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Dardelle F, Phelip C, Darabi M, Kondakova T, Warnet X, Combret E, Juranville E, Novikov A, Kerzerho J, Caroff M. Diversity, Complexity, and Specificity of Bacterial Lipopolysaccharide (LPS) Structures Impacting Their Detection and Quantification. Int J Mol Sci 2024; 25:3927. [PMID: 38612737 PMCID: PMC11011966 DOI: 10.3390/ijms25073927] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 03/21/2024] [Accepted: 03/23/2024] [Indexed: 04/14/2024] Open
Abstract
Endotoxins are toxic lipopolysaccharides (LPSs), extending from the outer membrane of Gram-negative bacteria and notorious for their toxicity and deleterious effects. The comparison of different LPSs, isolated from various Gram-negative bacteria, shows a global similar architecture corresponding to a glycolipid lipid A moiety, a core oligosaccharide, and outermost long O-chain polysaccharides with molecular weights from 2 to 20 kDa. LPSs display high diversity and specificity among genera and species, and each bacterium contains a unique set of LPS structures, constituting its protective external barrier. Some LPSs are not toxic due to their particular structures. Different, well-characterized, and highly purified LPSs were used in this work to determine endotoxin detection rules and identify their impact on the host. Endotoxin detection is a major task to ensure the safety of human health, especially in the pharma and food sectors. Here, we describe the impact of different LPS structures obtained under different bacterial growth conditions on selective LPS detection methods such as LAL, HEK-blue TLR-4, LC-MS2, and MALDI-MS. In these various assays, LPSs were shown to respond differently, mainly attributable to their lipid A structures, their fatty acid numbers and chain lengths, the presence of phosphate groups, and their possible substitutions.
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Affiliation(s)
- Flavien Dardelle
- LPS-BioSciences, Bâtiment 440, Université de Paris-Saclay, 91400 Orsay, France; (F.D.); (M.D.); (E.J.)
| | - Capucine Phelip
- HEPHAISTOS-Pharma, Bâtiment 440, Université de Paris-Saclay, 91400 Orsay, France; (C.P.); (A.N.); (J.K.)
| | - Maryam Darabi
- LPS-BioSciences, Bâtiment 440, Université de Paris-Saclay, 91400 Orsay, France; (F.D.); (M.D.); (E.J.)
| | - Tatiana Kondakova
- LPS-BioSciences, Bâtiment 440, Université de Paris-Saclay, 91400 Orsay, France; (F.D.); (M.D.); (E.J.)
| | - Xavier Warnet
- LPS-BioSciences, Bâtiment 440, Université de Paris-Saclay, 91400 Orsay, France; (F.D.); (M.D.); (E.J.)
| | - Edyta Combret
- LPS-BioSciences, Bâtiment 440, Université de Paris-Saclay, 91400 Orsay, France; (F.D.); (M.D.); (E.J.)
| | - Eugenie Juranville
- LPS-BioSciences, Bâtiment 440, Université de Paris-Saclay, 91400 Orsay, France; (F.D.); (M.D.); (E.J.)
| | - Alexey Novikov
- HEPHAISTOS-Pharma, Bâtiment 440, Université de Paris-Saclay, 91400 Orsay, France; (C.P.); (A.N.); (J.K.)
| | - Jerome Kerzerho
- HEPHAISTOS-Pharma, Bâtiment 440, Université de Paris-Saclay, 91400 Orsay, France; (C.P.); (A.N.); (J.K.)
| | - Martine Caroff
- LPS-BioSciences, Bâtiment 440, Université de Paris-Saclay, 91400 Orsay, France; (F.D.); (M.D.); (E.J.)
- HEPHAISTOS-Pharma, Bâtiment 440, Université de Paris-Saclay, 91400 Orsay, France; (C.P.); (A.N.); (J.K.)
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2
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Matamoros-Recio A, Merino J, Gallego-Jiménez A, Conde-Alvarez R, Fresno M, Martín-Santamaría S. Immune evasion through Toll-like receptor 4: The role of the core oligosaccharides from α2-Proteobacteria atypical lipopolysaccharides. Carbohydr Polym 2023; 318:121094. [PMID: 37479429 DOI: 10.1016/j.carbpol.2023.121094] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 05/21/2023] [Accepted: 06/04/2023] [Indexed: 07/23/2023]
Abstract
Lipopolysaccharides (LPS) are major players in bacterial infection through the recognition by Toll-like receptor 4 (TLR4). The LPS chemical structure, including the oligosaccharide core and the lipid A moiety, can be strongly influenced by adaptation and modulated to assure bacteria protection, evade immune surveillance, or reduce host immune responses. Deep structural understanding of TLRs signaling is essential for the modulation of the innate immune system in sepsis control and inflammation, during bacterial infection. To advance this knowledge, we have employed computational techniques to characterize the TLR4 molecular recognition of atypical LPSs from different opportunistic members of α2-Proteobacteria, including Brucella melitensis, Ochrobactrum anthropi, and Ochrobactrum intermedium, with diverse immunostimulatory activities. We contribute to unraveling the role of uncommon lipid A chemical features such as bearing very long-chain fatty acid chains, whose presence has been rarely reported, on modulating the proper heterodimerization of the TLR4 receptor complex. Moreover, we further evaluated the influence of the different oligosaccharide cores, including sugar composition and net charge, on TLR4 activation. Our studies contribute to elucidating, from the molecular and biological perspectives, the impact of the α2-Proteobacteria LPS cores and the chemical structure of the atypical lipid A for immune system evasion in opportunistic bacteria.
