU per mL (RSE based). Test results are obtained in concentration units (e.g. ng ET per mL), which can then be converted to commonly used endotoxin units (EU per mL) in case of known pyrogenic activity. During endotoxin hydrolysis, the endotoxin specific rare sugar acid KDO is obtained quantitatively. After that, KDO is stoichiometrically reacted with DMB, which results in a highly fluorescent derivative. The mixture is separated using RP-HPLC followed by KDO-DMB quantification with a fluorescence detector. Based on the KDO content, the endotoxin content in the sample is calculated. The developed assay is economic and has a small error. Its applicability was demonstrated in applied research. ETs were quantified in purified bacterial biopolymers, which were produced by Gram-negative bacteria. Results were compared to LAL results obtained for the same samples. A high correlation was found between the results of both methods. Further, the new assay was utilized with high success during the development of novel endotoxin specific depth filters, which allow efficient, economic and sustainable ET removal during DSP. Those examples demonstrate that the new assay has the potential to complement the animal-based biological LAL pyrogenic quantification tests, which are accepted today by the major health authorities worldwide for the release of commercial pharmaceutical products.
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Affiliation(s)
- Blanka Bucsella
- University of Zürich, Department of Chemistry, Winterthurerstr. 190, Zürich, CH-8057, Switzerland and HES-SO Valais (University of Applied Sciences, Sion; Wallis), Institute of Life Technologies, Route du Rawyl 64, CH-1950 Sion 2, Switzerland.
| | - Anika Hoffmann
- HES-SO Valais (University of Applied Sciences, Sion; Wallis), Institute of Life Technologies, Route du Rawyl 64, CH-1950 Sion 2, Switzerland.
| | - Mathieu Zollinger
- HES-SO Valais (University of Applied Sciences, Sion; Wallis), Institute of Life Technologies, Route du Rawyl 64, CH-1950 Sion 2, Switzerland.
| | - Fabio Stephan
- HES-SO Valais (University of Applied Sciences, Sion; Wallis), Institute of Life Technologies, Route du Rawyl 64, CH-1950 Sion 2, Switzerland. and Lonza AG, Quality Control Biopharma, Rottenstrasse 6, CH-3930 Visp, Switzerland
| | - Martin Pattky
- HES-SO Valais (University of Applied Sciences, Sion; Wallis), Institute of Life Technologies, Route du Rawyl 64, CH-1950 Sion 2, Switzerland. and Lonza AG, Quality Control Biopharma, Rottenstrasse 6, CH-3930 Visp, Switzerland
| | - Ralph Daumke
- FILTROX AG, Moosmühlestr. 6, CH-9001 St. Gallen, Switzerland
| | | | - Brian Frank
- FILTROX AG, Moosmühlestr. 6, CH-9001 St. Gallen, Switzerland
| | - Mònica Bassas-Galia
- HES-SO Valais (University of Applied Sciences, Sion; Wallis), Institute of Life Technologies, Route du Rawyl 64, CH-1950 Sion 2, Switzerland. and FILTROX AG, Moosmühlestr. 6, CH-9001 St. Gallen, Switzerland and Acrostak AG, Stegackerstrasse 14, 8409 Winterthur, Switzerland
| | - Manfred Zinn
- HES-SO Valais (University of Applied Sciences, Sion; Wallis), Institute of Life Technologies, Route du Rawyl 64, CH-1950 Sion 2, Switzerland.
| | - Franka Kalman
- HES-SO Valais (University of Applied Sciences, Sion; Wallis), Institute of Life Technologies, Route du Rawyl 64, CH-1950 Sion 2, Switzerland. and Acrostak AG, Stegackerstrasse 14, 8409 Winterthur, Switzerland
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11
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Oyewole OA, Mitchell J, Thresh S, Zinkevich V. The purification and functional study of new compounds produced by Escherichia coli that influence the growth of sulfate reducing bacteria. ACTA ACUST UNITED AC 2020. [DOI: 10.1080/2314808x.2020.1752033] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Affiliation(s)
| | - Julian Mitchell
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, UK
| | - Sarah Thresh
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, UK
| | - Vitaly Zinkevich
- School of Pharmacy and Biomedical Sciences, University of Portsmouth, Portsmouth, UK
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12
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Klein DR, Powers MJ, Trent MS, Brodbelt JS. Top-Down Characterization of Lipooligosaccharides from Antibiotic-Resistant Bacteria. Anal Chem 2019; 91:9608-9615. [PMID: 31305072 PMCID: PMC6702669 DOI: 10.1021/acs.analchem.9b00940] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Modification of structures of lipooligosaccharides (LOS) represents one prevalent mechanism by which Gram-negative bacteria can become resistant to key antibiotics. Owing to the significant complexity of LOS, the structural characterization of these amphipathic lipids has largely focused on elucidation of the lipid A substructures. Analysis of intact LOS enables detection of core oligosaccharide modifications and gives insight into the heterogeneity that results from combinations of lipid A and oligosaccharide substructures. Top-down analysis of intact LOS also provides the opportunity to determine unknown oligosaccharide structures, which is particularly advantageous in the context of glycoconjugate vaccine development. Advances in mass spectrometry technologies, including the development of MSn capabilities and alternative ion activation techniques, have made top-down analysis an indispensable tool for structural characterization of complex biomolecules. Here we combine online chromatographic separations with MS3 utilizing ultraviolet photodissociation (UVPD) and higher-energy collisional dissociation (HCD). HCD generally provides information about the presence of labile modifications via neutral loss fragments in addition to the saccharide linkage arrangement, whereas UVPD gives more detailed insight about saccharide branching and the positions of nonstoichiometric modifications. This integrated approach was used to characterize LOS from Acinetobacter baumannii 1205 and 5075. Notably, MS3 analysis of A. baumannii 1205, an antibiotic-resistant strain, confirmed phosphoethanolamine and hexosamine modification of the lipid A substructure and further enabled derivation of a core oligosaccharide structure.
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Affiliation(s)
- Dustin R. Klein
- Department of Chemistry, The University of Texas at Austin, Austin, TX 78712
| | - Matthew J. Powers
- Department of Infectious Diseases, The University of Georgia, College of Veterinary Medicine, Athens, GA 30602
- Department of Microbiology, The University of Georgia, College of Arts and Sciences, Athens, GA 30602
| | - M. Stephen Trent
- Department of Infectious Diseases, The University of Georgia, College of Veterinary Medicine, Athens, GA 30602
- Department of Microbiology, The University of Georgia, College of Arts and Sciences, Athens, GA 30602
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13
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Crittenden CM, Escobar EE, Williams PE, Sanders JD, Brodbelt JS. Characterization of Antigenic Oligosaccharides from Gram-Negative Bacteria via Activated Electron Photodetachment Mass Spectrometry. Anal Chem 2019; 91:4672-4679. [PMID: 30844257 DOI: 10.1021/acs.analchem.9b00048] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Lipooligosaccharides (LOS), composed of hydrophilic oligosaccharides and hydrophobic lipid A domains, are found on the outer membranes of Gram-negative bacteria. Here we report the characterization of deacylated LOS of LPS by activated-electron photodetachment mass spectrometry. Collision induced dissociation (CID) of these phosphorylated oligosaccharides produces simple MS/MS spectra with most fragment ions arising from cleavages near the reducing end of the molecule where the phosphate groups are located. In contrast, 193 nm ultraviolet photodissociation (UVPD) generates a wide array of product ions throughout the oligosaccharide including cross-ring fragments that illuminate the branching patterns. However, there are also product ions that are redundant or uninformative, resulting in more congested spectra that complicate interpretation. In this work, a hybrid UVPD-CID approach known as activated-electron photodetachment (a-EPD) affords less congested spectra than UVPD alone and richer fragmentation patterns than CID alone. a-EPD combines UVPD of negatively charged oligosaccharides to yield abundant charge-reduced radical ions which are subsequently interrogated by collisional activation. CID of the charge-reduced precursors results in extensive fragmentation throughout the backbone of the oligosaccharide. This hybridized a-EPD approach was employed to characterize the structure and branching pattern of deacylated LOS of E. coli.
