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Chakraborty A, Alsharqi L, Kostrzewa M, Armstrong-James D, Larrouy-Maumus G. Intact cell lipidomics using the Bruker MBT lipid Xtract assay allows the rapid detection of glycosyl-inositol-phospho-ceramides from Aspergillus fumigatus. Mol Omics 2024. [PMID: 38623711 DOI: 10.1039/d4mo00030g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2024]
Abstract
Glycosyl-inositol-phospho-ceramides (GIPCs) or glycosylphosphatidylinositol-anchored fungal polysaccharides are major lipids in plant and fungal plasma membranes and play an important role in stress adaption. However, their analysis remains challenging due to the multiple steps involved in their extraction and purification prior to mass spectrometry analysis. To address this challenge, we report here a novel simplified method to identify GIPCs from Aspergillus fumigatus using the new Bruker MBT lipid Xtract assay. A. fumigatus reference strains and clinical isolates were cultured, harvested, heat-inactivated and suspended in double-distilled water. A fraction of this fungal preparation was then dried in a microtube, mixed with an MBT lipid Xtract matrix (Bruker Daltonik, Germany) and loaded onto a MALDI target plate. Analysis was performed using a Bruker MALDI Biotyper Sirius system in the linear negative ion mode. Mass spectra were scanned from m/z 700 to m/z 2 000. MALDI-TOF MS analysis of cultured fungi showed a clear signature of GIPCs in Aspergillus fumigatus reference strains and clinical isolates. Here, we have demonstrated that routine MALDI-TOF in the linear negative ion mode combined with the MBT lipid Xtract is able to detect Aspergillus fumigatus GIPCs.
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Affiliation(s)
- Aishani Chakraborty
- Centre for Bacterial Resistance Biology, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, SW7 2AZ, UK.
| | - Leila Alsharqi
- Centre for Bacterial Resistance Biology, Department of Infectious Diseases, Faculty of Medicine, Imperial College London, London, SW7 2AZ, UK.
| | | | - Darius Armstrong-James
- Centre for Bacterial Resistance Biology, Department of Infectious Diseases, Faculty of Medicine, Imperial College London, London, SW7 2AZ, UK.
| | - Gerald Larrouy-Maumus
- Centre for Bacterial Resistance Biology, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, SW7 2AZ, UK.
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John CM, Phillips NJ, Cardenas AJ, Criss AK, Jarvis GA. Comparison of lipooligosaccharides from human challenge strains of Neisseria gonorrhoeae. Front Microbiol 2023; 14:1215946. [PMID: 37779694 PMCID: PMC10540682 DOI: 10.3389/fmicb.2023.1215946] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/02/2023] [Accepted: 08/23/2023] [Indexed: 10/03/2023] Open
Abstract
The alarming rise of antibiotic resistance and the emergence of new vaccine technologies have increased the focus on vaccination to control gonorrhea. Neisseria gonorrhoeae strains FA1090 and MS11 have been used in challenge studies in human males. We used negative-ion MALDI-TOF MS to profile intact lipooligosaccharide (LOS) from strains MS11mkA, MS11mkC, FA1090 A23a, and FA1090 1-81-S2. The MS11mkC and 1-81-S2 variants were isolated from male volunteers infected with MS11mkA and A23a, respectively. LOS profiles were obtained after purification using the classical phenol water extraction method and by microwave-enhanced enzymatic digestion, which is more amenable for small-scale work. Despite detecting some differences in the LOS profiles, the same major species were observed, indicating that microwave-enhanced enzymatic digestion is appropriate for MS studies. The compositions determined for MS11mkA and mkC LOS were consistent with previous reports. FA1090 is strongly recognized by mAb 2C7, an antibody-binding LOS with both α- and β-chains if the latter is a lactosyl group. The spectra of the A23a and 1-81-S2 FA1090 LOS were similar to each other and consistent with the expression of α-chain lacto-N-neotetraose and β-chain lactosyl moieties that can both be acceptor sites for sialic acid substitution. 1-81-S2 LOS was analyzed after culture with and without media supplemented with cytidine-5'-monophosphate N-acetylneuraminic acid (CMP-Neu5Ac), which N. gonorrhoeae needs to sialylate its LOS. LOS sialylation reduces the infectivity of gonococci in men, although it induces serum resistance in serum-sensitive strains and reduces killing by neutrophils and antimicrobial peptides. The infectivity of FA1090 in men is much lower than that of MS11mkC, but the reason for this difference is unclear. Interestingly, some peaks in the spectra of 1-81-S2 LOS after bacterial culture with CMP-Neu5Ac were consistent with disialylation of the LOS, which could be relevant to the reduced infectivity of FA1090 in men and could have implications regarding the phase variation of the LOS and the natural history of infection.
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Affiliation(s)
- Constance M. John
- Veterans Affairs Medical Center, San Francisco, CA, United States
- Department of Laboratory Medicine, University of California, San Francisco, San Francisco, CA, United States
| | - Nancy J. Phillips
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, United States
| | - Amaris J. Cardenas
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, United States
| | - Alison K. Criss
- Department of Microbiology, Immunology, and Cancer Biology, University of Virginia, Charlottesville, VA, United States
| | - Gary A. Jarvis
- Veterans Affairs Medical Center, San Francisco, CA, United States
- Department of Laboratory Medicine, University of California, San Francisco, San Francisco, CA, United States
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Bacteroides thetaiotaomicron rough-type lipopolysaccharide: The chemical structure and the immunological activity. Carbohydr Polym 2022; 297:120040. [DOI: 10.1016/j.carbpol.2022.120040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2022] [Revised: 08/20/2022] [Accepted: 08/23/2022] [Indexed: 11/20/2022]
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Garcia-Vello P, Speciale I, Di Lorenzo F, Molinaro A, De Castro C. Dissecting Lipopolysaccharide Composition and Structure by GC-MS and MALDI Spectrometry. Methods Mol Biol 2022; 2548:181-209. [PMID: 36151499 DOI: 10.1007/978-1-0716-2581-1_12] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Abstract
Lipopolysaccharides (LPSs) are the main components of the external leaflet of the outer membrane of Gram-negative bacteria. They exert multiple functions, starting from conferring stability to the bacterial membrane to mediating the interaction of the microbe with the external environment. The composition and the structure of LPSs present tremendous diversity even within bacteria of the same species, and for this reason, the determination of the structure of these molecules is crucial because it can provide information on the motifs key for the virulence of a pathogen or that are associated to a bacterium of the commensal or beneficial microbiota. In addition, structural data disclose the effects triggered from a mutation or from the use of an antibiotic, or they can be used as tools to check the quality of adjuvants and/or medications, as vaccines, that make use of LPS.The structural study of LPSs is complex, and it can be achieved with the right combination of different techniques. In this frame, this chapter focuses on the two MS-based approaches, the gas chromatography-mass spectrometry (GC-MS) and the matrix-assisted laser desorption/ionization (MALDI).
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Affiliation(s)
| | - Immacolata Speciale
- Department of Chemical Sciences, University of Naples, Naples, Italy
- Department of Agricultural Sciences, University of Naples, Portici, Italy
| | | | - Antonio Molinaro
- Department of Chemical Sciences, University of Naples, Naples, Italy
| | - Cristina De Castro
- Department of Agricultural Sciences, University of Naples, Portici, Italy.
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Larrouy-Maumus G. Shotgun Bacterial Lipid A Analysis Using Routine MALDI-TOF Mass Spectrometry. Methods Mol Biol 2021; 2306:275-283. [PMID: 33954953 DOI: 10.1007/978-1-0716-1410-5_18] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
Abstract
Detection of bacterial lipids and particularly the lipid A, the lipid anchor of the lipopolysaccharide, can be very challenging and requires a certain level of expertise. Here, this chapter describes a straightforward and simple method for the analysis of bacterial lipid A. In addition, such approach, lipid fingerprint, has the potential to be applied to other bacteria such as mycobacteria.
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Affiliation(s)
- Gérald Larrouy-Maumus
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, UK.
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Saromi K, England P, Tang W, Kostrzewa M, Corran A, Woscholski R, Larrouy-Maumus G. Rapid glycosyl-inositol-phospho-ceramide fingerprint from filamentous fungal pathogens using the MALDI Biotyper Sirius system. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2020; 34:e8904. [PMID: 32700347 DOI: 10.1002/rcm.8904] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/14/2020] [Revised: 07/19/2020] [Accepted: 07/19/2020] [Indexed: 06/11/2023]
Abstract
RATIONALE Glycosyl-inositol-phospho-ceramides (GIPCs) or glycosylphosphatidylinositol-anchored fungal polysaccharides are known to be major lipids in plant and fungal plasma membranes and to play an important role in stress adaption. However, their analysis remains challenging due to the several steps involved for their extractions and purifications prior to mass spectrometric analysis. To address this challenge, we developed a rapid and sensitive method to identify GIPCs from the four common fungal plant pathogens Botrytis cinerea, Fusarium graminearium, Neurospora crassa and Ustilago maydis. METHODS Fungal plant pathogens were cultured, harvested, heat-inactivated and washed three times with double-distilled water. Intact fungi were deposited on a matrix-assisted laser desorption ionization (MALDI) target plate, mixed with the matrix consisting of a 9:1 mixture of 2,5-dihydroxybenzoic acid and 2-hydroxy-5-methoxybenzoic acid solubilized at 10 mg/mL in chloroform-methanol (9:1 v/v) and analyzed using a Bruker MALDI Biotyper Sirius system in the linear negative ion mode. Mass spectra were acquired from m/z 700 to 2000. RESULTS MALDI time-of-flight (TOF) mass spectrometric analysis of cultured fungi showed clear signature of GIPCs in B. cinerea, F. graminearium, N. crassa and U. maydis. CONCLUSIONS We have demonstrated that routine MALDI-TOF in the linear negative ion mode combined with an apolar solvent system to solubilize the matrix is applicable to the detection of filamentous fungal GIPCs.