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Affiliation(s)
- Alejandra Matamoros-Recio
- Department of Structural and Chemical Biology, Centro de Investigaciones Biológicas "Margarita Salas", CSIC, C/ Ramiro de Maeztu, 9, 28040 Madrid, Spain.
| | - Javier Merino
- Centro de Biología Molecular "Severo Ochoa", CSIC-Universidad Autónoma de Madrid, C/ Nicolás Cabrera, 1, 28049 Madrid, Spain
| | - Alicia Gallego-Jiménez
- Centro de Biología Molecular "Severo Ochoa", CSIC-Universidad Autónoma de Madrid, C/ Nicolás Cabrera, 1, 28049 Madrid, Spain
| | - Raquel Conde-Alvarez
- Dpto. de Microbiología y Parasitología, Instituto de Salud Tropical (ISTUN), Instituto de Investigación Sanitaria de Navarra (IdiSNA), Universidad de Navarra, Campus Universitario, 31009 Pamplona, Spain
| | - Manuel Fresno
- Centro de Biología Molecular "Severo Ochoa", CSIC-Universidad Autónoma de Madrid, C/ Nicolás Cabrera, 1, 28049 Madrid, Spain
| | - Sonsoles Martín-Santamaría
- Department of Structural and Chemical Biology, Centro de Investigaciones Biológicas "Margarita Salas", CSIC, C/ Ramiro de Maeztu, 9, 28040 Madrid, Spain.
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3
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Garcia-Vello P, Di Lorenzo F, Zucchetta D, Zamyatina A, De Castro C, Molinaro A. Lipopolysaccharide lipid A: A promising molecule for new immunity-based therapies and antibiotics. Pharmacol Ther 2022; 230:107970. [PMID: 34454000 DOI: 10.1016/j.pharmthera.2021.107970] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Revised: 06/24/2021] [Accepted: 07/22/2021] [Indexed: 12/15/2022]
Abstract
Lipopolysaccharides (LPS) are the main components of the external leaflet of the Gram-negative outer membrane and consist of three different moieties: lipid A, core oligosaccharide, and O-polysaccharide. The lipid A is a glucosamine disaccharide with different levels of acylation and phosphorylation, beside carrying, in certain cases, additional substituents on the sugar backbone. It is also the main immunostimulatory part of the LPS, as its recognition by the host immune system represents a fundamental event for detection of perilous microorganisms. Moreover, an uncontrolled immune response caused by a large amount of circulating LPS can lead to dramatic outcomes for human health, such as septic shock. The immunostimulant properties of an LPS incredibly vary depending on lipid A chemical structure, and for this reason, natural and synthetic variants of the lipid A are under study to develop new drugs that mimic or antagonise its natural effects. Here, we review past and recent findings on the lipid A as an antibiotic target and immune-therapeutic molecule, with a special attention on the crucial role of the chemical structure and its exploitation for conceiving novel strategies for treatment of several immune-related pathologies.
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Affiliation(s)
- Pilar Garcia-Vello
- Department of Chemical Sciences, University of Naples Federico II, Napoli, Italy.
| | - Flaviana Di Lorenzo
- Department of Chemical Sciences, University of Naples Federico II, Napoli, Italy
| | - Daniele Zucchetta
- Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Alla Zamyatina
- Department of Chemistry, University of Natural Resources and Life Sciences, Vienna, Austria
| | - Cristina De Castro
- Department of Agricultural Sciences, University of Naples Federico II, Portici, Italy
| | - Antonio Molinaro
- Department of Chemical Sciences, University of Naples Federico II, Napoli, Italy.
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4
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Francisco S, Billod JM, Merino J, Punzón C, Gallego A, Arranz A, Martin-Santamaria S, Fresno M. Induction of TLR4/TLR2 Interaction and Heterodimer Formation by Low Endotoxic Atypical LPS. Front Immunol 2022; 12:748303. [PMID: 35140704 PMCID: PMC8818788 DOI: 10.3389/fimmu.2021.748303] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Accepted: 12/27/2021] [Indexed: 12/01/2022] Open
Abstract
The Toll-like receptor 4 (TLR4)/myeloid differentiation protein-2 (MD-2) complex is considered the major receptor of the innate immune system to recognize lipopolysaccharides (LPSs). However, some atypical LPSs with different lipid A and core saccharide moiety structures and compositions than the well-studied enterobacterial LPSs can induce a TLR2-dependent response in innate immune cells. Ochrobactrum intermedium, an opportunistic pathogen, presents an atypical LPS. In this study, we found that O. intermedium LPS exhibits a weak inflammatory activity compared to Escherichia coli LPS and, more importantly, is a specific TLR4/TLR2 agonist, able to signal through both receptors. Molecular docking analysis of O. intermedium LPS predicts a favorable formation of a TLR2/TLR4/MD-2 heterodimer complex, which was experimentally confirmed by fluorescence resonance energy transfer (FRET) in cells. Interestingly, the core saccharide plays an important role in this interaction. This study reveals for the first time TLR4/TLR2 heterodimerization that is induced by atypical LPS and may help to escape from recognition by the innate immune system.