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Affiliation(s)
| | - Edwin E Escobar
- Department of Chemistry , University of Texas at Austin , Austin , Texas 78712 , United States
| | - Peggy E Williams
- Department of Chemistry , University of Texas at Austin , Austin , Texas 78712 , United States
| | - James D Sanders
- Department of Chemistry , University of Texas at Austin , Austin , Texas 78712 , United States
| | - Jennifer S Brodbelt
- Department of Chemistry , University of Texas at Austin , Austin , Texas 78712 , United States
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14
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Structures of O-specific polysaccharides of Pseudomonas psyhrotolerans BIM B-1158G. Carbohydr Res 2018; 465:35-39. [DOI: 10.1016/j.carres.2018.06.006] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Revised: 06/05/2018] [Accepted: 06/10/2018] [Indexed: 12/21/2022]
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15
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Crittenden CM, Herrera CM, Williams PE, Ricci DP, Swem LR, Trent MS, Brodbelt JS. Mapping phosphate modifications of substituted lipid A via a targeted MS 3 CID/UVPD strategy. Analyst 2018; 143:3091-3099. [PMID: 29881855 PMCID: PMC6019210 DOI: 10.1039/c8an00561c] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Structural characterization of lipid A from Gram-negative bacteria remains a significant challenge, especially with respect to localizing modifications of the phosphate groups typically found on the reducing and non-reducing ends of the β-1',6-linked glucosamine disaccharide backbone of lipid A. As reported here, combining traditional collisional activated dissociation (CAD) and ultraviolet photodissociation (UVPD) in a hybrid MS3 approach facilitates identification and localization of substituents of the phosphate groups. The focus is on rapid identification and characterization of substituted lipid A species with specific emphasis on the modifications on the 1 and 4' phosphate moieties. Mapping these modifications, typically ones that modify the surface charges of lipopolysaccharides, is particularly important owing to the impact of these types of modifications on antibiotic resistance. The presence of phosphoethanolamine, aminoarabinose, and galactosamine moieties in hexaacylated and heptaacylated lipid A species, including ones from Enterobacter cloacae and Acinetobacter baumannii, are characterized using a targeted MS3 strategy to identify glycosidic product ions (1,5X1 and 0,4A2, typically) which allow localization of the substituents.
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16
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Almostafa M, Fridgen TD, Banoub JH. Structural investigation by tandem mass spectrometry analysis of a heterogeneous mixture of Lipid A n isolated from the lipopolysaccharide of Aeromonas hydrophila SJ-55Ra. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2018; 32:167-183. [PMID: 29065225 DOI: 10.1002/rcm.8017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/15/2017] [Revised: 09/15/2017] [Accepted: 10/03/2017] [Indexed: 06/07/2023]
Abstract
RATIONALE We report herein the electrospray ionization mass spectrometry (ESI-MS) negative ion mode and low-energy collision-induced dissociation tandem mass spectrometry (CID-MS/MS) analysis of a mixture of lipid An isolated from the lipopolysaccharide (LPS) of a rough-resistant wild strain of the Gram-negative bacteria Aeromonas hydrophila grown in the presence of phages (SJ-55Ra). This investigation indicates that the presence of a mixture of lipid A acylated disaccharides, whose molecular structures were not relatively conserved, resulted from the incomplete LPS biosynthesis caused by the phage treatment. METHODS The heterogeneous lipid An mixture from the LPS-SJ55Ra was obtained following growth of the Gram-negative bacteria Aeromonas hydrophila (SJ-55R) in the presence of phages and isolation by the aqueous phenol method. Following hydrolysis and purification of the lipopolysaccharide, ESI-MS and low-energy CID-MS/MS analyses were performed on a triple-quadrupole (QqQ) and a Fourier transform ion cyclotron resonance (FTICR) instrument. RESULTS ESI-MS analysis suggested that this lipid An mixture contained eight molecular disaccharide anions and three monosaccharide anions. This series of lipid An was asymmetrically substituted with ((R)-14:0(3-OH)) fatty acids located at O-3 and N-2 and with branched fatty acids: (Cl4:0(3-(R)-O-C14:0)) and (C12:0(3-(R)-O-(14:0)) at the O-3' and N-2' positions. CONCLUSIONS Tandem mass spectrometric analyses allowed the exact determination of the fatty acid acylation locations on the D-GlcpN disaccharide. The MS/MS results established that it was possible to selectively cleave C-O, C-N, and C-C bonds, together with glycosidic C-O and cross-ring cleavages, affording excellent structural analysis of lipid A biomolecules.
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Affiliation(s)
- Mervt Almostafa
- Chemistry Department, Memorial University of Newfoundland, St. John's, Canada
| | - Travis D Fridgen
- Chemistry Department, Memorial University of Newfoundland, St. John's, Canada
| | - Joseph H Banoub
- Chemistry Department, Memorial University of Newfoundland, St. John's, Canada
- Special Projects, Science Branch, Department of Fisheries and Oceans Canada, St. John's, Canada
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Andersson J, Fuller MA, Wood K, Holt SA, Köper I. A tethered bilayer lipid membrane that mimics microbial membranes. Phys Chem Chem Phys 2018; 20:12958-12969. [DOI: 10.1039/c8cp01346b] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
This work presents a self-assembled lipid bilayer architecture mimicking the outer membrane of Gram negative bacteria.
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Affiliation(s)
- Jakob Andersson
- Flinders Centre for Nanoscale Science and Technology and College of Science and Engineering
- Flinders University
- Adelaide
- Australia
| | - Melanie A. Fuller
- Flinders Centre for Nanoscale Science and Technology and College of Science and Engineering
- Flinders University
- Adelaide
- Australia
| | - Kathleen Wood
- Australian Centre for Neutron Scattering
- Australian Nuclear Science and Technology Organisation
- Kirrawee DC
- Australia
| | - Stephen A. Holt
- Australian Centre for Neutron Scattering
- Australian Nuclear Science and Technology Organisation
- Kirrawee DC
- Australia
| | - Ingo Köper
- Flinders Centre for Nanoscale Science and Technology and College of Science and Engineering
- Flinders University
- Adelaide
- Australia
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18
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Russo G, Witos J, Rantamäki AH, Wiedmer SK. Cholesterol affects the interaction between an ionic liquid and phospholipid vesicles. A study by differential scanning calorimetry and nanoplasmonic sensing. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2017; 1859:2361-2372. [PMID: 28912102 DOI: 10.1016/j.bbamem.2017.09.011] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2017] [Revised: 09/01/2017] [Accepted: 09/10/2017] [Indexed: 10/18/2022]
Abstract
The present work aims at studying the interactions between cholesterol-rich phosphatidylcholine-based lipid vesicles and trioctylmethylphosphonium acetate ([P8881][OAc]), a biomass dissolving ionic liquid (IL). The effect of cholesterol was assayed by using differential scanning calorimetry (DSC) and nanoplasmonic sensing (NPS) measurement techniques. Cholesterol-enriched dipalmitoyl-phosphatidylcholine vesicles were exposed to different concentrations of the IL, and the derived membrane perturbation was monitored by DSC. The calorimetric data could suggest that the binding and infiltration of the IL are delayed in the vesicles containing cholesterol. To clarify our findings, NPS was applied to quantitatively follow the resistance of 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine incorporating 0, 10, and 50mol% of cholesterol toward the IL exposure over time. The membrane perturbation induced by different concentrations of IL was found to be a concentration dependent process on cholesterol-free lipid vesicles. Moreover, our results showed that lipid depletion in cholesterol-enriched lipid vesicles is inversely proportional to the increasing amount of cholesterol in the vesicles. These findings support that cholesterol-rich lipid bilayers are less susceptible toward membrane disrupting agents as compared to membranes that do not incorporate any sterols. This probably occurs because cholesterol tightens the phospholipid acyl chain packing of the plasma membranes, increasing their resistance and reducing their permeability.