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Affiliation(s)
- Kofo Saromi
- Department of Chemistry, Faculty of Natural Sciences and Institute of Chemical Biology (ICB), Imperial College London, South Kensington Campus, London, SW7 2AZ, UK
| | - Philippa England
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, SW7 2AZ, UK
| | - Wenhao Tang
- Department of Mathematics, Imperial College London, London, SW7 2AZ, UK
| | | | - Andy Corran
- Syngenta Group, Bioscience, Jealott's Hill Research Station, Bracknell RG42 6EY, UK
| | - Rudiger Woscholski
- Department of Chemistry, Faculty of Natural Sciences and Institute of Chemical Biology (ICB), Imperial College London, South Kensington Campus, London, SW7 2AZ, UK
| | - Gerald Larrouy-Maumus
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, SW7 2AZ, UK
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John CM, Phillips NJ, Jarvis GA. Predominant phosphorylation patterns in Neisseria meningitidis lipid A determined by top-down MS/MS. J Lipid Res 2020; 61:1437-1449. [PMID: 32839198 DOI: 10.1194/jlr.ra120001014] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Among the virulence factors in Neisseria infections, a major inducer of inflammatory cytokines is the lipooligosaccharide (LOS). The activation of NF-κB via extracellular binding of LOS or lipopolysaccharide (LPS) to the toll-like receptor 4 and its coreceptor, MD-2, results in production of pro-inflammatory cytokines that initiate adaptive immune responses. LOS can also be absorbed by cells and activate intracellular inflammasomes, causing the release of inflammatory cytokines and pyroptosis. Studies of LOS and LPS have shown that their inflammatory potential is highly dependent on lipid A phosphorylation and acylation, but little is known on the location and pattern of these posttranslational modifications. Herein, we report on the localization of phosphoryl groups on phosphorylated meningococcal lipid A, which has two to three phosphate and zero to two phosphoethanolamine substituents. Intact LOS with symmetrical hexa-acylated and asymmetrical penta-acylated lipid A moieties was subjected to high-resolution ion mobility spectrometry MALDI-TOF MS. LOS molecular ions readily underwent in-source decay to give fragments of the oligosaccharide and lipid A formed by cleavage of the ketosidic linkage, which enabled performing MS/MS (pseudo-MS3). The resulting spectra revealed several patterns of phosphoryl substitution on lipid A, with certain species predominating. The extent of phosphoryl substitution, particularly phosphoethanolaminylation, on the 4'-hydroxyl was greater than that on the 1-hydroxyl. The heretofore unrecognized phosphorylation patterns of lipid A of meningococcal LOS that we detected are likely determinants of both pathogenicity and the ability of the bacteria to evade the innate immune system.
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Affiliation(s)
- Constance M John
- Center for Immunochemistry, Veterans Affairs Medical Center, San Francisco, CA, USA.,Department of Laboratory Medicine, University of California, San Francisco, San Francisco, CA, USA
| | - Nancy J Phillips
- Department of Pharmaceutical Chemistry, University of California, San Francisco, San Francisco, CA, USA
| | - Gary A Jarvis
- Center for Immunochemistry, Veterans Affairs Medical Center, San Francisco, CA, USA .,Department of Laboratory Medicine, University of California, San Francisco, San Francisco, CA, USA
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Di Lorenzo F, Speciale I, Silipo A, Alías-Villegas C, Acosta-Jurado S, Rodríguez-Carvajal MÁ, Dardanelli MS, Palmigiano A, Garozzo D, Ruiz-Sainz JE, Molinaro A, Vinardell JM. Structure of the unusual Sinorhizobium fredii HH103 lipopolysaccharide and its role in symbiosis. J Biol Chem 2020; 295:10969-10987. [PMID: 32546484 PMCID: PMC7415993 DOI: 10.1074/jbc.ra120.013393] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2020] [Revised: 06/11/2020] [Indexed: 11/06/2022] Open
Abstract
Rhizobia are soil bacteria that form important symbiotic associations with legumes, and rhizobial surface polysaccharides, such as K-antigen polysaccharide (KPS) and lipopolysaccharide (LPS), might be important for symbiosis. Previously, we obtained a mutant of Sinorhizobium fredii HH103, rkpA, that does not produce KPS, a homopolysaccharide of a pseudaminic acid derivative, but whose LPS electrophoretic profile was indistinguishable from that of the WT strain. We also previously demonstrated that the HH103 rkpLMNOPQ operon is responsible for 5-acetamido-3,5,7,9-tetradeoxy-7-(3-hydroxybutyramido)-l-glycero-l-manno-nonulosonic acid [Pse5NAc7(3OHBu)] production and is involved in HH103 KPS and LPS biosynthesis and that an HH103 rkpM mutant cannot produce KPS and displays an altered LPS structure. Here, we analyzed the LPS structure of HH103 rkpA, focusing on the carbohydrate portion, and found that it contains a highly heterogeneous lipid A and a peculiar core oligosaccharide composed of an unusually high number of hexuronic acids containing β-configured Pse5NAc7(3OHBu). This pseudaminic acid derivative, in its α-configuration, was the only structural component of the S. fredii HH103 KPS and, to the best of our knowledge, has never been reported from any other rhizobial LPS. We also show that Pse5NAc7(3OHBu) is the complete or partial epitope for a mAb, NB6-228.22, that can recognize the HH103 LPS, but not those of most of the S. fredii strains tested here. We also show that the LPS from HH103 rkpM is identical to that of HH103 rkpA but devoid of any Pse5NAc7(3OHBu) residues. Notably, this rkpM mutant was severely impaired in symbiosis with its host, Macroptilium atropurpureum.
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Affiliation(s)
- Flaviana Di Lorenzo
- Department of Chemical Sciences, University of Naples Federico II, Napoli, Italy
| | - Immacolata Speciale
- Department of Chemical Sciences, University of Naples Federico II, Napoli, Italy
| | - Alba Silipo
- Department of Chemical Sciences, University of Naples Federico II, Napoli, Italy
| | | | | | | | - Marta S Dardanelli
- Departamento de Biología Molecular, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto-INBIAS, CONICET, Córdoba, Argentina
| | - Angelo Palmigiano
- Istituto per i Polimeri, Compositi e Biomateriali IPCB, Consiglio Nazionale delle Ricerche, Catania, Italy
| | - Domenico Garozzo
- Istituto per i Polimeri, Compositi e Biomateriali IPCB, Consiglio Nazionale delle Ricerche, Catania, Italy
| | | | - Antonio Molinaro
- Department of Chemical Sciences, University of Naples Federico II, Napoli, Italy
| | - José-María Vinardell
- Department of Microbiology, Faculty of Biology, University of Seville, Sevilla, Spain
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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 DOI: 10.1021/acs.analchem.9b00940] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [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 , Texas 78712 , United States
| | - Matthew J Powers
- Department of Infectious Diseases , The University of Georgia, College of Veterinary Medicine , Athens , Georgia 30602 , United States.,Department of Microbiology , The University of Georgia, College of Arts and Sciences , Athens , Georgia 30602 , United States
| | - M Stephen Trent
- Department of Infectious Diseases , The University of Georgia, College of Veterinary Medicine , Athens , Georgia 30602 , United States.,Department of Microbiology , The University of Georgia, College of Arts and Sciences , Athens , Georgia 30602 , United States
| | - Jennifer S Brodbelt
- Department of Chemistry , The University of Texas at Austin , Austin , Texas 78712 , United States
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Structure and inflammatory activity of the LPS isolated from Acetobacter pasteurianus CIP103108. Int J Biol Macromol 2018; 119:1027-1035. [PMID: 30098357 DOI: 10.1016/j.ijbiomac.2018.08.035] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Revised: 08/06/2018] [Accepted: 08/07/2018] [Indexed: 12/30/2022]
Abstract
Acetobacter pasteurianus is an acetic acid-producing Gram-negative bacterium commonly found associated with plants and plant products and widely used in the production of fermented foods, such as kefir and vinegar. Due to the acid conditions of the bacterium living habitat, uncommon structural features composing its cell envelope are expected. In the present work we have investigated the A. pasteurianus CIP103108 lipopolysaccharide (LPS) structure and immunoactivity. The structure of the lipid A and of two different O-polysaccharides was assessed. Furthermore, immunological studies with human cells showed a low immunostimulant activity of the isolated LPS, in addition to a slight capability to lower the NF-kB activation upon stimulation by toxic LPS.