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Affiliation(s)
- Sara Francisco
- Diomune S. L., Parque Científico de Madrid, Madrid, Spain
- Department of Molecular Biology, Centro de Biología Molecular “Severo Ochoa”, Consejo Superior de Investigaciones Cientificas (CSIC)-Universidad Autónoma de Madrid, Madrid, Spain
| | - Jean-Marc Billod
- Department of Structural Biology, Centro de Investigaciones Biologicas “Margarita Salas”, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid, Spain
| | - Javier Merino
- Diomune S. L., Parque Científico de Madrid, Madrid, Spain
- Department of Molecular Biology, Centro de Biología Molecular “Severo Ochoa”, Consejo Superior de Investigaciones Cientificas (CSIC)-Universidad Autónoma de Madrid, Madrid, Spain
| | - Carmen Punzón
- Diomune S. L., Parque Científico de Madrid, Madrid, Spain
| | - Alicia Gallego
- Department of Molecular Biology, Centro de Biología Molecular “Severo Ochoa”, Consejo Superior de Investigaciones Cientificas (CSIC)-Universidad Autónoma de Madrid, Madrid, Spain
| | - Alicia Arranz
- Department of Molecular Biology, Centro de Biología Molecular “Severo Ochoa”, Consejo Superior de Investigaciones Cientificas (CSIC)-Universidad Autónoma de Madrid, Madrid, Spain
| | - Sonsoles Martin-Santamaria
- Department of Structural Biology, Centro de Investigaciones Biologicas “Margarita Salas”, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid, Spain
| | - Manuel Fresno
- Diomune S. L., Parque Científico de Madrid, Madrid, Spain
- Department of Molecular Biology, Centro de Biología Molecular “Severo Ochoa”, Consejo Superior de Investigaciones Cientificas (CSIC)-Universidad Autónoma de Madrid, Madrid, Spain
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5
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Moreno E. The one hundred year journey of the genus Brucella (Meyer and Shaw 1920). FEMS Microbiol Rev 2021; 45:5917985. [PMID: 33016322 DOI: 10.1093/femsre/fuaa045] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Accepted: 09/08/2020] [Indexed: 12/18/2022] Open
Abstract
The genus Brucella, described by Meyer and Shaw in 1920, comprises bacterial pathogens of veterinary and public health relevance. For 36 years, the genus came to include three species that caused brucellosis in livestock and humans. In the second half of the 20th century, bacteriologists discovered five new species and several 'atypical' strains in domestic animals and wildlife. In 1990, the Brucella species were recognized as part of the Class Alphaproteobacteria, clustering with pathogens and endosymbionts of animals and plants such as Bartonella, Agrobacterium and Ochrobactrum; all bacteria that live in close association with eukaryotic cells. Comparisons with Alphaproteobacteria contributed to identify virulence factors and to establish evolutionary relationships. Brucella members have two circular chromosomes, are devoid of plasmids, and display close genetic relatedness. A proposal, asserting that all brucellae belong to a single species with several subspecies debated for over 70 years, was ultimately rejected in 2006 by the subcommittee of taxonomy, based on scientific, practical, and biosafety considerations. Following this, the nomenclature of having multiples Brucella species prevailed and defined according to their molecular characteristics, host preference, and virulence. The 100-year history of the genus corresponds to the chronicle of scientific efforts and the struggle for understanding brucellosis.
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Affiliation(s)
- Edgardo Moreno
- Programa de Investigación en Enfermedades Tropicales, Escuela de Medicina Veterinaria, Campues Benjamín Nuñez, Universidad Nacional, Heredia 40104, Costa Rica
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6
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Zhao Y, Hanniffy S, Arce-Gorvel V, Conde-Alvarez R, Oh S, Moriyón I, Mémet S, Gorvel JP. Immunomodulatory properties of Brucella melitensis lipopolysaccharide determinants on mouse dendritic cells in vitro and in vivo. Virulence 2018; 9:465-479. [PMID: 28968180 PMCID: PMC5955181 DOI: 10.1080/21505594.2017.1386831] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022] Open
Abstract
The lipopolysaccharide (LPS) is a major virulence factor of Brucella, a facultative intracellular pathogenic Gram-negative bacterium. Brucella LPS exhibits a low toxicity and its atypical structure was postulated to delay the host immune response, favouring the establishment of chronic disease. Here we carried out an in-depth in vitro and in vivo characterisation of the immunomodulatory effects of Brucella LPS on different dendritic cell (DC) subpopulations. By using LPSs from bacteria that share some of Brucella LPS structural features, we demonstrated that the core component of B. melitensis wild-type (Bm-wt) LPS accounts for the low activation potential of Brucella LPS in mouse GM-CSF-derived (GM-) DCs. Contrary to the accepted dogma considering Brucella LPS a poor TLR4 agonist and DC activator, Bm-wt LPS selectively induced expression of surface activation markers and cytokine secretion from Flt3-Ligand-derived (FL-) DCs in a TLR4-dependent manner. It also primed in vitro T cell proliferation by FL-DCs. In contrast, modified LPS with a defective core purified from Brucella carrying a mutated wadC gene (Bm-wadC), efficiently potentiated mouse and human DC activation and T cell proliferation in vitro. In vivo, Bm-wt LPS promoted scant activation of splenic DC subsets and limited recruitment of monocyte- DC like cells in the spleen, conversely to Bm-wadC LPS. Bm-wadC live bacteria drove high cytokine secretion levels in sera of infected mice. Altogether, these results illustrate the immunomodulatory properties of Brucella LPS and the enhanced DC activation ability of the wadC mutation with potential for vaccine development targeting Brucella core LPS structure.