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Affiliation(s)
- Giacomo Russo
- Department of Chemistry, P. O. Box 55, FIN-00014, University of Helsinki, Helsinki, Finland.
| | - Joanna Witos
- Department of Chemistry, P. O. Box 55, FIN-00014, University of Helsinki, Helsinki, Finland.
| | - Antti H Rantamäki
- Department of Chemistry, P. O. Box 55, FIN-00014, University of Helsinki, Helsinki, Finland.
| | - Susanne K Wiedmer
- Department of Chemistry, P. O. Box 55, FIN-00014, University of Helsinki, Helsinki, Finland.
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Zhao WX, Zhang JH, Cao JB, Wang W, Wang DX, Zhang XY, Yu J, Zhang YY, Zhang YZ, Mi WD. Acetaminophen attenuates lipopolysaccharide-induced cognitive impairment through antioxidant activity. J Neuroinflammation 2017; 14:17. [PMID: 28109286 PMCID: PMC5251335 DOI: 10.1186/s12974-016-0781-6] [Citation(s) in RCA: 71] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2016] [Accepted: 12/16/2016] [Indexed: 12/20/2022] Open
Abstract
Background Considerable evidence has shown that neuroinflammation and oxidative stress play an important role in the pathophysiology of postoperative cognitive dysfunction (POCD) and other progressive neurodegenerative disorders. Increasing evidence suggests that acetaminophen (APAP) has unappreciated antioxidant and anti-inflammatory properties. However, the impact of APAP on the cognitive sequelae of inflammatory and oxidative stress is unknown. The objective of this study is to explore whether APAP could have neuroprotective effects on lipopolysaccharide (LPS)-induced cognitive impairment in mice. Methods A mouse model of LPS-induced cognitive impairment was established to evaluate the neuroprotective effects of APAP against LPS-induced cognitive impairment. Adult C57BL/6 mice were treated with APAP half an hour prior to intracerebroventricular microinjection of LPS and every day thereafter, until the end of the study period. The Morris water maze was used to assess cognitive function from postinjection days 1 to 3. Animal behavioural tests as well as pathological and biochemical assays were performed to evaluate LPS-induced hippocampal damage and the neuroprotective effect of APAP. Results Mice treated with LPS exhibited impaired performance in the Morris water maze without changing spontaneous locomotor activity, which was ameliorated by treatment with APAP. APAP suppressed the accumulation of pro-inflammatory cytokines and microglial activation induced by LPS in the hippocampus. In addition, APAP increased SOD activity, reduced MDA levels, modulated glycogen synthase kinase 3β (GSK3β) activity and elevated brain-derived neurotrophic factor (BDNF) expression in the hippocampus. Moreover, APAP significantly decreased the Bax/Bcl-2 ratio and neuron apoptosis in the hippocampus of LPS-treated mice. Conclusions Our results suggest that APAP may possess a neuroprotective effect against LPS-induced cognitive impairment and inflammatory and oxidative stress via mechanisms involving its antioxidant and anti-inflammatory properties, as well as its ability to inhibit the mitochondrial permeability transition (MPT) pore and the subsequent apoptotic pathway.
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Affiliation(s)
- Wei-Xing Zhao
- Anesthesia and Operation Center, Chinese PLA General Hospital, 28th Fuxing Road, Haidian District, Beijing, 100853, China
| | - Jun-Han Zhang
- The Second Affiliated Hospital of Xiangya School of Medicine, Central South University, Changsha, 410008, China
| | - Jiang-Bei Cao
- Anesthesia and Operation Center, Chinese PLA General Hospital, 28th Fuxing Road, Haidian District, Beijing, 100853, China
| | - Wei Wang
- Anesthesia and Operation Center, Chinese PLA General Hospital, 28th Fuxing Road, Haidian District, Beijing, 100853, China.,Department of Anesthesiology, The General Hospital of the PLA Rocket Force, Beijing, 100088, China
| | - Dong-Xin Wang
- Department of Anesthesiology and Surgical Intensive Care, Peking University First Hospital, Beijing, 100034, China
| | - Xiao-Ying Zhang
- Anesthesia and Operation Center, Chinese PLA General Hospital, 28th Fuxing Road, Haidian District, Beijing, 100853, China
| | - Jun Yu
- Anesthesia and Operation Center, Chinese PLA General Hospital, 28th Fuxing Road, Haidian District, Beijing, 100853, China
| | - Yong-Yi Zhang
- Anesthesia and Operation Center, Chinese PLA General Hospital, 28th Fuxing Road, Haidian District, Beijing, 100853, China
| | - You-Zhi Zhang
- Institute of Pharmacology and Toxicology, Beijing Key laboratory of Neuropsychopharmacology, 27th Taiping Road, Haidian District, Beijing, 100850, China
| | - Wei-Dong Mi
- Anesthesia and Operation Center, Chinese PLA General Hospital, 28th Fuxing Road, Haidian District, Beijing, 100853, China.
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20
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Garrett TA. Major roles for minor bacterial lipids identified by mass spectrometry. Biochim Biophys Acta Mol Cell Biol Lipids 2016; 1862:1319-1324. [PMID: 27760388 DOI: 10.1016/j.bbalip.2016.10.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2016] [Revised: 10/03/2016] [Accepted: 10/04/2016] [Indexed: 01/31/2023]
Abstract
Mass spectrometry of lipids, especially those isolated from bacteria, has ballooned over the past two decades, affirming in the process the complexity of the lipidome. With this has come the identification of new and interesting lipid structures. Here is an overview of several novel lipids, from both Gram-negative and Gram-positive bacteria with roles in health and disease, whose structural identification was facilitated using mass spectrometry. This article is part of a Special Issue entitled: Bacterial Lipids edited by Russell E. Bishop.
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Affiliation(s)
- Teresa A Garrett
- Department of Chemistry, Vassar College, 124 Raymond Avenue, Poughkeepsie, NY 12604, United States.
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Phillips NJ, John CM, Jarvis GA. Analysis of Bacterial Lipooligosaccharides by MALDI-TOF MS with Traveling Wave Ion Mobility. JOURNAL OF THE AMERICAN SOCIETY FOR MASS SPECTROMETRY 2016; 27:1263-1276. [PMID: 27056565 DOI: 10.1007/s13361-016-1383-3] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2015] [Revised: 03/11/2016] [Accepted: 03/12/2016] [Indexed: 06/05/2023]
Abstract
Lipooligosaccharides (LOS) are major microbial virulence factors displayed on the outer membrane of rough-type Gram-negative bacteria. These amphipathic glycolipids are comprised of two domains, a core oligosaccharide linked to a lipid A moiety. Isolated LOS samples are generally heterogeneous mixtures of glycoforms, with structural variability in both domains. Traditionally, the oligosaccharide and lipid A components of LOS have been analyzed separately following mild acid hydrolysis, although important acid-labile moieties can be cleaved. Recently, an improved method was introduced for analysis of intact LOS by MALDI-TOF MS using a thin layer matrix composed of 2,4,6-trihydroxyacetophenone (THAP) and nitrocellulose. In addition to molecular ions, the spectra show in-source "prompt" fragments arising from regiospecific cleavage between the lipid A and oligosaccharide domains. Here, we demonstrate the use of traveling wave ion mobility spectrometry (TWIMS) for IMS-MS and IMS-MS/MS analyses of intact LOS from Neisseria spp. ionized by MALDI. Using IMS, the singly charged prompt fragments for the oligosaccharide and lipid A domains of LOS were readily separated into resolved ion plumes, permitting the extraction of specific subspectra, which led to increased confidence in assigning compositions and improved detection of less abundant ions. Moreover, IMS separation of precursor ions prior to collision-induced dissociation (CID) generated time-aligned, clean MS/MS spectra devoid of fragments from interfering species. Incorporating IMS into the profiling of intact LOS by MALDI-TOF MS exploits the unique domain structure of the molecule and offers a new means of extracting more detailed information from the analysis. Graphical Abstract ᅟ.