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Targeting the Bacterial Cytoskeleton of the Burkholderia cepacia Complex for Antimicrobial Development: A Cautionary Tale. Int J Mol Sci 2018; 19:ijms19061604. [PMID: 29848957 PMCID: PMC6032157 DOI: 10.3390/ijms19061604] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Revised: 05/04/2018] [Accepted: 05/17/2018] [Indexed: 11/18/2022] Open
Abstract
Burkholderia cepacia complex (BCC) bacteria are a group of opportunistic pathogens that cause severe lung infections in cystic fibrosis (CF). Treatment of BCC infections is difficult, due to the inherent and acquired multidrug resistance of BCC. There is a pressing need to find new bacterial targets for antimicrobials. Here, we demonstrate that the novel compound Q22, which is related to the bacterial cytoskeleton destabilising compound A22, can reduce the growth rate and inhibit growth of BCC bacteria. We further analysed the phenotypic effects of Q22 treatment on BCC virulence traits, to assess its feasibility as an antimicrobial. BCC bacteria were grown in the presence of Q22 with a broad phenotypic analysis, including resistance to H2O2-induced oxidative stress, changes in the inflammatory potential of cell surface components, and in-vivo drug toxicity studies. The influence of the Q22 treatment on inflammatory potential was measured by monitoring the cytokine responses of BCC whole cell lysates, purified lipopolysaccharide, and purified peptidoglycan extracted from bacterial cultures grown in the presence or absence of Q22 in differentiated THP-1 cells. BCC bacteria grown in the presence of Q22 displayed varying levels of resistance to H2O2-induced oxidative stress, with some strains showing increased resistance after treatment. There was strain-to-strain variation in the pro-inflammatory ability of bacterial lysates to elicit TNFα and IL-1β from human myeloid cells. Despite minimal toxicity previously shown in vitro with primary CF cell lines, in-vivo studies demonstrated Q22 toxicity in both zebrafish and mouse infection models. In summary, destabilisation of the bacterial cytoskeleton in BCC, using compounds such as Q22, led to increased virulence-related traits in vitro. These changes appear to vary depending on strain and BCC species. Future development of antimicrobials targeting the BCC bacterial cytoskeleton may be hampered if such effects translate into the in-vivo environment of the CF infection.
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Abstract
Lipopolysaccharide (LPS), a cell-associated glycolipid that makes up the outer leaflet of the outer membrane of Gram-negative bacteria, is a canonical mediator of microbe-host interactions. The most prevalent Gram-negative gut bacterial taxon, Bacteroides, makes up around 50% of the cells in a typical Western gut; these cells harbor ~300 mg of LPS, making it one of the highest-abundance molecules in the intestine. As a starting point for understanding the biological function of Bacteroides LPS, we have identified genes in Bacteroides thetaiotaomicron VPI 5482 involved in the biosynthesis of its lipid A core and glycan, generated mutants that elaborate altered forms of LPS, and used matrix-assisted laser desorption ionization–time of flight (MALDI-TOF) mass spectrometry to interrogate the molecular features of these variants. We demonstrate, inter alia, that the glycan does not appear to have a repeating unit, and so this strain produces lipooligosaccharide (LOS) rather than LPS. This result contrasts with Bacteroides vulgatus ATCC 8482, which by SDS-PAGE analysis appears to produce LPS with a repeating unit. Additionally, our identification of the B. thetaiotaomicron LOS oligosaccharide gene cluster allowed us to identify similar clusters in other Bacteroides species. Our work lays the foundation for developing a structure-function relationship for Bacteroides LPS/LOS in the context of host colonization. Much is known about the bacterial species and genes that make up the human microbiome, but remarkably little is known about the molecular mechanisms through which the microbiota influences host biology. A well-known mechanism by which bacteria influence the host centers around lipopolysaccharide (LPS), a component of the Gram-negative bacterial outer membrane. Pathogen-derived LPS is a potent ligand for host receptor Toll-like receptor 4, which plays an important role in sensing bacteria as part of the innate immune response. Puzzlingly, the most common genus of human gut bacteria, Bacteroides, produces LPS but does not elicit a potent proinflammatory response. Previous work showing that Bacteroides LPS differs structurally from pathogen-derived LPS suggested the outlines of an explanation. Here, we take the next step, elucidating the biosynthetic pathway for Bacteroides LPS and generating mutants in the process that will be of great use in understanding how this molecule modulates the host immune response.
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Di Lorenzo F, Palmigiano A, Duda KA, Pallach M, Busset N, Sturiale L, Giraud E, Garozzo D, Molinaro A, Silipo A. Structure of the Lipopolysaccharide from the Bradyrhizobium sp. ORS285 rfaL Mutant Strain. ChemistryOpen 2017; 6:541-553. [PMID: 28794950 PMCID: PMC5542761 DOI: 10.1002/open.201700074] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2017] [Indexed: 12/13/2022] Open
Abstract
The importance of the outer membrane and of its main constituent, lipopolysaccharide, in the symbiosis between rhizobia and leguminous host plants has been well studied. Here, the first complete structural characterization of the entire lipopolysaccharide from an O‐chain‐deficient Bradyrhizobium ORS285 rfaL mutant is achieved by a combination of chemical analysis, NMR spectroscopy, MALDI MS and MS/MS. The lipid A structure is shown to be consistent with previously reported Bradyrhizobium lipid A, that is, a heterogeneous blend of penta‐ to hepta‐acylated species carrying a nonstoichiometric hopanoid unit and possessing very‐long‐chain fatty acids ranging from 26:0(25‐OH) to 32:0(31‐OH). The structure of the core oligosaccharide region, fully characterized for the first time here, is revealed to be a nonphosphorylated linear chain with methylated sugar residues, with a heptose residue exclusively present in the outer core region, and with the presence of two singly substituted 3‐deoxy‐d‐manno‐oct‐2‐ulosonic acid (Kdo) residues, one of which is located in the outer core region. The lipid A moiety is linked to the core moiety through an uncommon 4‐substituted Kdo unit.
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Affiliation(s)
- Flaviana Di Lorenzo
- Department of Chemical Sciences University of Naples Federico II Via Cinthia 4 80126 Naples Italy
| | - Angelo Palmigiano
- CNR-Istituto per i Polimeri Compositi e Biomateriali IPCB-Unità di CataniaVia Gaifami 18 95126 Catania Italy
| | - Katarzyna A Duda
- Junior Group of Allergobiochemistry, Research Center Borstel, Leibniz Center for Medicine and Biosciences, Airway Research Center North (ARCN) German Center for Lung Research 23845 Borstel Germany
| | - Mateusz Pallach
- Department of Chemical Sciences University of Naples Federico II Via Cinthia 4 80126 Naples Italy
| | - Nicolas Busset
- IRD, Laboratoire des Symbioses Tropicales et Méditerranéennes UMR IRD/SupAgro/INRA/UM2/CIRAD, Campus International de Baillarguet, TA A-82/J34398 Montpellier Cedex 5 France
| | - Luisa Sturiale
- CNR-Istituto per i Polimeri Compositi e Biomateriali IPCB-Unità di CataniaVia Gaifami 18 95126 Catania Italy
| | - Eric Giraud
- IRD, Laboratoire des Symbioses Tropicales et Méditerranéennes UMR IRD/SupAgro/INRA/UM2/CIRAD, Campus International de Baillarguet, TA A-82/J34398 Montpellier Cedex 5 France
| | - Domenico Garozzo
- CNR-Istituto per i Polimeri Compositi e Biomateriali IPCB-Unità di CataniaVia Gaifami 18 95126 Catania Italy
| | - Antonio Molinaro
- 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
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Hassan AA, Maldonado RF, Dos Santos SC, Di Lorenzo F, Silipo A, Coutinho CP, Cooper VS, Molinaro A, Valvano MA, Sá-Correia I. Structure of O-Antigen and Hybrid Biosynthetic Locus in Burkholderia cenocepacia Clonal Variants Recovered from a Cystic Fibrosis Patient. Front Microbiol 2017. [PMID: 28642745 PMCID: PMC5462993 DOI: 10.3389/fmicb.2017.01027] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Burkholderia cenocepacia is an opportunistic pathogen associated with chronic lung infections and increased risk of death in patients with cystic fibrosis (CF). In this work, we investigated the lipopolysaccharide (LPS) of clinical variants of B. cenocepacia that were collected from a CF patient over a period of 3.5 years, from the onset of infection until death by necrotizing pneumonia (cepacia syndrome). We report the chemical structure of the LPS molecule of various sequential isolates and the identification of a novel hybrid O-antigen (OAg) biosynthetic cluster. The OAg repeating unit of the LPS from IST439, the initial isolate, is a [→2)-β-D-Ribf-(1→4)-α-D-GalpNAc-(1→] disaccharide, which was not previously described in B. cenocepacia. The IST439 OAg biosynthetic gene cluster contains 7 of 23 genes that are closely homologous to genes found in B. multivorans, another member of the Burkholderia cepacia complex. None of the subsequent isolates expressed OAg. Genomic sequencing of these isolates enabled the identification of mutations within the OAg cluster, but none of these mutations could be associated with the loss of OAg. This study provides support to the notion that OAg LPS modifications are an important factor in the adaptation of B. cenocepacia to chronic infection and that the heterogeneity of OAgs relates to variation within the OAg gene cluster, indicating that the gene cluster might have been assembled through multiple horizontal transmission events.