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Affiliation(s)
- Yun Zhao
- a Centre d'Immunologie de Marseille-Luminy, CIML, Aix Marseille Univ, CNRS, INSERM , Marseille , France
| | - Sean Hanniffy
- a Centre d'Immunologie de Marseille-Luminy, CIML, Aix Marseille Univ, CNRS, INSERM , Marseille , France
| | - Vilma Arce-Gorvel
- a Centre d'Immunologie de Marseille-Luminy, CIML, Aix Marseille Univ, CNRS, INSERM , Marseille , France
| | - Raquel Conde-Alvarez
- b Departamento de Microbiología y Parasitología , Instituto de Salud Tropical, Instituto de Investigación Sanitaria de Navarra, Universidad de Navarra , c/Irunlarrea 1, Pamplona , Spain
| | - SangKon Oh
- c Baylor Institute for Immunology Research , 3434 Live Oak St., Dallas , TX , U.S.A
| | - Ignacio Moriyón
- b Departamento de Microbiología y Parasitología , Instituto de Salud Tropical, Instituto de Investigación Sanitaria de Navarra, Universidad de Navarra , c/Irunlarrea 1, Pamplona , Spain
| | - Sylvie Mémet
- a Centre d'Immunologie de Marseille-Luminy, CIML, Aix Marseille Univ, CNRS, INSERM , Marseille , France
| | - Jean-Pierre Gorvel
- a Centre d'Immunologie de Marseille-Luminy, CIML, Aix Marseille Univ, CNRS, INSERM , Marseille , France
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7
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Hashimoto M, Ozono M, Furuyashiki M, Baba R, Hashiguchi S, Suda Y, Fukase K, Fujimoto Y. Characterization of a Novel d-Glycero-d-talo-oct-2-ulosonic acid-substituted Lipid A Moiety in the Lipopolysaccharide Produced by the Acetic Acid Bacterium Acetobacter pasteurianus NBRC 3283. J Biol Chem 2016; 291:21184-21194. [PMID: 27539854 DOI: 10.1074/jbc.m116.751271] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2016] [Indexed: 01/17/2023] Open
Abstract
Acetobacter pasteurianus is an aerobic Gram-negative rod that is used in the fermentation process used to produce the traditional Japanese black rice vinegar kurozu. Previously, we found that a hydrophobic fraction derived from kurozu stimulates Toll-like receptors to produce cytokines. LPSs, particularly LPS from A. pasteurianus, are strong candidates for the immunostimulatory component of kurozu. The LPS of A. pasteurianus remains stable in acidic conditions during the 2 years of the abovementioned fermentation process. Thus, we hypothesized that its stability results from its structure. In this study, we isolated the LPS produced by A. pasteurianus NBRC 3283 bacterial cells and characterized the structure of its lipid A component. The lipid A moiety was obtained by standard weak acid hydrolysis of the LPS. However, the hydrolysis was incomplete because a certain proportion of the LPS contained acid-stable d-glycero-d-talo-oct-2-ulosonic acid (Ko) residues instead of the acid-labile 3-deoxy-d-manno-oct-2-ulosonic acid residues that are normally found in typical LPS. Even so, we obtained a Ko-substituted lipid A with a novel sugar backbone, α-Man(1-4)[α-Ko(2-6)]β-GlcN3N(1-6)α-GlcN(1-1)α-GlcA. Its reducing end GlcN(1-1)GlcA bond was also found to be quite acid-stable. Six fatty acids were attached to the backbone. Both the whole LPS and the lipid A moiety induced TNF-α production in murine cells via Toll-like receptor 4, although their activity was weaker than those of Escherichia coli LPS and lipid A. These results suggest that the structurally atypical A. pasteurianus lipid A found in this study remains stable and, hence, retains its immunostimulatory activity during acetic acid fermentation.
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Affiliation(s)
- Masahito Hashimoto
- From the Department of Chemistry, Biotechnology, and Chemical Engineering, Kagoshima University, Kagoshima 890-0065, Japan,
| | - Mami Ozono
- From the Department of Chemistry, Biotechnology, and Chemical Engineering, Kagoshima University, Kagoshima 890-0065, Japan
| | - Maiko Furuyashiki
- From the Department of Chemistry, Biotechnology, and Chemical Engineering, Kagoshima University, Kagoshima 890-0065, Japan
| | - Risako Baba
- From the Department of Chemistry, Biotechnology, and Chemical Engineering, Kagoshima University, Kagoshima 890-0065, Japan
| | - Shuhei Hashiguchi
- From the Department of Chemistry, Biotechnology, and Chemical Engineering, Kagoshima University, Kagoshima 890-0065, Japan
| | - Yasuo Suda
- From the Department of Chemistry, Biotechnology, and Chemical Engineering, Kagoshima University, Kagoshima 890-0065, Japan
| | - Koichi Fukase
- the Department of Chemistry, Graduate School of Science, Osaka University, Osaka 560-0043, Japan, and
| | - Yukari Fujimoto
- the Faculty of Science and Technology, Keio University, Kanagawa 223-8522, Japan
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8
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Zhang H, Zhao H, Zhou X, Yang X, Shen S, Wang J, Wang Z, Geng L. Isolation and characterization of antioxidant polysaccharides (PKCP-D70-2-a and PKCP-D70-2-b) from the Pinus koraiensis pinecone. RSC Adv 2016. [DOI: 10.1039/c6ra23205a] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Water-soluble polysaccharides from Pinus koraiensis pinecone was fractionated using DEAE cellulose-52 and Sephadex G-100 successively to obtain two eluents named PKCP-D70-2-a and PKCP-D70-2-b.