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Affiliation(s)
- Nancy J Phillips
- Department of Pharmaceutical Chemistry, University of California, San Francisco, CA, 94143, USA
| | - Constance M John
- Center for Immunochemistry, Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA, 94121, USA
- Department of Laboratory Medicine, University of California, San Francisco, CA, 94143, USA
| | - Gary A Jarvis
- Center for Immunochemistry, Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA, 94121, USA.
- Department of Laboratory Medicine, University of California, San Francisco, CA, 94143, USA.
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22
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Almostafa M, Allehyane B, Egli S, Bottaro C, Fridgen TD, Banoub J. Tandem mass spectrometry determination of the putative structure of a heterogeneous mixture of Lipid As isolated from the lipopolysaccharide of the Gram-negative bacteria Aeromonas liquefaciens SJ-19a. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2016; 30:1043-1058. [PMID: 27003042 DOI: 10.1002/rcm.7540] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2015] [Revised: 02/03/2016] [Accepted: 02/12/2016] [Indexed: 06/05/2023]
Abstract
RATIONALE We report herein the electrospray ionization mass spectrometry (ESI-MS) and low-energy collision-induced dissociation tandem mass spectrometry analysis (CID-MS/MS) of a mixture of lipid As isolated from the rough lipopolysaccharide (LPS) of the mutant wild strain of the Gram-negative bacteria Aeromonas liquefaciens (SJ-19a, resistant) grown in the presence of phages. The interaction between the phages and the Gram-negative bacteria regulates host specificity and the heterogeneity of the lipid A component of the LPS. METHODS The heterogeneous mixture of lipid As was isolated by the aqueous phenol method from the LPS of the rough wild strain of Gram-negative bacteria Aeromonas liquefaciens (SJ-19a). Hydrolysis of the LPS was with 1% acetic acid, and purification was by chromatography using Sephadex G-50 and Sephadex G-15. ESI-MS and low-energy CID-MS/MS analyses were performed with a triple-quadrupole (QqQ) and a Fourier transform ion cyclotron resonance (FTICR) mass spectrometer. RESULTS Preliminary analysis of the lipid As mixture was conducted by ESI-MS in the negative ion mode and the spectrum obtained suggested that the lipid A SJ-19a was composed of a heterogeneous mixture of different lipid A molecules. CID-MS/MS experiments confirmed the identities of the various mono-phosphorylated β-D-GlcpN-(1→6)-α-D-GlcpN disaccharide entities. This lipid As mixture was asymmetrically substituted with fatty acids such as ((R)-14:0(3-OH)), (14:0(3-(R)-(O-12:0)) and (14:0(3-(R)-O-(14:0)) located on the O-3, O-3', N-2 and N-2' positions, respectively. CONCLUSIONS Low-energy collision-induced dissociation tandem mass spectrometry in-space (QqQ-MS/MS) and in-time (FTICR-MS/MS) allowed the exact determination of the fatty acid acylation positions on the H2 PO3 →4-O'-β-D-GlcpN-(1→6)-α-D-GlcpN disaccharide backbones of this heterogeneous mixture of lipid As , composed inter alia of seven different substituted lipid As , formed from the incomplete biosynthesis of their respective LPS.
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Affiliation(s)
- Mervt Almostafa
- Chemistry Department, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Bashaeer Allehyane
- Chemistry Department, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Stefana Egli
- Chemistry Department, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Christina Bottaro
- Chemistry Department, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Travis D Fridgen
- Chemistry Department, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
| | - Joseph Banoub
- Chemistry Department, Memorial University of Newfoundland, St. John's, Newfoundland, Canada
- Special Projects, Science Branch, Department of Fisheries and Oceans Canada, St. John's, Newfoundland, Canada
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Wang P, Cao J, Liu N, Ma L, Zhou X, Zhang H, Wang Y. Protective Effects of Edaravone in Adult Rats with Surgery and Lipopolysaccharide Administration-Induced Cognitive Function Impairment. PLoS One 2016; 11:e0153708. [PMID: 27116382 PMCID: PMC4846078 DOI: 10.1371/journal.pone.0153708] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2016] [Accepted: 04/03/2016] [Indexed: 11/19/2022] Open
Abstract
Postoperative cognitive dysfunction (POCD) is a clinical syndrome characterized by cognitive declines in patients after surgery. Previous studies have suggested that surgery contributed to such impairment. It has been proven that neuroinflammation may exacerbate surgery-induced cognitive impairment in aged rats. The free radical scavenger edaravone has high blood brain barrier permeability, and was demonstrated to effectively remove free radicals from the brain and alleviate the development of POCD in patients undergoing carotid endarterectomy, suggesting its potential role in preventing POCD. For this reason, this study was designed to determine whether edaravone is protective against POCD through its inhibitory effects on inflammatory cytokines and oxidative stress. First, Sprague Dawley adult male rats were administered 3 mg/kg edaravone intraperitoneally after undergoing a unilateral nephrectomy combined with lipopolysaccharide injection. Second, behavioral parameters related to cognitive function were recorded by fear conditioning and Morris Water Maze tests. Last, superoxide dismutase activities and malondialdehyde levels were measured in the hippocampi and prefrontal cortex on postoperative days 3 and 7, and microglial (Iba1) activation, p-Akt and p-mTOR protein expression, and synaptic function (synapsin 1) were also examined 3 and 7 days after surgery. Rats that underwent surgery plus lipopolysaccharide administration showed significant impairments in spatial and working memory, accompanied by significant reductions in hippocampal-dependent and independent fear responses. All impairments were attenuated by treatment with edaravone. Moreover, an abnormal decrease in superoxide dismutase activation, abnormal increase in malondialdehyde levels, significant increase in microglial reactivity, downregulation of p-Akt and p-mTOR protein expression, and a statistically significant decrease in synapsin-1 were observed in the hippocampi and prefrontal cortices of rats at different time points after surgery. All mentioned abnormal changes were totally or partially reversed by edaravone. To our knowledge, few reports have shown greater protective effects of edaravone on POCD induced by surgery plus lipopolysaccharide administration from its anti-oxidative stress and anti-inflammatory effects, as well as maintenance of Akt/mTOR signal pathway activation; these might be closely related to the therapeutic effects of edaravone. Our research demonstrates the potential use of edaravone in the treatment of POCD.