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Affiliation(s)
- A A Hassan
- Department of Bioengineering, Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de LisboaLisboa, Portugal
| | - Rita F Maldonado
- Department of Bioengineering, Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de LisboaLisboa, Portugal
| | - Sandra C Dos Santos
- Department of Bioengineering, Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de LisboaLisboa, Portugal
| | - Flaviana Di Lorenzo
- Department of Chemical Sciences, University of Napoli Federico II Complesso Universitário Monte SantangeloNapoli, Italy
| | - Alba Silipo
- Department of Chemical Sciences, University of Napoli Federico II Complesso Universitário Monte SantangeloNapoli, Italy
| | - Carla P Coutinho
- Department of Bioengineering, Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de LisboaLisboa, Portugal
| | - Vaughn S Cooper
- Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, PittsburghPA, United States
| | - Antonio Molinaro
- Department of Chemical Sciences, University of Napoli Federico II Complesso Universitário Monte SantangeloNapoli, Italy
| | - Miguel A Valvano
- The Wellcome-Wolfson Institute for Experimental Medicine, Queen's University BelfastBelfast, United Kingdom
| | - Isabel Sá-Correia
- Department of Bioengineering, Institute for Bioengineering and Biosciences, Instituto Superior Técnico, Universidade de LisboaLisboa, Portugal
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15
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Chemical Structure of the Lipid A component of Pseudomonas sp. strain PAMC 28618 from Thawing Permafrost in Relation to Pathogenicity. Sci Rep 2017; 7:2168. [PMID: 28526845 PMCID: PMC5438365 DOI: 10.1038/s41598-017-02145-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2016] [Accepted: 04/07/2017] [Indexed: 12/02/2022] Open
Abstract
Climate change causes permafrost thawing, and we are confronted with the unpredictable risk of newly discovered permafrost microbes that have disease-causing capabilities. Here, we first characterized the detailed chemical structure of the lipid A moiety from a Pseudomonas species that was isolated from thawing arctic permafrost using MALDI-based mass spectrometric approaches (i.e., MALDI-TOF MS and MALDI-QIT-TOF MSn). The MALDI multi-stage mass spectrometry (MS) analysis of lipid A extracted from the Pseudomonas sp. strain PAMC 28618 demonstrated that the hexaacyl lipid A ([M−H]− at m/z 1616.5) contains a glucosamine (GlcN) disaccharide backbone, two phosphates, four main acyl chains and two branched acyl chains. Moreover, the lipid A molecule–based structural activity relationship with other terrestrial Gram-negative bacteria indicated that strain PAMC 28618 has an identical lipid A structure with the mesophilic Pseudomonas cichorii which can cause rot disease in endive (Cichorium endivia) and that their bacterial toxicities were equivalent. Therefore, the overall lipid A validation process provides a general strategy for characterizing bacteria that have been isolated from arctic permafrost and analyzing their respective pathogenicities.
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16
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Di Lorenzo F, Silipo A, Andersen Gersby LB, Palmigiano A, Lanzetta R, Garozzo D, Boyer C, Pruvost O, Newman MA, Molinaro A. Xanthomonas citri pv. citri Pathotypes: LPS Structure and Function as Microbe-Associated Molecular Patterns. Chembiochem 2017; 18:772-781. [PMID: 28186388 DOI: 10.1002/cbic.201600671] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Indexed: 12/13/2022]
Abstract
Xanthomonas citri pv. citri is the pathogen responsible for Asiatic citrus canker, one of the most serious citrus diseases worldwide. The lipopolysaccharide (LPS) molecule has been demonstrated to be involved in X. citri pv. citri virulence. Despite enormous progress in investigations of the molecular mechanisms for bacterial pathogenicity, determination of the detailed LPS structure-activity relationship is limited, as the current knowledge is mainly based on structural determination of one X. citri pv. citri strain. As X. citri pv. citri strains are distinguished into three main pathogenicity groups, we characterized the full structure of the LPS from two pathotypes that differ in their host-range specificity. This revealed an intriguing difference in LPS O-chain structure. We also tested the LPSs and isolated lipid A moieties for their ability to act as microbe-associated molecular patterns in Arabidopsis thaliana. Both LPS/lipid As induced ROS accumulation, but no difference was observed between the two pathotypes.
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Affiliation(s)
- Flaviana Di Lorenzo
- 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
| | | | - Angelo Palmigiano
- CNR-Istituto per i Polimeri, Compositi e Biomateriali IPCB, via Gaifami 18, 95126, Catania, Italy
| | - Rosa Lanzetta
- Department of Chemical Sciences, University of Naples Federico II, via Cinthia 4, 80126, Naples, Italy
| | - Domenico Garozzo
- CNR-Istituto per i Polimeri, Compositi e Biomateriali IPCB, via Gaifami 18, 95126, Catania, Italy
| | - Claudine Boyer
- CIRAD, UMR Peuplements Végétaux et Bioagresseurs en Milieu Tropical (PVBMT), Saint Pierre, La Réunion, France
| | - Olivier Pruvost
- CIRAD, UMR Peuplements Végétaux et Bioagresseurs en Milieu Tropical (PVBMT), Saint Pierre, La Réunion, France
| | - Mari-Anne Newman
- Department of Plant and Environmental Sciences, University of Copenhagen, 1871, Frederiksberg, Copenhagen, Denmark
| | - Antonio Molinaro
- Department of Chemical Sciences, University of Naples Federico II, via Cinthia 4, 80126, Naples, Italy
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17
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Fathy Mohamed Y, Hamad M, Ortega XP, Valvano MA. The LpxL acyltransferase is required for normal growth and penta-acylation of lipid A in Burkholderia cenocepacia. Mol Microbiol 2017; 104:144-162. [PMID: 28085228 DOI: 10.1111/mmi.13618] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/10/2017] [Indexed: 12/27/2022]
Abstract
Lipid A anchors the lipopolysaccharide (LPS) to the outer membrane and is usually composed of a hexa-acylated diglucosamine backbone. Burkholderia cenocepacia, an opportunistic pathogen, produces a mixture of tetra- and penta-acylated lipid A. "Late" acyltransferases add secondary acyl chains to lipid A after the incorporation of four primary acyl chains to the diglucosamine backbone. Here, we report that B. cenocepacia has only one late acyltransferase, LpxL (BCAL0508), which adds a myristoyl chain to the 2' position of lipid A resulting in penta-acylated lipid A. We also identified PagL (BCAL0788), which acts as an outer membrane lipase by removing the primary β-hydroxymyristate (3-OH-C14:0) chain at the 3 position, leading to tetra-acylated lipid A. Unlike PagL, LpxL depletion caused reduced cell growth and defects in cell morphology, both of which were suppressed by overexpressing the LPS flippase MsbA (BCAL2408), suggesting that lipid A molecules lacking the fifth acyl chain contributed by LpxL are not good substrates for the flippase. We also show that intracellular B. cenocepacia within macrophages produced more penta-acylated lipid A, suggesting lipid A penta-acylation in B. cenocepacia is required not only for bacterial growth and morphology but also for adaptation to intracellular lifestyle.
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Affiliation(s)
- Yasmine Fathy Mohamed
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, BT9 7BL, UK.,Department of Microbiology and Immunology, Faculty of Pharmacy, Alexandria University, Alexandria, Egypt
| | - Mohamad Hamad
- Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada, N6A 5C1
| | - Ximena P Ortega
- Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada, N6A 5C1
| | - Miguel A Valvano
- Centre for Experimental Medicine, School of Medicine, Dentistry and Biomedical Sciences, Queen's University Belfast, Belfast, BT9 7BL, UK.,Department of Microbiology and Immunology, University of Western Ontario, London, ON, Canada, N6A 5C1
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18
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Kucharska I, Liang B, Ursini N, Tamm LK. Molecular Interactions of Lipopolysaccharide with an Outer Membrane Protein from Pseudomonas aeruginosa Probed by Solution NMR. Biochemistry 2016; 55:5061-72. [PMID: 27532487 DOI: 10.1021/acs.biochem.6b00630] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Pseudomonas aeruginosa is an opportunistic human pathogen causing pneumonias that are particularly severe in cystic fibrosis and immunocompromised patients. The outer membrane (OM) of P. aeruginosa is much less permeable to nutrients and other chemical compounds than that of Escherichia coli. The low permeability of the OM, which also contributes to Pseudomonas' significant antibiotic resistance, is augmented by the presence of the outer membrane protein H (OprH). OprH directly interacts with lipopolysaccharides (LPS) that constitute the outer leaflet of the OM and thus contributes to the structural stability of the OM. In this study, we used solution NMR spectroscopy to characterize the interactions between LPS and OprH in molecular detail. NMR chemical shift perturbations observed upon the addition of LPS to OprH in DHPC micelles indicate that this interaction is predominantly electrostatic and localized to the extracellular loops 2 and 3 and a number of highly conserved basic residues near the extracellular barrel rim of OprH. Single-site mutations of these residues were not enough to completely abolish binding, but OprH with cumulative mutations of Lys70, Arg72, and Lys103 no longer binds LPS. The dissociation constant (∼200 μM) measured by NMR is sufficient to efficiently bind LPS to OprH in the OM. This work highlights that solution NMR is suitable to study specific interactions of lipids with integral membrane proteins and provides a detailed molecular model for the interaction of LPS with OprH; i.e., an interaction that contributes to the integrity of the OM of P. aeruginosa under low divalent cation and antibiotic stress conditions. These methods should thus be useful for screening antibiotics that might disrupt OprH-LPS interactions and thereby increase the permeability of the OM of P. aeruginosa.