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Affiliation(s)
- Hua Zhang
- Department of Food Science and Engineering
- School of Chemistry and Chemical Engineering
- Harbin Institute of Technology
- Harbin
- China
| | - Haitian Zhao
- Department of Food Science and Engineering
- School of Chemistry and Chemical Engineering
- Harbin Institute of Technology
- Harbin
- China
| | - Xintao Zhou
- Department of Food Science and Engineering
- School of Chemistry and Chemical Engineering
- Harbin Institute of Technology
- Harbin
- China
| | - Xin Yang
- Department of Food Science and Engineering
- School of Chemistry and Chemical Engineering
- Harbin Institute of Technology
- Harbin
- China
| | - Siyan Shen
- Department of Food Science and Engineering
- School of Chemistry and Chemical Engineering
- Harbin Institute of Technology
- Harbin
- China
| | - Jing Wang
- Department of Food Science and Engineering
- School of Chemistry and Chemical Engineering
- Harbin Institute of Technology
- Harbin
- China
| | - Zhenyu Wang
- Department of Food Science and Engineering
- School of Chemistry and Chemical Engineering
- Harbin Institute of Technology
- Harbin
- China
| | - Lin Geng
- School of Materials Science and Engineering
- Harbin Institute of Technology
- Harbin
- China
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9
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Gil-Ramírez Y, Conde-Álvarez R, Palacios-Chaves L, Zúñiga-Ripa A, Grilló MJ, Arce-Gorvel V, Hanniffy S, Moriyón I, Iriarte M. The identification of wadB, a new glycosyltransferase gene, confirms the branched structure and the role in virulence of the lipopolysaccharide core of Brucella abortus. Microb Pathog 2014; 73:53-9. [PMID: 24927935 DOI: 10.1016/j.micpath.2014.06.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2014] [Revised: 05/28/2014] [Accepted: 06/03/2014] [Indexed: 12/20/2022]
Abstract
Brucellosis is a worldwide extended zoonosis caused by Brucella spp. These gram-negative bacteria are not readily detected by innate immunity, a virulence-related property largely linked to their surface lipopolysaccharide (LPS). The role of the LPS lipid A and O-polysaccharide in virulence is well known. Moreover, mutation of the glycosyltransferase gene wadC of Brucella abortus, although not affecting O-polysaccharide assembly onto the lipid-A core section causes a core oligosaccharide defect that increases recognition by innate immunity. Here, we report on a second gene (wadB) encoding a LPS core glycosyltransferase not involved in the assembly of the O-polysaccharide-linked core section. As compared to wild-type B. abortus, a wadB mutant was sensitive to bactericidal peptides and non-immune serum, and was attenuated in mice and dendritic cells. These observations show that as WadC, WadB is also involved in the assembly of a branch of Brucella LPS core and support the concept that this LPS section is a virulence-related structure.
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Affiliation(s)
- Yolanda Gil-Ramírez
- Departamento de Microbiología y Parasitología e Instituto de Salud Tropical, Universidad de Navarra, 31008 Pamplona, Spain.
| | - Raquel Conde-Álvarez
- Departamento de Microbiología y Parasitología e Instituto de Salud Tropical, Universidad de Navarra, 31008 Pamplona, Spain.
| | - Leyre Palacios-Chaves
- Departamento de Microbiología y Parasitología e Instituto de Salud Tropical, Universidad de Navarra, 31008 Pamplona, Spain.
| | - Amaia Zúñiga-Ripa
- Departamento de Microbiología y Parasitología e Instituto de Salud Tropical, Universidad de Navarra, 31008 Pamplona, Spain.
| | - María-Jesús Grilló
- Instituto de Agrobiotecnología (CSIC-Universidad Pública de Navarra-Gobierno de Navarra), 31006 Pamplona, Spain.
| | - Vilma Arce-Gorvel
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille University, Centre d'Immunologie de Marseille-Luminy, 13288 Marseille, France; INSERM U1104, 13288 Marseille, France; CNRS UMR7280, 13288 Marseille, France.
| | - Sean Hanniffy
- Centre d'Immunologie de Marseille-Luminy, Aix-Marseille University, Centre d'Immunologie de Marseille-Luminy, 13288 Marseille, France; INSERM U1104, 13288 Marseille, France; CNRS UMR7280, 13288 Marseille, France.
| | - Ignacio Moriyón
- Departamento de Microbiología y Parasitología e Instituto de Salud Tropical, Universidad de Navarra, 31008 Pamplona, Spain.
| | - Maite Iriarte
- Departamento de Microbiología y Parasitología e Instituto de Salud Tropical, Universidad de Navarra, 31008 Pamplona, Spain.
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10
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Lodowska J, Wolny D, Węglarz L. The sugar 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo) as a characteristic component of bacterial endotoxin — a review of its biosynthesis, function, and placement in the lipopolysaccharide core. Can J Microbiol 2013; 59:645-55. [DOI: 10.1139/cjm-2013-0490] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
The sugar 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo) is a characteristic component of bacterial lipopolysaccharide (LPS, endotoxin). It connects the carbohydrate part of LPS with C6 of glucosamine or 2,3-diaminoglucose of lipid A by acid-labile α-ketosidic linkage. The number of Kdo units present in LPS, the way they are connected, and the occurrence of other substituents (P, PEtn, PPEtn, Gal, or β-l-Ara4N) account for structural diversity of the inner core region of endotoxin. In a majority of cases, Kdo is crucial to the viability and growth of bacterial cells. In this paper, the biosynthesis of Kdo and the mechanism of its incorporation into the LPS structure, as well as the location of this unique component in the endotoxin core structures, have been described.