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Affiliation(s)
- Peiqi Wang
- Department of Anesthesiology and Operation Center, Chinese PLA, General Hospital, Beijing, China
| | - Jiangbei Cao
- Department of Anesthesiology and Operation Center, Chinese PLA, General Hospital, Beijing, China
| | - Na Liu
- Department of Anesthesiology and Operation Center, Chinese PLA, General Hospital, Beijing, China
- Department of Anesthesiology, Affiliated Hospital of Chengde Medical University, Chengde, China
| | - Li Ma
- Department of Anesthesiology and Operation Center, Chinese PLA, General Hospital, Beijing, China
- Department of Anesthesiology, Beijing Military General Hospital of the Chinese People’s Liberation Army, Beijing, China
| | - Xueyue Zhou
- Department of Anesthesiology and Operation Center, Chinese PLA, General Hospital, Beijing, China
| | - Hong Zhang
- Department of Anesthesiology and Operation Center, Chinese PLA, General Hospital, Beijing, China
- * E-mail: (HZ); (YW)
| | - Yongan Wang
- State Key Laboratory of Toxicology and Medical Countermeasures, Academy of Military Medical Sciences, Beijing, China
- * E-mail: (HZ); (YW)
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24
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Vinnitskiy DZ, Ustyuzhanina NE, Nifantiev NE. Natural bacterial and plant biomolecules bearing α-d-glucuronic acid residues. Russ Chem Bull 2016. [DOI: 10.1007/s11172-015-1010-7] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
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25
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Klein DR, Holden DD, Brodbelt JS. Shotgun Analysis of Rough-Type Lipopolysaccharides Using Ultraviolet Photodissociation Mass Spectrometry. Anal Chem 2016; 88:1044-51. [PMID: 26616388 PMCID: PMC4970217 DOI: 10.1021/acs.analchem.5b04218] [Citation(s) in RCA: 81] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Detailed structural characterization of intact rough-type lipopolysaccharides (R-LPS) was accomplished using a multi-stage mass spectrometry (MS(3)) strategy consisting of collision-induced dissociation (CID) followed by 193 ultraviolet photodissociation (UVPD) implemented on an Orbitrap Fusion mass spectrometer. Complex mixtures of R-LPS from either Escherichia coli or Salmonella enterica were directly infused into the mass spectrometer using static source nanoelectrospray ionization (nanoESI). An initial CID event performed on an R-LPS precursor produced spectra with abundant ions corresponding to the lipid A and core oligosaccharide (OS) substructures. Comparison of CID spectra of R-LPS ions with varying lipid A and core OS structures verifies that lipid A and core OS ions are consistently produced in high abundance. The resulting lipid A and core OS ions were subsequently activated by CID, high-energy collision-induced dissociation (HCD), or UVPD. For both the lipid A and core OS substructures, HCD and UVPD produced highly informative complementary spectra, with UVPD of the core OS producing an extensive array of cross-ring cleavage fragments. Successful discernment of E. coli R-LPS structures with isomeric core structures confirmed the degree to which subtle structural differences could be determined using this method.
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Affiliation(s)
- Dustin R Klein
- Department of Chemistry, The University of Texas at Austin , Austin, Texas 78712, United States
| | - Dustin D Holden
- Department of Chemistry, The University of Texas at Austin , Austin, Texas 78712, United States
| | - Jennifer S Brodbelt
- Department of Chemistry, The University of Texas at Austin , Austin, Texas 78712, United States
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Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: an update for 2009-2010. MASS SPECTROMETRY REVIEWS 2015; 34:268-422. [PMID: 24863367 PMCID: PMC7168572 DOI: 10.1002/mas.21411] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 07/16/2013] [Accepted: 07/16/2013] [Indexed: 05/07/2023]
Abstract
This review is the sixth update of the original article published in 1999 on the application of MALDI mass spectrometry to the analysis of carbohydrates and glycoconjugates and brings coverage of the literature to the end of 2010. General aspects such as theory of the MALDI process, matrices, derivatization, MALDI imaging, arrays and fragmentation are covered in the first part of the review and applications to various structural typed constitutes the remainder. The main groups of compound that are discussed in this section are oligo and polysaccharides, glycoproteins, glycolipids, glycosides and biopharmaceuticals. Many of these applications are presented in tabular form. Also discussed are medical and industrial applications of the technique, studies of enzyme reactions and applications to chemical synthesis.
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Affiliation(s)
- David J. Harvey
- Department of BiochemistryOxford Glycobiology InstituteUniversity of OxfordOxfordOX1 3QUUK
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Cooper CA, Mainprize IL, Nickerson NN. Genetic, Biochemical, and Structural Analyses of Bacterial Surface Polysaccharides. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2015; 883:295-315. [PMID: 26621474 DOI: 10.1007/978-3-319-23603-2_16] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Surface polysaccharides are an often essential component of the outer surface of bacteria. They may serve to protect organisms from harsh environmental conditions and to increase virulence. The focus of this review will be to introduce polysaccharide biosynthesis and export from the cell, and the associated techniques used to determine these glycostructures. Protein interactions and proteomics will then be discussed while introducing systems biology approaches used to determine protein-protein and protein-polysaccharide interactions. The final section will address related screening methods used to study gene regulation in bacteria relating to polysaccharide gene clusters and their associated regulators. The goal of this review will be to highlight key studies that have increased our knowledge of glycobiology and discuss novel methods that examine this field at the cellular level using systems biology.
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Affiliation(s)
- Colin A Cooper
- Agriculture and Food Laboratory, Laboratory Services, University of Guelph, 95 Stone Rd. W., Guelph, ON, N1H 8J7, Canada.
| | - Iain L Mainprize
- Department of Molecular and Cellular Biology, University of Guelph, 95 Stone Road, Guelph, ON, N1H 8J7, Canada
| | - Nicholas N Nickerson
- Department of Molecular and Cellular Biology, University of Guelph, 95 Stone Road, Guelph, ON, N1H 8J7, Canada.,Department of Infectious Diseases, Genentech Inc., South San Francisco, CA, 94080, USA
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Martín-Sómer A, Yáñez M, Gaigeot MP, Spezia R. Unimolecular Fragmentation Induced By Low-Energy Collision: Statistically or Dynamically Driven? J Phys Chem A 2014; 118:10882-93. [DOI: 10.1021/jp5076059] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Ana Martín-Sómer
- Departamento
de Química, Facultad de Ciencias, Módulo
13. Universidad Autónoma de Madrid, Campus de Excelencia UAM-CSIC. Cantoblanco, E-28049 Madrid, Spain
- Université d’Evry Val d’Essonne, UMR 8587 LAMBE, Boulevard F. Mitterrand, 91025 Evry Cedex, France
| | - Manuel Yáñez
- Departamento
de Química, Facultad de Ciencias, Módulo
13. Universidad Autónoma de Madrid, Campus de Excelencia UAM-CSIC. Cantoblanco, E-28049 Madrid, Spain
| | - Marie-Pierre Gaigeot
- Université d’Evry Val d’Essonne, UMR 8587 LAMBE, Boulevard F. Mitterrand, 91025 Evry Cedex, France
- CNRS, Laboratoire Analyse
et Modélisation pour la Biologie et
l’Environnement, UMR 8587, Boulevard
F. Mitterrand, 91025 Evry Cedex, France
- Institut Universitaire de France (IUF), 103 Blvd St Michel, 75005 Paris, France
| | - Riccardo Spezia
- Université d’Evry Val d’Essonne, UMR 8587 LAMBE, Boulevard F. Mitterrand, 91025 Evry Cedex, France
- CNRS, Laboratoire Analyse
et Modélisation pour la Biologie et
l’Environnement, UMR 8587, Boulevard
F. Mitterrand, 91025 Evry Cedex, France
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O'Brien JP, Needham BD, Henderson JC, Nowicki EM, Trent MS, Brodbelt JS. 193 nm ultraviolet photodissociation mass spectrometry for the structural elucidation of lipid A compounds in complex mixtures. Anal Chem 2014; 86:2138-45. [PMID: 24446701 PMCID: PMC3958132 DOI: 10.1021/ac403796n] [Citation(s) in RCA: 45] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
![]()
Here we implement ultraviolet photodissociation
(UVPD) in an online
liquid chromatographic tandem mass spectrometry (MS/MS) strategy to
support analysis of complex mixtures of lipid A combinatorially modified
during development of vaccine adjuvants. UVPD mass spectrometry at
193 nm was utilized to characterize the structures and fragment ion
types of lipid A from Escherichia coli, Vibrio
cholerae, and Pseudomonas aeruginosa using
an Orbitrap mass spectrometer. The fragment ions generated by UVPD
were compared to those from collision induced dissociation (CID) and
higher energy collision dissociation (HCD) with respect to the precursor
charge state. UVPD afforded the widest array of fragment ion types
including acyl chain C–O, C–N, and C–C bond cleavages
and glycosidic C–O and cross ring cleavages, thus providing
the most comprehensive structural analysis of the lipid A. UVPD exhibited
virtually no dependence on precursor ion charge state and was best
at determining lipid A structure including acyl chain length and composition,
giving it an advantage over collision based methods. UVPD was incorporated
into an LC–MS/MS methodology for the analysis of a number of
structural variants in a complex mixture of combinatorially engineered Escherichia coli lipid A.