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Affiliation(s)
- Iga Kucharska
- Center for Membrane and Cell Physiology and Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine , Charlottesville, Virginia 22908, United States
| | - Binyong Liang
- Center for Membrane and Cell Physiology and Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine , Charlottesville, Virginia 22908, United States
| | - Nicholas Ursini
- Center for Membrane and Cell Physiology and Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine , Charlottesville, Virginia 22908, United States
| | - Lukas K Tamm
- Center for Membrane and Cell Physiology and Department of Molecular Physiology and Biological Physics, University of Virginia School of Medicine , Charlottesville, Virginia 22908, United States
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19
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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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20
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Di Lorenzo F, Silipo A, Matier T, Hanuszkiewicz A, Elborn JS, Lanzetta R, Sturiale L, Scamporrino A, Garozzo D, Valvano MA, Tunney MM, Molinaro A. Prevotella denticolaLipopolysaccharide from a Cystic Fibrosis Isolate Possesses a Unique Chemical Structure. European J Org Chem 2016. [DOI: 10.1002/ejoc.201600037] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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21
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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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22
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Larrouy-Maumus G, Clements A, Filloux A, McCarthy RR, Mostowy S. Direct detection of lipid A on intact Gram-negative bacteria by MALDI-TOF mass spectrometry. J Microbiol Methods 2016; 120:68-71. [PMID: 26656001 PMCID: PMC4717120 DOI: 10.1016/j.mimet.2015.12.004] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Revised: 12/02/2015] [Accepted: 12/02/2015] [Indexed: 11/29/2022]
Abstract
The purification and characterization of Gram-negative bacterial lipid A is tedious and time-consuming. Herein we report a rapid and sensitive method to identify lipid A directly on intact bacteria without any chemical treatment or purification, using an atypical solvent system to solubilize the matrix combined with MALDI-TOF mass spectrometry.
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Affiliation(s)
- Gerald Larrouy-Maumus
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, UK.
| | - Abigail Clements
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, UK
| | - Alain Filloux
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, UK
| | - Ronan R McCarthy
- MRC Centre for Molecular Bacteriology and Infection, Department of Life Sciences, Faculty of Natural Sciences, Imperial College London, London, UK
| | - Serge Mostowy
- MRC Centre for Molecular Bacteriology and Infection, Department of Medicine, Imperial College London, London, UK
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23
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Determination of the structure of the O-antigen and the lipid A from the entomopathogenic bacterium Pseudomonas entomophila lipopolysaccharide along with its immunological properties. Carbohydr Res 2015; 412:20-7. [DOI: 10.1016/j.carres.2015.04.017] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/11/2015] [Revised: 03/31/2015] [Accepted: 04/17/2015] [Indexed: 02/07/2023]
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24
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Kim JK, Son DW, Kim CH, Cho JH, Marchetti R, Silipo A, Sturiale L, Park HY, Huh YR, Nakayama H, Fukatsu T, Molinaro A, Lee BL. Insect Gut Symbiont Susceptibility to Host Antimicrobial Peptides Caused by Alteration of the Bacterial Cell Envelope. J Biol Chem 2015; 290:21042-21053. [PMID: 26116716 DOI: 10.1074/jbc.m115.651158] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2015] [Indexed: 01/05/2023] Open
Abstract
The molecular characterization of symbionts is pivotal for understanding the cross-talk between symbionts and hosts. In addition to valuable knowledge obtained from symbiont genomic studies, the biochemical characterization of symbionts is important to fully understand symbiotic interactions. The bean bug (Riptortus pedestris) has been recognized as a useful experimental insect gut symbiosis model system because of its cultivatable Burkholderia symbionts. This system is greatly advantageous because it allows the acquisition of a large quantity of homogeneous symbionts from the host midgut. Using these naïve gut symbionts, it is possible to directly compare in vivo symbiotic cells with in vitro cultured cells using biochemical approaches. With the goal of understanding molecular changes that occur in Burkholderia cells as they adapt to the Riptortus gut environment, we first elucidated that symbiotic Burkholderia cells are highly susceptible to purified Riptortus antimicrobial peptides. In search of the mechanisms of the increased immunosusceptibility of symbionts, we found striking differences in cell envelope structures between cultured and symbiotic Burkholderia cells. The bacterial lipopolysaccharide O antigen was absent from symbiotic cells examined by gel electrophoretic and mass spectrometric analyses, and their membranes were more sensitive to detergent lysis. These changes in the cell envelope were responsible for the increased susceptibility of the Burkholderia symbionts to host innate immunity. Our results suggest that the symbiotic interactions between the Riptortus host and Burkholderia gut symbionts induce bacterial cell envelope changes to achieve successful gut symbiosis.
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Affiliation(s)
- Jiyeun Kate Kim
- Global Research Laboratory, College of Pharmacy, Pusan National University, Pusan 609-735, South Korea
| | - Dae Woo Son
- Global Research Laboratory, College of Pharmacy, Pusan National University, Pusan 609-735, South Korea
| | - Chan-Hee Kim
- Global Research Laboratory, College of Pharmacy, Pusan National University, Pusan 609-735, South Korea
| | - Jae Hyun Cho
- Global Research Laboratory, College of Pharmacy, Pusan National University, Pusan 609-735, South Korea
| | - Roberta Marchetti
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, Napoli 80126, Italy
| | - Alba Silipo
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, Napoli 80126, Italy
| | - Luisa Sturiale
- CNR-Istituto per i Polimeri, Compositi e Biomateriali IPCB, Via P. Gaifami 18, Catania 95126, Italy
| | - Ha Young Park
- Global Research Laboratory, College of Pharmacy, Pusan National University, Pusan 609-735, South Korea
| | - Ye Rang Huh
- Global Research Laboratory, College of Pharmacy, Pusan National University, Pusan 609-735, South Korea
| | - Hiroshi Nakayama
- Biomolecular Characterization Team, RIKEN Advanced Science Institute, Saitama 351-0198, Japan
| | - Takema Fukatsu
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8566, Japan
| | - Antonio Molinaro
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, Napoli 80126, Italy
| | - Bok Luel Lee
- Global Research Laboratory, College of Pharmacy, Pusan National University, Pusan 609-735, South Korea.
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25
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O'Brien JP, Needham BD, Brown DB, Trent MS, Brodbelt JS. Top-Down Strategies for the Structural Elucidation of Intact Gram-negative Bacterial Endotoxins. Chem Sci 2014; 5:4291-4301. [PMID: 25386333 PMCID: PMC4224326 DOI: 10.1039/c4sc01034e] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Re-modelling of lipopolysaccharides, which are the primary constituent of the outer cell membrane of Gram-negative bacteria, modulates pathogenesis and resistance to microbials. Reported herein is the characterization of intact Gram-negative bacterial lipooligosaccharides (LOS) via a new strategy utilizing online liquid chromatography (LC) coupled with ultraviolet photodissociation (UVPD) mass spectrometry. Compared to collision-based MS/MS methods, UVPD and UVPD/HCD promoted a greater array of cleavages within both the glycan and lipid moieties, including C-C, C-N, C-O cleavages in the acyl chains as well as glycosidic and cross-ring cleavages, thus providing the most far-reaching structural characterization of LOS. This LC-MS/MS strategy affords a robust analytical method to structurally characterize complex mixtures of bacterial endotoxins that maintains the integrity of the core oligosaccharide and lipid A domains of LOS, providing direct feedback about the cell envelope architectures and LOS modification strategies involved in resistance host innate immune defense.
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Affiliation(s)
- John P O'Brien
- Department of Chemistry, The University of Texas at Austin, 1 University Station A5300, Austin, TX, USA 78712
| | - Brittany D Needham
- The University of Texas at Austin, Department of Molecular Biosciences, 2506 Speedway A5000, Austin, TX, USA 78712
| | - Dusty B Brown
- The University of Texas at Austin, Department of Molecular Biosciences, 2506 Speedway A5000, Austin, TX, USA 78712
| | - M Stephen Trent
- The University of Texas at Austin, Department of Molecular Biosciences, 2506 Speedway A5000, Austin, TX, USA 78712
| | - Jennifer S Brodbelt
- Department of Chemistry, The University of Texas at Austin, 1 University Station A5300, Austin, TX, USA 78712
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26
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Molinaro A, Holst O, Di Lorenzo F, Callaghan M, Nurisso A, D'Errico G, Zamyatina A, Peri F, Berisio R, Jerala R, Jiménez-Barbero J, Silipo A, Martín-Santamaría S. Chemistry of lipid A: at the heart of innate immunity. Chemistry 2014; 21:500-19. [PMID: 25353096 DOI: 10.1002/chem.201403923] [Citation(s) in RCA: 162] [Impact Index Per Article: 16.2] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
In many Gram-negative bacteria, lipopolysaccharide (LPS) and its lipid A moiety are pivotal for bacterial survival. Depending on its structure, lipid A carries the toxic properties of the LPS and acts as a potent elicitor of the host innate immune system via the Toll-like receptor 4/myeloid differentiation factor 2 (TLR4/MD-2) receptor complex. It often causes a wide variety of biological effects ranging from a remarkable enhancement of the resistance to the infection to an uncontrolled and massive immune response resulting in sepsis and septic shock. Since the bioactivity of lipid A is strongly influenced by its primary structure, a broad range of chemical syntheses of lipid A derivatives have made an enormous contribution to the characterization of lipid A bioactivity, providing novel pharmacological targets for the development of new biomedical therapies. Here, we describe and discuss the chemical aspects regarding lipid A and its role in innate immunity, from the (bio)synthesis, isolation and characterization to the molecular recognition at the atomic level.