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Affiliation(s)
- Jolanta Lodowska
- Department of Biochemistry, Faculty of Pharmacy, Medical University of Silesia, Narcyzow 1 Street, 41-200 Sosnowiec, Poland
| | - Daniel Wolny
- Department of Biopharmacy, Faculty of Pharmacy, Medical University of Silesia, Narcyzow 1 St., 41-200 Sosnowiec, Poland
| | - Ludmiła Węglarz
- Department of Biochemistry, Faculty of Pharmacy, Medical University of Silesia, Narcyzow 1 Street, 41-200 Sosnowiec, Poland
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11
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Structure and immunogenicity of the rough-type lipopolysaccharide from the periodontal pathogen Tannerella forsythia. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2013; 20:945-53. [PMID: 23616409 DOI: 10.1128/cvi.00139-13] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Tannerella forsythia is a Gram-negative anaerobic organism that inhabits subgingival plaque biofilms and is covered with a so far unique surface layer composed of two glycoproteins. It belongs to the so-called "red complex" of bacteria comprising species that are associated with periodontal disease. While the surface layer glycoprotein glycan structure had been elucidated recently and found to be a virulence factor, no structural data on the lipopolysaccharide (LPS) of this organism were available. In this study, the T. forsythia LPS structure was partially elucidated by a combined mass spectrometry (MS) and nuclear magnetic resonance spectroscopy (NMR) approach and initial experiments to characterize its immunostimulatory potential were performed. The T. forsythia LPS is a complex, rough-type LPS with a core region composed of one 3-deoxy-d-manno-oct-2-ulosonic acid (Kdo) residue, three mannose residues, and two glucosamine residues. MS analyses of O-deacylated LPS proved that, in addition, one phosphoethanolamine residue and most likely one galactose-phosphate residue were present, however, their positions could not be identified. Stimulation of human macrophages with T. forsythia LPS resulted in the production of the proinflammatory cytokines interleukin-1 (IL-1), IL-6, and tumor necrosis factor alpha in a dose-dependent manner. The response to T. forsythia LPS was observed only upon stimulation in the presence of fetal calf serum (FCS), whereas no cytokine production was observed in the absence of FCS. This finding suggests that the presence of certain additional cofactors is crucial for the immune response induced by T. forsythia LPS.
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12
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Kubler-Kielb J, Vinogradov E. The study of the core part and non-repeating elements of the O-antigen of Brucella lipopolysaccharide. Carbohydr Res 2013; 366:33-7. [PMID: 23261780 PMCID: PMC3540177 DOI: 10.1016/j.carres.2012.11.004] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2012] [Revised: 11/09/2012] [Accepted: 11/12/2012] [Indexed: 12/17/2022]
Abstract
Brucella is an animal and human pathogen that expresses several virulence factors required for host cell invasion and intracellular survival. It produces LPS with unusually low toxicity, which hampers the detection of bacteria by the host immune system and thus provides resistance against intracellular antimicrobial mechanisms of the host. By chemical and spectroscopic methods we determined the structure of the LPS core and of a non-repetitive oligosaccharide fragment at the reducing end of the O-specific polysaccharide. These data should be useful for understanding the biological role of the Brucella LPS.
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Affiliation(s)
- Joanna Kubler-Kielb
- Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD, USA
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13
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Zou S, Zhang X, Yao W, Niu Y, Gao X. Structure characterization and hypoglycemic activity of a polysaccharide isolated from the fruit of Lycium barbarum L. Carbohydr Polym 2010. [DOI: 10.1016/j.carbpol.2010.01.038] [Citation(s) in RCA: 105] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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14
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The differential interaction of Brucella and ochrobactrum with innate immunity reveals traits related to the evolution of stealthy pathogens. PLoS One 2009; 4:e5893. [PMID: 19529776 PMCID: PMC2691993 DOI: 10.1371/journal.pone.0005893] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2009] [Accepted: 05/19/2009] [Indexed: 12/13/2022] Open
Abstract
Background During evolution, innate immunity has been tuned to recognize pathogen-associated molecular patterns. However, some α-Proteobacteria are stealthy intracellular pathogens not readily detected by this system. Brucella members follow this strategy and are highly virulent, but other Brucellaceae like Ochrobactrum are rhizosphere inhabitants and only opportunistic pathogens. To gain insight into the emergence of the stealthy strategy, we compared these two phylogenetically close but biologically divergent bacteria. Methodology/Principal Findings In contrast to Brucella abortus, Ochrobactrum anthropi did not replicate within professional and non-professional phagocytes and, whereas neutrophils had a limited action on B. abortus, they were essential to control O. anthropi infections. O. anthropi triggered proinflammatory responses markedly lower than Salmonella enterica but higher than B. abortus. In macrophages and dendritic cells, the corresponding lipopolysaccharides reproduced these grades of activation, and binding of O. anthropi lipopolysaccharide to the TLR4 co-receptor MD-2 and NF-κB induction laid between those of B. abortus and enteric bacteria lipopolysaccharides. These differences correlate with reported variations in lipopolysaccharide core sugars, sensitivity to bactericidal peptides and outer membrane permeability. Conclusions/Significance The results suggest that Brucellaceae ancestors carried molecules not readily recognized by innate immunity, so that non-drastic variations led to the emergence of stealthy intracellular parasites. They also suggest that some critical envelope properties, like selective permeability, are profoundly altered upon modification of pathogen-associated molecular patterns, and that this represents a further adaptation to the host. It is proposed that this adaptive trend is relevant in other intracellular α-Proteobacteria like Bartonella, Rickettsia, Anaplasma, Ehrlichia and Wolbachia.
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15
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De Castro C, Carannante A, Lanzetta R, Lindner B, Nunziata R, Parrilli M, Holst O. Structural Characterisation of the Core Oligosaccharides Isolated from the Lipooligosaccharide Fraction ofAgrobacterium tumefaciens A1. Chemistry 2006; 12:4668-74. [PMID: 16550619 DOI: 10.1002/chem.200501620] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Three different oligosaccharide structures from the lipooligosaccharide fraction of Agrobacterium tumefaciens strain A1 were determined by means of chemical and spectrometrical methods. The peculiar feature of this oligosaccharide family consisted of its unusual length, that was very close to the that minimal requested for the external membrane functionality as exemplified from oligosaccharide 3, where the inner core is glycosylated from only one sugar moiety onwards.
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Affiliation(s)
- Cristina De Castro
- Department of Organic Chemistry and Biochemistry, University of Naples, Complesso Universitario Monte Sant'Angelo, Via Cintia 4, 80126 Naples, Italy.