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Affiliation(s)
- John P O'Brien
- Department of Chemistry, The University of Texas at Austin , 1 University Station A5300, Austin, Texas 78712, United States
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Henderson JC, O'Brien JP, Brodbelt JS, Trent MS. Isolation and chemical characterization of lipid A from gram-negative bacteria. J Vis Exp 2013:e50623. [PMID: 24084191 DOI: 10.3791/50623] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023] Open
Abstract
Lipopolysaccharide (LPS) is the major cell surface molecule of gram-negative bacteria, deposited on the outer leaflet of the outer membrane bilayer. LPS can be subdivided into three domains: the distal O-polysaccharide, a core oligosaccharide, and the lipid A domain consisting of a lipid A molecular species and 3-deoxy-D-manno-oct-2-ulosonic acid residues (Kdo). The lipid A domain is the only component essential for bacterial cell survival. Following its synthesis, lipid A is chemically modified in response to environmental stresses such as pH or temperature, to promote resistance to antibiotic compounds, and to evade recognition by mediators of the host innate immune response. The following protocol details the small- and large-scale isolation of lipid A from gram-negative bacteria. Isolated material is then chemically characterized by thin layer chromatography (TLC) or mass-spectrometry (MS). In addition to matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) MS, we also describe tandem MS protocols for analyzing lipid A molecular species using electrospray ionization (ESI) coupled to collision induced dissociation (CID) and newly employed ultraviolet photodissociation (UVPD) methods. Our MS protocols allow for unequivocal determination of chemical structure, paramount to characterization of lipid A molecules that contain unique or novel chemical modifications. We also describe the radioisotopic labeling, and subsequent isolation, of lipid A from bacterial cells for analysis by TLC. Relative to MS-based protocols, TLC provides a more economical and rapid characterization method, but cannot be used to unambiguously assign lipid A chemical structures without the use of standards of known chemical structure. Over the last two decades isolation and characterization of lipid A has led to numerous exciting discoveries that have improved our understanding of the physiology of gram-negative bacteria, mechanisms of antibiotic resistance, the human innate immune response, and have provided many new targets in the development of antibacterial compounds.
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Affiliation(s)
- Jeremy C Henderson
- Section of Molecular Genetics and Microbiology, The University of Texas at Austin
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31
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Zdybicka-Barabas A, Stączek S, Mak P, Skrzypiec K, Mendyk E, Cytryńska M. Synergistic action of Galleria mellonella apolipophorin III and lysozyme against Gram-negative bacteria. BIOCHIMICA ET BIOPHYSICA ACTA-BIOMEMBRANES 2013; 1828:1449-56. [DOI: 10.1016/j.bbamem.2013.02.004] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/25/2012] [Revised: 01/14/2013] [Accepted: 02/08/2013] [Indexed: 12/14/2022]
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Kilár A, Dörnyei Á, Kocsis B. Structural characterization of bacterial lipopolysaccharides with mass spectrometry and on- and off-line separation techniques. MASS SPECTROMETRY REVIEWS 2013; 32:90-117. [PMID: 23165926 DOI: 10.1002/mas.21352] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2011] [Revised: 03/27/2012] [Accepted: 03/27/2012] [Indexed: 06/01/2023]
Abstract
The focus of this review is the application of mass spectrometry to the structural characterization of bacterial lipopolysaccharides (LPSs), also referred to as "endotoxins," because they elicit the strong immune response in infected organisms. Recently, a wide variety of MS-based applications have been implemented to the structure elucidation of LPS. Methodological improvements, as well as on- and off-line separation procedures, proved the versatility of mass spectrometry to study complex LPS mixtures. Special attention is given in the review to the tandem mass spectrometric methods and protocols for the analyses of lipid A, the endotoxic principle of LPS. We compare and evaluate the different ionization techniques (MALDI, ESI) in view of their use in intact R- and S-type LPS and lipid A studies. Methods for sample preparation of LPS prior to mass spectrometric analysis are also described. The direct identification of intrinsic heterogeneities of most intact LPS and lipid A preparations is a particular challenge, for which separation techniques (e.g., TLC, slab-PAGE, CE, GC, HPLC) combined with mass spectrometry are often necessary. A brief summary of these combined methodologies to profile LPS molecular species is provided.
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Affiliation(s)
- Anikó Kilár
- Department of Analytical and Environmental Chemistry, Institute of Chemistry, Faculty of Sciences, University of Pécs, Pécs, Hungary.
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33
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The outer membrane of Gram-negative bacteria: lipid A isolation and characterization. Methods Mol Biol 2013; 966:239-258. [PMID: 23299739 DOI: 10.1007/978-1-62703-245-2_15] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The isolation and characterization of the lipid A domain of lipopolysaccharide (LPS) are important methodologies utilized to gain understanding of the Gram-negative cell envelope. Here, we describe protocols often employed by our laboratory for small- and large-scale isolation of lipid A from bacterial cells. Additionally, we describe various methodologies including isolation of radiolabeled lipid A, thin layer chromatography, and various mass spectrometry methods. Tandem mass spectrometry is an integral tool for the structural characterization of lipid A molecules, and both coventional collision induced dissociation (CID) and new ultraviolet photodissociation (UVPD) methods are described.
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Gnanadhas DP, Marathe SA, Chakravortty D. Biocides--resistance, cross-resistance mechanisms and assessment. Expert Opin Investig Drugs 2012; 22:191-206. [PMID: 23215733 DOI: 10.1517/13543784.2013.748035] [Citation(s) in RCA: 67] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
IMPORTANCE OF THE FIELD Antibiotic resistance in bacterial pathogens has increased worldwide leading to treatment failures. Concerns have been raised about the use of biocides as a contributing factor to the risk of antimicrobial resistance (AMR) development. In vitro studies demonstrating increase in resistance have often been cited as evidence for increased risks. It is therefore important to understand the mechanisms of resistance employed by bacteria toward biocides used in consumer products and their potential to impart cross-resistance to therapeutic antibiotics. AREAS COVERED In this review, the mechanisms of resistance and cross-resistance reported in the literature toward biocides commonly used in consumer products are summarized. The physiological and molecular techniques used in describing and examining these mechanisms are reviewed and application of these techniques for systematic assessment of biocides for their potential to develop resistance and/or cross-resistance is discussed. EXPERT OPINION The guidelines in the usage of biocides in household or industrial purpose should be monitored and regulated to avoid the emergence of any MDR strains. The genetic and molecular methods to monitor the resistance development to biocides should be developed and included in preclinical and clinical studies.
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Affiliation(s)
- Divya Prakash Gnanadhas
- Department of Microbiology and Cell Biology, Centre for Infectious Disease Research and Biosafety Laboratories, Indian Institute of Science, Bangalore 560012, India
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35
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Casabuono AC, van der Ploeg CA, Rogé AD, Bruno SB, Couto AS. Characterization of lipid A profiles from Shigella flexneri variant X lipopolysaccharide. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2012; 26:2011-2020. [PMID: 22847700 DOI: 10.1002/rcm.6306] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
RATIONALE In developing countries, Shigella flexneri (Sf) is the major causative agent of the endemic shigellosis (bacillary dysentery) responsible annually for one million fatalities mostly among infants. Lipopolysaccharides (LPSs) are characteristic components of the outer membrane of the overwhelming majority of Gram-negative bacteria. Since lipid A is essential for the viability of the Gram-negative bacteria, it is subject to extensive chemical studies with new analytical techniques. METHODS Lipid A was released by mild acid hydrolysis from the lipopolysaccharide which was obtained via the phenol/water extraction, purified and analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and matrix-assisted laser desorption/ionization laser-induced dissociation tandem mass spectrometry (MALDI-LID-MS/MS). RESULTS A detailed structural study of the whole lipid A obtained from S. flexneri variant X was carried out for the first time. Thus, we have shown that lipid A is a heterogeneous mixture having different numbers of acylated and phosphoethanolamine groups attached to the diglucosamine backbone. Furthermore, we found in the phenol phase an unusual hepta-acylated lipid A species, although the abundance was very low. CONCLUSIONS MALDI-TOF-MS allowed us to unravel the lipid A heterogeneity, which was not previously reported in Sf LPS. It is well known that slight variations of the chemical structure of lipid A may change its biological activity. Thus, the knowledge of the detailed chemical structure represents an essential step for further development of new preventive or therapeutically active compounds.