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Affiliation(s)
- Antonio Molinaro
- Department of Chemical Sciences, University of Naples Federico II via Cinthia 4, 80126 Napoli (Italy).
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27
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Di Lorenzo F, Paciello I, Fazio LL, Albuquerque L, Sturiale L, da Costa MS, Lanzetta R, Parrilli M, Garozzo D, Bernardini ML, Silipo DA, Molinaro A. Thermophiles as potential source of novel endotoxin antagonists: the full structure and bioactivity of the lipo-oligosaccharide from Thermomonas hydrothermalis. Chembiochem 2014; 15:2146-55. [PMID: 25171597 DOI: 10.1002/cbic.201402233] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/16/2014] [Indexed: 01/10/2023]
Abstract
Thermomonas hydrothermalis is a Gram-negative thermophilic bacterium that is able to live at 50 °C. This ability is attributed to chemical modifications, involving those to bacterial cell-wall components, such as proteins and (glyco)lipids. As the main component of the outer membrane of Gram-negative bacteria, lipopolysaccharides (LPSs) are exposed to the environment, thus they can undergo structural chemical changes to allow thermophilic bacteria to live at their optimal growth temperature. Furthermore, as one of the major target of the eukaryotic innate immune system, LPS elicits host immune response in a structure-dependent mode; thus the uncommon chemical features of thermophilic bacterial LPSs might exert a different biological action on the innate immune system-an antagonistic effect, as shown in studies of LPS structure-activity relationship in the ongoing research into antagonist LPS candidates. Here, we report the complete structural and biological activity analysis of the lipo-oligosaccharide isolated from Thermomonas hydrothermalis, achieved by a multidisciplinary approach (chemical analysis, NMR, MALDI MS and cellular immunology). We demonstrate a tricky and interesting structure combined with a very interesting effect on human innate immunity.
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Affiliation(s)
- Flaviana Di Lorenzo
- Dipartimento di Scienze Chimiche, Università di Napoli "Federico II", Complesso Universitario Monte S.Angelo, Via Cintia 4, 80126 Napoli (Italy)
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Lorenzo FD, Sturiale L, Palmigiano A, Fazio LL, Paciello I, Coutinho CP, Sá-Correia I, Bernardini M, Lanzetta R, Garozzo D, Silipo A, Molinaro A. Chemistry and Biology of the Potent Endotoxin from aBurkholderia dolosaClinical Isolate from a Cystic Fibrosis Patient. Chembiochem 2013; 14:1105-15. [DOI: 10.1002/cbic.201300062] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2013] [Indexed: 01/10/2023]
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Silipo A, Di Lorenzo F, Fazio LL, Paciello I, Sturiale L, Palmigiano A, Parrilli M, Grant WD, Garozzo D, Lanzetta R, Bernardini ML, Molinaro A. Structure and Immunological Activity of the Lipopolysaccharide Isolated from the SpeciesAlkalimonas delamerensis. European J Org Chem 2013. [DOI: 10.1002/ejoc.201201702] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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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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John CM, Liu M, Phillips NJ, Yang Z, Funk CR, Zimmerman LI, Griffiss JM, Stein DC, Jarvis GA. Lack of lipid A pyrophosphorylation and functional lptA reduces inflammation by Neisseria commensals. Infect Immun 2012; 80:4014-26. [PMID: 22949553 PMCID: PMC3486066 DOI: 10.1128/iai.00506-12] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Accepted: 08/29/2012] [Indexed: 11/20/2022] Open
Abstract
The interaction of the immune system with Neisseria commensals remains poorly understood. We have previously shown that phosphoethanolamine on the lipid A portion of lipooligosaccharide (LOS) plays an important role in Toll-like receptor 4 (TLR4) signaling. For pathogenic Neisseria, phosphoethanolamine is added to lipid A by the phosphoethanolamine transferase specific for lipid A, which is encoded by lptA. Here, we report that Southern hybridizations and bioinformatics analyses of genomic sequences from all eight commensal Neisseria species confirmed that lptA was absent in 15 of 17 strains examined but was present in N. lactamica. Mass spectrometry of lipid A and intact LOS revealed the lack of both pyrophosphorylation and phosphoethanolaminylation in lipid A of commensal species lacking lptA. Inflammatory signaling in human THP-1 monocytic cells was much greater with pathogenic than with commensal Neisseria strains that lacked lptA, and greater sensitivity to polymyxin B was consistent with the absence of phosphoethanolamine. Unlike the other commensals, whole bacteria of two N. lactamica commensal strains had low inflammatory potential, whereas their lipid A had high-level pyrophosphorylation and phosphoethanolaminylation and induced high-level inflammatory signaling, supporting previous studies indicating that this species uses mechanisms other than altering lipid A to support commensalism. A meningococcal lptA deletion mutant had reduced inflammatory potential, further illustrating the importance of lipid A pyrophosphorylation and phosphoethanolaminylation in the bioactivity of LOS. Overall, our results indicate that lack of pyrophosphorylation and phosphoethanolaminylation of lipid A contributes to the immune privilege of most commensal Neisseria strains by reducing the inflammatory potential of LOS.
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Affiliation(s)
- Constance M. John
- Center for Immunochemistry, Veterans Affairs Medical Center, San Francisco, California, USA
| | - Mingfeng Liu
- Center for Immunochemistry, Veterans Affairs Medical Center, San Francisco, California, USA
- Department of Laboratory Medicine
| | - Nancy J. Phillips
- Department of Pharmaceutical Chemistry, University of California, San Francisco, California, USA
| | - Zhijie Yang
- Center for Immunochemistry, Veterans Affairs Medical Center, San Francisco, California, USA
| | - Courtney R. Funk
- Center for Immunochemistry, Veterans Affairs Medical Center, San Francisco, California, USA
| | - Lindsey I. Zimmerman
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA
| | - J. McLeod Griffiss
- Center for Immunochemistry, Veterans Affairs Medical Center, San Francisco, California, USA
- Department of Laboratory Medicine
| | - Daniel C. Stein
- Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, Maryland, USA
| | - Gary A. Jarvis
- Center for Immunochemistry, Veterans Affairs Medical Center, San Francisco, California, USA
- Department of Laboratory Medicine
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Hamad MA, Di Lorenzo F, Molinaro A, Valvano MA. Aminoarabinose is essential for lipopolysaccharide export and intrinsic antimicrobial peptide resistance inBurkholderia cenocepacia†. Mol Microbiol 2012; 85:962-74. [DOI: 10.1111/j.1365-2958.2012.08154.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
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Hung WT, Wang SH, Chen YT, Yu HM, Chen CH, Yang WB. MALDI-TOF MS analysis of native and permethylated or benzimidazole-derivatized polysaccharides. Molecules 2012; 17:4950-61. [PMID: 22547317 PMCID: PMC6268202 DOI: 10.3390/molecules17054950] [Citation(s) in RCA: 33] [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: 12/20/2011] [Revised: 04/06/2012] [Accepted: 04/20/2012] [Indexed: 12/16/2022] Open
Abstract
MALDI-TOF MS provides rapid and sensitive analyses of larger biomolecules. However, MS analyses of polysaccharide have been reported to have lower sensitivity compared to peptides and proteins. Here, we investigated some polysaccharides chemically derivatized by permethylation and ortho-phenylene diamine (OPD) tagging. Methylated glycan is obviously able to improve the sensitivity for mass spectrometry detection. Oxidative condensation by UV-activation tagging to saccharides by OPD and peptide-OPD also improve the sensitivity of MALDI-TOF MS analyses. Polysaccharides including dextran, glucomannan, arabinoxylan, arabinogalactan and beta-1,3-glucan, isolated from nutritional supplements of Ganoderma lucidum and Saccharomyces pastorianus were measured using MALDI-TOF MS with 2,5-dihydroxybenzoic acid (2,5-DHB) as the matrix. These glycans were also derivatized to methylated and benzimidazole-tagged glycans by chemical transformation for molecular weight analysis. The derivatized polysaccharides showed excellent MALDI-TOF MS signal enhancement in the molecular weight range from 1 to 5 kDa. Here, we demonstrate an efficient method to give glycan-benzimidazole (glycan-BIM) derivatives for polysaccharide determination in MALDI-TOF MS. Therefore, permethylated or benzimidazole-derivatized polysaccharides provide a new option for polysaccharide analysis using MALDI-TOF MS.