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16
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Abstract
Bacterial lipopolysaccharides are the major components of the outer surface of Gram-negative bacteria They are often of interest in medicine for their immunomodulatory properties. In small amounts they can be beneficial, but in larger amounts they may cause endotoxic shock. Although they share a common architecture, their structural details exert a strong influence on their activity. These molecules comprise: a lipid moiety, called lipid A, which is considered to be the endotoxic component, a glycosidic part consisting of a core of approximately 10 monosaccharides and, in "smooth-type" lipopolysaccharides, a third region, named O-chain, consisting of repetitive subunits of one to eight monosaccharides responsible for much of the immunospecificity of the bacterial cell.
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Affiliation(s)
- Martine Caroff
- Equipe Endotoxines, UMR 8619 du Centre National de la Recherche Scientifique, IBBMC, Université de Paris-Sud, F-91405 Orsay, France.
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17
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Monreal D, Grilló MJ, González D, Marín CM, De Miguel MJ, López-Goñi I, Blasco JM, Cloeckaert A, Moriyón I. Characterization of Brucella abortus O-polysaccharide and core lipopolysaccharide mutants and demonstration that a complete core is required for rough vaccines to be efficient against Brucella abortus and Brucella ovis in the mouse model. Infect Immun 2003; 71:3261-71. [PMID: 12761107 PMCID: PMC155776 DOI: 10.1128/iai.71.6.3261-3271.2003] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Brucella abortus rough lipopolysaccharide (LPS) mutants were obtained by transposon insertion into two wbk genes (wbkA [putative glycosyltransferase; formerly rfbU] and per [perosamine synthetase]), into manB (pmm [phosphomannomutase; formerly rfbK]), and into an unassigned gene. Consistent with gene-predicted roles, electrophoretic analysis, 2-keto-3-manno-D-octulosonate measurements, and immunoblots with monoclonal antibodies to O-polysaccharide, outer and inner core epitopes showed no O-polysaccharide expression and no LPS core defects in the wbk mutants. The rough LPS of manB mutant lacked the outer core epitope and the gene was designated manB(core) to distinguish it from the wbk manB(O-Ag). The fourth gene (provisionally designated wa**) coded for a putative glycosyltransferase involved in inner core synthesis, but the mutant kept the outer core epitope. Differences in phage and polymyxin sensitivity, exposure or expression of outer membrane protein, core and lipid A epitopes, and lipid A acylation demonstrated that small changes in LPS core caused significant differences in B. abortus outer membrane topology. In mice, the mutants showed different degrees of attenuation and induced antibodies to rough LPS and outer membrane proteins. Core-defective mutants and strain RB51 were ineffective vaccines against B. abortus in mice. The mutants per and wbkA induced protection but less than the standard smooth vaccine S19, and controls suggested that anti O-polysaccharide antibodies accounted largely for the difference. Whereas no core-defective mutant was effective against B. ovis, S19, RB51, and the wbkA and per mutants afforded similar levels of protection. These results suggest that rough Brucella vaccines should carry a complete core for maximal effectiveness.
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Affiliation(s)
- D. Monreal
- Departamento de Microbiología, Universidad de Navarra, Pamplona, Servicio de Investigación Agroalimentaria, Diputación General de Aragón, Zaragoza, Spain, Unité BioAgresseurs, Santé et Environnement, Institut National de la Recherche Agronomique, 37380 Nouzilly, France
| | - M. J. Grilló
- Departamento de Microbiología, Universidad de Navarra, Pamplona, Servicio de Investigación Agroalimentaria, Diputación General de Aragón, Zaragoza, Spain, Unité BioAgresseurs, Santé et Environnement, Institut National de la Recherche Agronomique, 37380 Nouzilly, France
| | - D. González
- Departamento de Microbiología, Universidad de Navarra, Pamplona, Servicio de Investigación Agroalimentaria, Diputación General de Aragón, Zaragoza, Spain, Unité BioAgresseurs, Santé et Environnement, Institut National de la Recherche Agronomique, 37380 Nouzilly, France
| | - C. M. Marín
- Departamento de Microbiología, Universidad de Navarra, Pamplona, Servicio de Investigación Agroalimentaria, Diputación General de Aragón, Zaragoza, Spain, Unité BioAgresseurs, Santé et Environnement, Institut National de la Recherche Agronomique, 37380 Nouzilly, France
| | - M. J. De Miguel
- Departamento de Microbiología, Universidad de Navarra, Pamplona, Servicio de Investigación Agroalimentaria, Diputación General de Aragón, Zaragoza, Spain, Unité BioAgresseurs, Santé et Environnement, Institut National de la Recherche Agronomique, 37380 Nouzilly, France
| | - I. López-Goñi
- Departamento de Microbiología, Universidad de Navarra, Pamplona, Servicio de Investigación Agroalimentaria, Diputación General de Aragón, Zaragoza, Spain, Unité BioAgresseurs, Santé et Environnement, Institut National de la Recherche Agronomique, 37380 Nouzilly, France
| | - J. M. Blasco
- Departamento de Microbiología, Universidad de Navarra, Pamplona, Servicio de Investigación Agroalimentaria, Diputación General de Aragón, Zaragoza, Spain, Unité BioAgresseurs, Santé et Environnement, Institut National de la Recherche Agronomique, 37380 Nouzilly, France
| | - A Cloeckaert
- Departamento de Microbiología, Universidad de Navarra, Pamplona, Servicio de Investigación Agroalimentaria, Diputación General de Aragón, Zaragoza, Spain, Unité BioAgresseurs, Santé et Environnement, Institut National de la Recherche Agronomique, 37380 Nouzilly, France
| | - I. Moriyón