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Affiliation(s)
- Adriana C Casabuono
- CIHIDECAR, Departamento de Química Orgánica, Facultad de Cs Exactas y Naturales, Universidad de Buenos Aires, Pabellón II, Cdad. Universitaria, Bs. As., Argentina
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36
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Costello CM, Yeung CL, Rawson FJ, Mendes PM. Application of nanotechnology to control bacterial adhesion and patterning on material surfaces. JOURNAL OF EXPERIMENTAL NANOSCIENCE 2012; 7:634-651. [PMID: 24273593 PMCID: PMC3836354 DOI: 10.1080/17458080.2012.740640] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/18/2012] [Revised: 10/13/2012] [Indexed: 06/02/2023]
Abstract
Bacterial adhesion and biofilm formation on surfaces raises health hazard issues in the medical environment. Previous studies of bacteria adhesion have focused on observations in their natural/native environments. Recently, surface science has contributed in advancing the understanding of bacterial adhesion by providing ideal platforms that attempt to mimic the bacteria's natural environments, whilst also enabling concurrent control, selectivity and spatial control of bacterial adhesion. In this review, we will look at techniques of how nanotechnology is used to control cell adhesion on a planar scale, in addition to describing the use of nanotools for cell micropatterning. Additionally, it will provide a general background of common methods for nanoscale modification enabling biologist unfamiliar with nanotechnology to enter the field.
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Affiliation(s)
- Cait M. Costello
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Chun L. Yeung
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Frankie J. Rawson
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
| | - Paula M. Mendes
- School of Chemical Engineering, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK
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37
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Abstract
Endotoxin, an outer membrane component of gram-negative bacteria, plays an important role in the pathogenesis of septic shock. Endotoxin adsorption therapy by polymyxin B-immobilized fiber column hemoperfusion (PMX) has been used for the treatment of septic shock patients in Japan since 1994. The covalent binding of polymyxin B onto the surface of the polystyrene-based carrier fiber in PMX inactivates the endotoxin in the blood without exerting toxicity. This study was performed as a systematic review to evaluate the efficacy and mechanism of PMX treatment in patients with septic shock. The PubMed database and references from identified articles were used to search and review the literature relating to the efficacy and mechanism of PMX treatment in patients with septic shock. Polymyxin B-immobilized fiber column hemoperfusion adsorbed monocytes, activated neutrophils, and anandamide, as well as endotoxin through direct covalent bond, hydrophobic and ionic interactions, and hydrodynamics, and reduced the blood concentrations of inflammatory cytokines, plasminogen activator inhibitor 1 and adhesion molecules. Polymyxin B-immobilized fiber column hemoperfusion increased blood pressure and reduced the dosage requirements for vasopressive/inotropic agents. The meta-analysis showed that PMX treatment had beneficial effects on the hemodynamics, pulmonary oxygenation, and mortality. These beneficial effects may be attributable to the direct adsorption of endotoxin, monocytes, activated neutrophils, and anandamide, as well as indirect decrease in inflammatory cytokines and other mediators. Polymyxin B-immobilized fiber column hemoperfusion treatment has additional effects on reducing endothelial damage, proapoptotic activity, and immunosuppression. Further studies will be needed to confirm the efficacy and mechanism of PMX treatment in septic shock.
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38
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Post DMB, Yu L, Krasity BC, Choudhury B, Mandel MJ, Brennan CA, Ruby EG, McFall-Ngai MJ, Gibson BW, Apicella MA. O-antigen and core carbohydrate of Vibrio fischeri lipopolysaccharide: composition and analysis of their role in Euprymna scolopes light organ colonization. J Biol Chem 2012; 287:8515-30. [PMID: 22247546 DOI: 10.1074/jbc.m111.324012] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Vibrio fischeri exists in a symbiotic relationship with the Hawaiian bobtail squid, Euprymna scolopes, where the squid provides a home for the bacteria, and the bacteria in turn provide camouflage that helps protect the squid from night-time predators. Like other gram-negative organisms, V. fischeri expresses lipopolysaccharide (LPS) on its cell surface. The structure of the O-antigen and the core components of the LPS and their possible role in colonization of the squid have not previously been determined. In these studies, an O-antigen ligase mutant, waaL, was utilized to determine the structures of these LPS components and their roles in colonization of the squid. WaaL ligates the O-antigen to the core of the LPS; thus, LPS from waaL mutants lacks O-antigen. Our results show that the V. fischeri waaL mutant has a motility defect, is significantly delayed in colonization, and is unable to compete with the wild-type strain in co-colonization assays. Comparative analyses of the LPS from the wild-type and waaL strains showed that the V. fischeri LPS has a single O-antigen repeat composed of yersiniose, 8-epi-legionaminic acid, and N-acetylfucosamine. In addition, the LPS from the waaL strain showed that the core structure consists of L-glycero-D-manno-heptose, D-glycero-D-manno-heptose, glucose, 3-deoxy-D-manno-octulosonic acid, N-acetylgalactosamine, 8-epi-legionaminic acid, phosphate, and phosphoethanolamine. These studies indicate that the unusual V. fischeri O-antigen sugars play a role in the early phases of bacterial colonization of the squid.
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Affiliation(s)
- Deborah M B Post
- Buck Institute for Research on Aging, Novato, California 94945, USA
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Safina G. Application of surface plasmon resonance for the detection of carbohydrates, glycoconjugates, and measurement of the carbohydrate-specific interactions: A comparison with conventional analytical techniques. A critical review. Anal Chim Acta 2012; 712:9-29. [DOI: 10.1016/j.aca.2011.11.016] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2011] [Revised: 10/07/2011] [Accepted: 11/04/2011] [Indexed: 12/16/2022]
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Nazarenko EL, Crawford RJ, Ivanova EP. The structural diversity of carbohydrate antigens of selected gram-negative marine bacteria. Mar Drugs 2011; 9:1914-1954. [PMID: 22073003 PMCID: PMC3210612 DOI: 10.3390/md9101914] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2011] [Revised: 09/07/2011] [Accepted: 09/13/2011] [Indexed: 11/16/2022] Open
Abstract
Marine microorganisms have evolved for millions of years to survive in the environments characterized by one or more extreme physical or chemical parameters, e.g., high pressure, low temperature or high salinity. Marine bacteria have the ability to produce a range of biologically active molecules, such as antibiotics, toxins and antitoxins, antitumor and antimicrobial agents, and as a result, they have been a topic of research interest for many years. Among these biologically active molecules, the carbohydrate antigens, lipopolysaccharides (LPSs, O-antigens) found in cell walls of gram-negative marine bacteria, show great potential as candidates in the development of drugs to prevent septic shock due to their low virulence. The structural diversity of LPSs is thought to be a reflection of the ability for these bacteria to adapt to an array of habitats, protecting the cell from being compromised by exposure to harsh environmental stress factors. Over the last few years, the variety of structures of core oligosaccharides and O-specific polysaccharides from LPSs of marine microrganisms has been discovered. In this review, we discuss the most recently encountered structures that have been identified from bacteria belonging to the genera Aeromonas, Alteromonas, Idiomarina, Microbulbifer, Pseudoalteromonas, Plesiomonas and Shewanella of the Gammaproteobacteria phylum; Sulfitobacter and Loktanella of the Alphaproteobactera phylum and to the genera Arenibacter, Cellulophaga, Chryseobacterium, Flavobacterium, Flexibacter of the Cytophaga-Flavobacterium-Bacteroides phylum. Particular attention is paid to the particular chemical features of the LPSs, such as the monosaccharide type, non-sugar substituents and phosphate groups, together with some of the typifying traits of LPSs obtained from marine bacteria. A possible correlation is then made between such features and the environmental adaptations undertaken by marine bacteria.