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Affiliation(s)
- Wei-Ting Hung
- Genomics Research Center, Academia Sinica, 128, Academia Road Sec. 2, Taipei 115, Taiwan
| | - Shwu-Huey Wang
- Core Facility Center, Office of Research and Development, Taipei Medical University, 250 Wu-Hsing Street, Taipei 110, Taiwan
| | - Yi-Ting Chen
- Genomics Research Center, Academia Sinica, 128, Academia Road Sec. 2, Taipei 115, Taiwan
| | - Hui-Ming Yu
- Genomics Research Center, Academia Sinica, 128, Academia Road Sec. 2, Taipei 115, Taiwan
| | - Chung-Hsuan Chen
- Genomics Research Center, Academia Sinica, 128, Academia Road Sec. 2, Taipei 115, Taiwan
| | - Wen-Bin Yang
- Genomics Research Center, Academia Sinica, 128, Academia Road Sec. 2, Taipei 115, Taiwan
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Sturiale L, Palmigiano A, Silipo A, Knirel YA, Anisimov AP, Lanzetta R, Parrilli M, Molinaro A, Garozzo D. Reflectron MALDI TOF and MALDI TOF/TOF mass spectrometry reveal novel structural details of native lipooligosaccharides. JOURNAL OF MASS SPECTROMETRY : JMS 2011; 46:1135-1142. [PMID: 22124985 DOI: 10.1002/jms.2000] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Lipooligosaccharides (LOS) are powerful Gram-negative glycolipids that evade the immune system and invade host animal and vegetal cells. The structural elucidation of LOS is pivotal to understanding the mechanisms of infection at the molecular level. The amphiphilic nature of LOS has been the main obstacle for structural analysis by matrix-assisted laser desorption/ionization (MALDI) mass spectrometry (MS). Our approach has resolved this important issue and has permitted us to obtain reflectron MALDI mass spectra of LOS to reveal the fine chemical structure with minimal structural variations. The high-quality MALDI mass spectra show LOS species characteristic of molecular ions and defined fragments due to decay in the ion source. The in-source decay yields B-type ions, which correspond to core oligosaccharide(s), and Y-type ions, which are related to lipid A unit(s). MALDI tandem time-of-flight (TOF/TOF) MS of lipid A allowed for the elucidation of its structure directly from purified intact LOS without the need for any chemical manipulations. These findings constitute a significant advancement in the analysis of such an important biomolecule by MALDI MS.
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Affiliation(s)
- Luisa Sturiale
- CNR Istituto per la Chimica e la Tecnologia dei Polimeri, Via P. Gaifami 18, 95126 Catania, Italy
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Harvey DJ. Analysis of carbohydrates and glycoconjugates by matrix-assisted laser desorption/ionization mass spectrometry: an update for the period 2005-2006. MASS SPECTROMETRY REVIEWS 2011; 30:1-100. [PMID: 20222147 DOI: 10.1002/mas.20265] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
This review is the fourth update of the original review, 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 2006. The review covers fundamental studies, fragmentation of carbohydrate ions, method developments, and applications of the technique to the analysis of different types of carbohydrate. Specific compound classes that are covered include carbohydrate polymers from plants, N- and O-linked glycans from glycoproteins, glycated proteins, glycolipids from bacteria, glycosides, and various other natural products. There is a short section on the use of MALDI-TOF mass spectrometry for the study of enzymes involved in glycan processing, a section on industrial processes, particularly the development of biopharmaceuticals and a section on the use of MALDI-MS to monitor products of chemical synthesis of carbohydrates. Large carbohydrate-protein complexes and glycodendrimers are highlighted in this final section.
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Affiliation(s)
- David J Harvey
- Department of Biochemistry, Oxford Glycobiology Institute, University of Oxford, Oxford OX1 3QU, UK.
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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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Liu M, John CM, Jarvis GA. Phosphoryl moieties of lipid A from Neisseria meningitidis and N. gonorrhoeae lipooligosaccharides play an important role in activation of both MyD88- and TRIF-dependent TLR4-MD-2 signaling pathways. THE JOURNAL OF IMMUNOLOGY 2010; 185:6974-84. [PMID: 21037101 DOI: 10.4049/jimmunol.1000953] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
We have previously shown that the lipooligosaccharide (LOS) from Neisseria meningitidis and N. gonorrhoeae engages the TLR4-MD-2 complex. In this study, we report that LOS from different meningococcal and gonococcal strains have different potencies to activate NF-κB through TLR4-MD-2 and that the relative activation can be correlated with ion abundances in MALDI-TOF mass spectrometry that are indicative of the number of phosphoryl substituents on the lipid A (LA) component of the LOS. The LOSs from three of the strains, meningococcal strain 89I and gonococcal strains 1291 and GC56, representing high, intermediate, and low potency on NF-κB activation, respectively, differently activated cytokine expression through the TLR4-MD-2 pathway in monocytes. In addition to induction of typical inflammatory cytokines such as TNF-α, IL-1β, and IL-6, MIP-1α and MIP-1β also were significantly higher in cells treated with 89I LOS, which had the most phosphoryl substitutions on the LA compared with 1291 LOS and GC56 LOS. We found that LOS activated both the MyD88- and TRIF-dependent pathways through NF-κB and IFN regulatory factor 3 transcription factors, respectively. Moreover, LOS induced the expression of costimulatory molecule CD80 on the surfaces of monocytes via upregulation of IFN regulatory factor 1. These results suggest that phosphoryl moieties of LA from N. meningitidis and N. gonorrhoeae LOSs play an important role in activation of both the MyD88- and TRIF-dependent pathways. Our findings are consistent with the concept that bacteria modulate pathogen-associated molecular patterns by expression of phosphoryl moieties on the LA to optimize interactions with the host.
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Affiliation(s)
- Mingfeng Liu
- Center for Immunochemistry, Veterans Affairs Medical Center, San Francisco, CA, 94121, USA
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Structural Elucidation of a NovelB. cenocepaciaET-12 Lipooligosaccharide Isolated from a Cystic Fibrosis Patient after Lung Transplantation. European J Org Chem 2010. [DOI: 10.1002/ejoc.200901200] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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39
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Ierano T, Silipo A, Sturiale L, Garozzo D, Bryant C, Lanzetta R, Parrilli M, Aldridge C, Gould FK, Corris PA, Khan CMA, De Soyza A, Molinaro A. First structural characterization of Burkholderia vietnamiensis lipooligosaccharide from cystic fibrosis-associated lung transplantation strains. Glycobiology 2009; 19:1214-23. [DOI: 10.1093/glycob/cwp112] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
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John CM, Liu M, Jarvis GA. Natural phosphoryl and acyl variants of lipid A from Neisseria meningitidis strain 89I differentially induce tumor necrosis factor-alpha in human monocytes. J Biol Chem 2009; 284:21515-25. [PMID: 19531474 DOI: 10.1074/jbc.m109.004887] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The native lipooligosaccharide (LOS) from Neisseria meningitidis strain 89I was analyzed by matrix-assisted laser desorption ionization (MALDI) time-of-flight (TOF) mass spectrometry and the spectrum compared with that of the LOS after O-deacylation and hydrogen fluoride treatment. The data are consistent with the presence of natural variations in the LOS, which include a triphosphorylated lipid A (LA) with and without a phosphoethanolamine group, and both hexa- and pentaacylated LA molecules. Thin-layer chromatography was performed on 89I LA produced by hydrolysis of the LOS, and the purified LA molecules were analyzed by MALDI-TOF and tested for their relative ability to induce the secretion of tumor necrosis factor-alpha by human monocytic THP-1 cells and primary human monocytes. The potency of tumor necrosis factor-alpha induction varied by approximately 2-10-fold, depending on the state of acylation and phosphorylation. The results highlight the significance of phosphorylation along with acylation of the LA component of LOS in stimulation of inflammatory signaling, and suggest that natural strain variation in these moieties may be a feature of meningococcal bacteria, which is of critical importance to the progression of the infection.
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Affiliation(s)
- Constance M John
- Center for Immunochemistry, Veterans Affairs Medical Center, San Francisco, California 94121, USA
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41
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John CM, Liu M, Jarvis GA. Profiles of structural heterogeneity in native lipooligosaccharides of Neisseria and cytokine induction. J Lipid Res 2008; 50:424-438. [PMID: 18832773 DOI: 10.1194/jlr.m800184-jlr200] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Fine differences in the phosphorylation and acylation of lipooligosaccharide (LOS) from Neisseria species are thought to profoundly influence the virulence of the organisms and the innate immune responses of the host, such as signaling through toll-like receptor 4 (TLR4) and triggering receptor expressed on myeloid cells (TREM). MALDI time-of-flight (TOF) mass spectrometry was used to characterize heterogeneity in the native LOS from Neisseria gonorrheae and N. meningitidis. A sample preparation methodology previously reported for Escherichia coli lipopolysaccharide (LPS) employing deposition of untreated LOS on a thin layer of a film composed of 2,4,6-trihydroxyacetophenone and nitrocellulose was used. Prominent peaks were observed corresponding to molecular ions and to fragment ions primarily formed by cleavage between the 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo) and the lipid A (LA). Analyses of these data and comparison with spectra of the corresponding O-deacylated or hydrogen fluoride-treated LOS enabled the detection of novel species that apparently differed by the expression of up to three phosphates with one or more phosphoethanolamine (PEA) groups on the LA. We found that the heterogeneity profile of acylation and phosphorylation correlates with the induction of proinflammatory cytokines in THP-1 monocytic cells. This methodology enabled us to rapidly profile components of structural variants of native LOS that are of importance biologically.
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Affiliation(s)
- Constance M John
- Center for Immunochemistry, Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA, 94121
| | - Mingfeng Liu
- Center for Immunochemistry, Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA, 94121
| | - Gary A Jarvis
- Center for Immunochemistry, Veterans Affairs Medical Center, 4150 Clement Street, San Francisco, CA, 94121; Department of Laboratory Medicine, University of California, San Francisco, CA 94143.