- Departamento de Microbiología, Universidad de Navarra, Pamplona, Servicio de Investigación Agroalimentaria, Diputación General de Aragón, Zaragoza, Spain, Unité BioAgresseurs, Santé et Environnement, Institut National de la Recherche Agronomique, 37380 Nouzilly, France
- Corresponding author. Mailing address: Departamento de Microbiología, Universidad de Navarra, Aptdo. 177, 31080 Pamplona, Spain. Phone: 34-948-425600. Fax: 34-948-425649. E-mail:
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18
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Molinaro A, De Castro C, Lanzetta R, Evidente A, Parrilli M, Holst O. Lipopolysaccharides possessing two L-glycero-D-manno-heptopyranosyl-alpha -(1-->5)-3-deoxy-D-manno-oct-2-ulopyranosonic acid moieties in the core region. The structure of the core region of the lipopolysaccharides from Burkholderia caryophylli. J Biol Chem 2002; 277:10058-63. [PMID: 11790781 DOI: 10.1074/jbc.m110283200] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The carbohydrate backbone of the core-lipid A region was characterized from the lipopolysaccharides (LPSs) of the plant-pathogenic bacterium Burkholderia caryophylli. For the first time, the presence of two moieties of l-glycero-d-manno-heptopyranosyl-alpha-(1-->5)-3-deoxy-d-manno-oct-2-ulopyranosonic acid was identified in a core region, which is of particular interest with regard to the biosynthesis of this and of LPSs in general. The LPSs of B. caryophylli were degraded by mild hydrazinolysis (de-O-acylation), treatment with 48% aqueous HF at 4 degrees C (cleavage of phosphate groups and destruction of the O-specific polysaccharides), reduction with NaBH4, and de-N-acylation utilizing hot KOH. The major oligosaccharide representing the carbohydrate backbone of the core region and lipid A was isolated by high-performance anion-exchange chromatography. Its analysis employing compositional and methylation analyses, matrix-assisted laser desorption/ionization mass spectrometry, and (1)H and (13)C NMR spectroscopy applying various one-dimensional and two-dimensional experiments identified the following structure. Structure I All sugars are pyranoses and alpha-linked, if not stated otherwise. Hep is l-glycero-d-manno-heptose, Kdo is 3-deoxy-d-manno-oct-2-ulosonic acid.
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Affiliation(s)
- Antonio Molinaro
- Dipartimento di Chimica Organica e Biochimica, Università degli studi di Napoli "Federico 11," I-80126 Napoli, Italy
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19
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Koketsu M, Kuberan B, Linhardt RJ. Stereoselective synthesis of the alpha-glycoside of a KDO "C"-disaccharide. Org Lett 2000; 2:3361-3. [PMID: 11029211 DOI: 10.1021/ol006458n] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The reaction of tert-butyl (4,5,7, 8-tetra-O-acetyl-3-deoxy-alpha-D-manno-2-octulopyranosyl chloride)onate donor 7 with the 6-formylgalactopyranoside acceptor 4 in the presence of SmI(2) provided only the KDO alpha-C-disaccharide 8. The bulky tert-butyl ester in the donor was used to reverse the stereochemical outcome of C-glycosylation, stereoselectively forming the alpha-"C"-disaccharide of KDO.
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Affiliation(s)
- M Koketsu
- Departments of Chemistry, Medicinal and Natural Products Chemistry, Chemical and Biochemical Engineering, University of Iowa, Iowa City, Iowa 52242, USA
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20
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Velasco J, Bengoechea JA, Brandenburg K, Lindner B, Seydel U, González D, Zähringer U, Moreno E, Moriyón I. Brucella abortus and its closest phylogenetic relative, Ochrobactrum spp., differ in outer membrane permeability and cationic peptide resistance. Infect Immun 2000; 68:3210-8. [PMID: 10816465 PMCID: PMC97564 DOI: 10.1128/iai.68.6.3210-3218.2000] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The outer membrane (OM) of the intracellular parasite Brucella abortus is permeable to hydrophobic probes and resistant to destabilization by polycationic peptides and EDTA. The significance of these unusual properties was investigated in a comparative study with the opportunistic pathogens of the genus Ochrobactrum, the closest known Brucella relative. Ochrobactrum spp. OMs were impermeable to hydrophobic probes and sensitive to polymyxin B but resistant to EDTA. These properties were traced to lipopolysaccharide (LPS) because (i) insertion of B. abortus LPS, but not of Escherichia coli LPS, into Ochrobactrum OM increased its permeability; (ii) permeability and polymyxin B binding measured with LPS aggregates paralleled the results with live bacteria; and (iii) the predicted intermediate results were obtained with B. abortus-Ochrobactrum anthropi and E. coli-O. anthropi LPS hybrid aggregates. Although Ochrobactrum was sensitive to polymyxin, self-promoted uptake and bacterial lysis occurred without OM morphological changes, suggesting an unusual OM structural rigidity. Ochrobactrum and B. abortus LPSs showed no differences in phosphate, qualitative fatty acid composition, or acyl chain fluidity. However, Ochrobactrum LPS, but not B. abortus LPS, contained galacturonic acid. B. abortus and Ochrobactrum smooth LPS aggregates had similar size and zeta potential (-12 to -15 mV). Upon saturation with polymyxin, zeta potential became positive (1 mV) for Ochrobactrum smooth LPS while remaining negative (-5 mV) for B. abortus smooth LPS, suggesting hindered access to inner targets. These results show that although Ochrobactrum and Brucella share a basic OM pattern, subtle modifications in LPS core cause markedly different OM properties, possibly reflecting the adaptive evolution of B. abortus to pathogenicity.
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Affiliation(s)
- J Velasco
- Departamento de Microbiología, Universidad de Navarra, Pamplona, Spain
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