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Affiliation(s)
- Evgeny L. Nazarenko
- Pacific Institute of Bioorganic Chemistry, Far East Branch of the Russian Academy of Sciences, Vladivostok 690022, Russia; E-Mail:
| | - Russell J. Crawford
- Faculty of Life and Social Sciences, Swinburne University of Technology, PO Box 218, Hawthorn, Victoria 3122, Australia; E-Mail:
| | - Elena P. Ivanova
- Faculty of Life and Social Sciences, Swinburne University of Technology, PO Box 218, Hawthorn, Victoria 3122, Australia; E-Mail:
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Use of 3-hydroxy fatty acid concentrations in a murine air pouch infection model as a surrogate marker for LPS activity: a feasibility study using environmental Burkholderia cenocepacia isolates. J Microbiol Methods 2011; 87:368-74. [PMID: 22008505 DOI: 10.1016/j.mimet.2011.10.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2011] [Revised: 10/03/2011] [Accepted: 10/03/2011] [Indexed: 11/20/2022]
Abstract
Using a murine hypodermic air pouch infection model designed to mimic the release of bacterial products at physiological levels, 3-hydroxy fatty acid (3-OH FA) and endotoxin unit levels from Burkholderia cenocepacia isolates were assessed. The B. cenocepacia environmental isolates (n=35) survived in the hypodermic air pouch but did not invade across the peritoneal epithelial layer during a 72-h infection. For all 35 strains, when the molar ratio of C(14:0) 3-OH FA to C(16:0) 3-OH FA in the air pouch fluid wash samples was between 1.4 and 2.5, the concentrations of C(14:0) 3-OH FA were correlated with the endotoxin unit levels. However, both surrogate markers exhibited different correlations to the inflammatory response. The linear regression coefficient was 0.4234 for C(14:0) 3-OH FA concentrations vs. NO productions, 0.223 for endotoxin unit levels vs. NO productions, 0.5008 for C(14:0) 3-OH FA concentrations vs. TNF-alpha productions and 0.2869 for endotoxin unit levels vs. TNF-alpha productions. Therefore, C(14:0) 3-OH FA concentrations, rather than endotoxin unit levels, acted as an immunostimulatory indicator for LPS in the B. cenocepacia isolates.
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Madsen JA, Cullen TW, Trent MS, Brodbelt JS. IR and UV photodissociation as analytical tools for characterizing lipid A structures. Anal Chem 2011; 83:5107-13. [PMID: 21595441 PMCID: PMC3128199 DOI: 10.1021/ac103271w] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The utility of 193-nm ultraviolet photodissociation (UVPD) and 10.6-μm infrared multiphoton dissociation (IRMPD) for the characterization of lipid A structures was assessed in an ion trap mass spectrometer. The fragmentation behavior of lipid A species was also evaluated by activated-electron photodetachment (a-EPD), which uses 193-nm photons to create charge reduced radicals that are subsequently dissociated by collisional activation. In contrast to collision-induced dissociation (CID), IRMPD offered the ability to selectively differentiate product ions with varying degrees of phosphorylation because of the increased photoabsorption cross sections and thus dissociation of phosphate-containing species. Both 193-nm UVPD and a-EPD yielded higher abundances and a larger array of product ions arising from C-C cleavages, as well as cross-ring and inter-ring glucosamine cleavages, compared to CID and IRMPD, because of high energy, single-photon absorption, and/or radical-directed dissociation. UVPD at 193 nm also exhibited enhanced cleavage between the amine and carbonyl groups on the 2- and 2'-linked primary acyl chains. Lastly, UVPD of phosphorylethanolamine-modified lipid A species resulted in preferential cleavage of the C-O bond between ethanolamine and phosphate, enabling the selective identification of this modification.
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Affiliation(s)
- James A. Madsen
- Department of Chemistry and Biochemistry, The University of Texas at Austin, 1 University Station A5300, Austin, TX, USA 78712
| | - Thomas W. Cullen
- Section of Molecular Genetics and Microbiology, The University of Texas at Austin, Austin, TX, USA 78712
| | - M. Stephen Trent
- Section of Molecular Genetics and Microbiology, The University of Texas at Austin, Austin, TX, USA 78712
- The Institute of Cellular and Molecular Biology, The University of Texas at Austin, Austin, TX, USA 78712
| | - Jennifer S. Brodbelt
- Department of Chemistry and Biochemistry, The University of Texas at Austin, 1 University Station A5300, Austin, TX, USA 78712
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Fidalgo AR, Cibelli M, White JP, Nagy I, Maze M, Ma D. Systemic inflammation enhances surgery-induced cognitive dysfunction in mice. Neurosci Lett 2011; 498:63-6. [DOI: 10.1016/j.neulet.2011.04.063] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2010] [Revised: 03/14/2011] [Accepted: 04/23/2011] [Indexed: 10/18/2022]
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Aiello D, De Luca D, Gionfriddo E, Naccarato A, Napoli A, Romano E, Russo A, Sindona G, Tagarelli A. Review: multistage mass spectrometry in quality, safety and origin of foods. EUROPEAN JOURNAL OF MASS SPECTROMETRY (CHICHESTER, ENGLAND) 2011; 17:1-31. [PMID: 21625027 DOI: 10.1255/ejms.1114] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
Quality and safety control and the validation of origin are hot issues in the production of food and its distribution, and are of primary concern to food and agriculture organization. Modern mass spectrometry (MS) provides unique, reliable and affordable methodologies to approach with a high degree of scientificity any problem which may be posed in this field. In this review the contribution of mass spectrometry to food analysis is presented aiming at providing clues on the fundamental role of the basic principles of gas-phase ion chemistry in applied research fields. Applications in proteomics, allergonomics, glycomics, metabolomics, lipidomics, food safety and traceability have been surveyed. The high level of specificity and sensitivity of the MS approach allows the characterization of food components and contaminants present at ultra-trace levels, providing a distinctive and safe validation of the products.
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Affiliation(s)
- Donatella Aiello
- Dipartimento di Chimica, Università della Calabria, Arcavacata di Rende, Italy
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Kilár A, Dörnyei Á, Bui A, Szabó Z, Kocsis B, Kilár F. Structural variability of endotoxins from R-type isogenic mutants of Shigella sonnei. JOURNAL OF MASS SPECTROMETRY : JMS 2011; 46:61-70. [PMID: 21184397 DOI: 10.1002/jms.1863] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
The structural variations in the rough-type endotoxins [lipopolysaccharides (LPSs)] of Shigella sonnei mutant strains (S. sonnei phase II-4303, R41, 562H and 4350) were investigated by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and tandem MS. A series of S. sonnei mutants had previously been the subject of analytical studies on the biosynthesis of heptose components in the core oligosaccharide region of LPSs. This study gives a complete overview on the structures of the full core and lipid A of S. sonnei mutant strains by MS. We found that the LPSs of the isogenic rough mutants were formed in a step-like manner containing 0:1:2:3 heptose in the deep core region of 4350, 562H, R41 and 4303, respectively, and the longest LPS from the mutant S. sonnei 4303 contained also five hexoses. The structural variations in the lipid A moiety and in the oligosaccharide part of the intact LPS were followed by MALDI-TOF-MS/MS. For the dissolution and the ionization of the samples, 2,5-dihydroxybenzoic acid in citric acid solution was applied as matrix. The detailed evaluation of the mass spectra indicates heterogeneity in the lipid part due to the differences in the phosphate and fatty acid composition.
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Affiliation(s)
- Anikó Kilár
- Department of Analytical and Environmental Chemistry, Faculty of Sciences, University of Pécs, Ifjúság útja 6, H-7624 Pécs, Hungary
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