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42
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Ieranò T, Silipo A, Sturiale L, Garozzo D, Brookes H, Khan CMA, Bryant C, Gould FK, Corris PA, Lanzetta R, Parrilli M, De Soyza A, Molinaro A. The structure and proinflammatory activity of the lipopolysaccharide from Burkholderia multivorans and the differences between clonal strains colonizing pre and posttransplanted lungs. Glycobiology 2008; 18:871-81. [DOI: 10.1093/glycob/cwn074] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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43
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Gargiulo V, Garozzo D, Lanzetta R, Molinaro A, Sturiale L, De Castro C, Parrilli M. Rhizobium rubiT: A Gram‐Negative Phytopathogenic Bacterium Expressing the Lewis B Epitope on the Outer Core of its Lipooligosaccharide Fraction. Chembiochem 2008; 9:1830-5. [DOI: 10.1002/cbic.200800191] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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44
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Silipo A, Sturiale L, Garozzo D, Erbs G, Jensen TT, Lanzetta R, Dow JM, Parrilli M, Newman MA, Molinaro A. The Acylation and Phosphorylation Pattern of Lipid A fromXanthomonas Campestris Strongly Influence its Ability to Trigger the Innate Immune Response in Arabidopsis. Chembiochem 2008; 9:896-904. [DOI: 10.1002/cbic.200700693] [Citation(s) in RCA: 52] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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45
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Leone S, Lanzetta R, Scognamiglio R, Alfieri F, Izzo V, Di Donato A, Parrilli M, Holst O, Molinaro A. The structure of the O-specific polysaccharide from the lipopolysaccharide of Pseudomonas sp. OX1 cultivated in the presence of the azo dye Orange II. Carbohydr Res 2008; 343:674-84. [DOI: 10.1016/j.carres.2008.01.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2007] [Revised: 01/07/2008] [Accepted: 01/14/2008] [Indexed: 11/26/2022]
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46
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Molinaro A, Silipo A, Castro CD, Sturiale L, Nigro G, Garozzo D, Bernardini ML, Lanzetta R, Parrilli M. Full structural characterization of Shigella flexneri M90T serotype 5 wild-type R-LPS and its delta galU mutant: glycine residue location in the inner core of the lipopolysaccharide. Glycobiology 2008; 18:260-9. [PMID: 18174310 DOI: 10.1093/glycob/cwm140] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Shigella flexneri is a gram-negative bacterium responsible for serious enteric infections that occur mainly in the terminal ileum and colon. High interest in Shigella, as a human pathogen, is driven by its antibiotic resistance and the necessity to develop a vaccine against its infections. Vaccines of the last generation use carbohydrate moieties of the lipopolysaccharide as probable candidates. For this reason, the primary structure of the core oligosaccharide from the R-LPS produced by S. flexneri M90T serotype 5 using chemical analysis, nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry (MALDI), is herein reported. This is the first time that the core oligosaccharide primary structure by S. flexneri M90T is established in an unambiguous multidisciplinary approach. Chemical and spectroscopical investigation of the de-acetylated LPS showed that the inner core structure is characterized by a L,D-Hep-(1 -->7)-L,D-Hep-(1 -->3)-L,D-Hep-(1 -->5)-[Kdo-(2 -->4)]-Kdo sequence that is the common structural theme identified in Enterobacteriaceae. In particular, in S. flexneri M90T serotype 5 LPS, a glucosamine residue is additionally sitting at O-7 of the last heptose whereas the outer core is characterized by glucose and galactose residues. Also, in order to exactly define the position of glycine that is an integral constituent of the core region of the LPS, we created a S. flexneri M90T delta galU mutant and studied its LOS. In this way it was possible to establish that glycine is sitting at O-6 of the second heptose in the inner core.
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Affiliation(s)
- Antonio Molinaro
- Dipartimento di Chimica Organica e Biochimica, Università degli Studi di Napoli Federico II, Via Cintia 4, I-80126 Napoli, Italy.
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Li J, Ryder C, Mandal M, Ahmed F, Azadi P, Snyder DS, Pechous RD, Zahrt T, Inzana TJ. Attenuation and protective efficacy of an O-antigen-deficient mutant of Francisella tularensis LVS. MICROBIOLOGY-SGM 2007; 153:3141-3153. [PMID: 17768257 DOI: 10.1099/mic.0.2007/006460-0] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Francisella tularensis is a zoonotic, Gram-negative coccobacillus that causes tularemia in humans and animals. F. tularensis subspecies tularensis (type A) and F. tularensis subspecies holarctica (type B) are antigenically similar and more virulent than Francisella novicida in humans. The genetic locus that encodes the LPS O antigen was found to be substantially different between the type B live vaccine strain (LVS) and F. novicida. One LVS-specific gene with homology to a galactosyl transferase was selected for allelic replacement using a sacB-chloramphenicol expression suicide plasmid, and recombinants were screened for colony morphology on Congo red agar that matched that of F. novicida. Two mutants (WbtI(S187Y) and WbtI(G191V)) were isolated that contained substitutions in conserved motifs in the sugar transamine/perosamine synthetase (WbtI) of the O-antigen locus, and the latter mutant was extensively tested and characterized. WbtI(G191V) grew at the same rate as the parent strain in Chamberlain's defined medium, completely lacked O antigen, was serum-sensitive but could grow in a mouse macrophage cell line, had increased resistance to sodium deoxycholate, and was highly attenuated in mice. Complementation of WbtI(G191V) with the wild-type wbtI gene in trans restored normal LPS synthesis, phenotypic properties similar to the parent, and virulence in mice. Immunization with WbtI(G191V) protected mice against a relatively low-dose intraperitoneal challenge with LVS, but was less protective against a high-dose challenge. These results indicate that complete loss of O antigen alters the surface phenotype and abrogates virulence in F. tularensis, but also compromises the induction of full protective immunity against F. tularensis infection in mice.
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Affiliation(s)
- Jiaxin Li
- Center for Molecular Medicine and Infectious Diseases, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Cheryl Ryder
- Center for Molecular Medicine and Infectious Diseases, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Manas Mandal
- Center for Molecular Medicine and Infectious Diseases, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Farzana Ahmed
- Center for Molecular Medicine and Infectious Diseases, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
| | - Parastoo Azadi
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - D Scott Snyder
- Complex Carbohydrate Research Center, University of Georgia, Athens, GA, USA
| | - Roger D Pechous
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Thomas Zahrt
- Department of Microbiology and Molecular Genetics, Medical College of Wisconsin, Milwaukee, WI, USA
| | - Thomas J Inzana
- Center for Molecular Medicine and Infectious Diseases, Virginia-Maryland Regional College of Veterinary Medicine, Virginia Polytechnic Institute and State University, Blacksburg, VA, USA
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48
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Silipo A, Molinaro A, Ieranò T, De Soyza A, Sturiale L, Garozzo D, Aldridge C, Corris PA, Khan CMA, Lanzetta R, Parrilli M. The complete structure and pro-inflammatory activity of the lipooligosaccharide of the highly epidemic and virulent gram-negative bacterium Burkholderia cenocepacia ET-12 (strain J2315). Chemistry 2007; 13:3501-11. [PMID: 17219455 DOI: 10.1002/chem.200601406] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Members of genus Burkholderia include opportunistic Gram-negative bacteria that are responsible for serious infections in immunocompromised and cystic fibrosis (CF) patients. The Burkholderia cepacia complex is a group of microorganisms composed of at least nine closely related genomovars. Among these, B. cenocepacia is widely recognized to cause epidemics associated with excessive mortality. Species that belong to this strain are problematic CF pathogens because of their high resistance to antibiotics, which makes respiratory infections difficult to treat and impossible to eradicate. Infection by these bacteria is associated with higher mortality in CF and poor outcomes following lung transplantation. One virulence factor contributing to this is the pro-inflammatory lipopolysaccharide (LPS) molecules. Thus, the knowledge of the lipopolysaccharide structure is an essential prerequisite to the understanding of the molecular mechanisms involved in the inflammatory process. Such data are instrumental in aiding the design of antimicrobial compounds and for developing therapeutic strategies against the inflammatory cascade. In particular, defining the structure of the LPS from B. cenocepacia ET-12 clone LMG 16656 (also known as J2315) is extremely important given the recent completion of the sequencing project at the Sanger Centre using this specific strain. In this paper we address this issue by defining the pro-inflammatory activity of the pure lipopolysaccharide, and by describing its full primary structure. The activity of the lipopolysaccharide was tested as a stimulant in human myelomonocytic U937 cells. The structural analysis was carried out by compositional analysis, mass spectrometry and 2D NMR spectroscopy on the intact lipooligosacchride (LOS) and its fragments, which were obtained by selective chemical degradations.
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Affiliation(s)
- Alba Silipo
- Dipartimento di Chimica Organica e Biochimica, Università di Napoli, Complesso Universitario Monte Sant'angelo, Via Cintia 4, 80126 Napoli, Italy
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49
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Leone S, Molinaro A, Sturiale L, Garozzo D, Nazarenko EL, Gorshkova RP, Ivanova EP, Shevchenko LS, Lanzetta R, Parrilli M. The Outer Membrane of the Marine Gram-Negative BacteriumAlteromonas addita is Composed of a Very Short-Chain Lipopolysaccharide with a High Negative Charge Density. European J Org Chem 2007. [DOI: 10.1002/ejoc.200600906] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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50
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Silipo A, Molinaro A, Comegna D, Sturiale L, Cescutti P, Garozzo D, Lanzetta R, Parrilli M. Full Structural Characterisation of the Lipooligosaccharide of aBurkholderiapyrrocinia Clinical Isolate. European J Org Chem 2006. [DOI: 10.1002/ejoc.200600520] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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