1
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Zhang G, Hu H, Yin Y, Tian M, Bu Z, Ding C, Yu S. Brucella Manipulates Host Cell Ferroptosis to Facilitate Its Intracellular Replication and Egress in RAW264.7 Macrophages. Antioxidants (Basel) 2024; 13:577. [PMID: 38790682 PMCID: PMC11118192 DOI: 10.3390/antiox13050577] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2024] [Revised: 05/03/2024] [Accepted: 05/07/2024] [Indexed: 05/26/2024] Open
Abstract
Brucella virulence relies on its successful intracellular life cycle. Modulating host cell death is a strategy for Brucella to survive and replicate intracellularly. Ferroptosis is a novel regulated cell death characterized by iron-triggered excessive lipid peroxidation, which has been proven to be associated with pathogenic bacteria infection. Thus, we attempted to explore if smooth-type Brucella infection triggers host cell ferroptosis and what role it plays in Brucella infection. We assessed the effects of Brucella infection on the lactate dehydrogenase release and lipid peroxidation levels of RAW264.7 macrophages; subsequently, we determined the effect of Brucella infection on the expressions of ferroptosis defense pathways. Furthermore, we determined the role of host cell ferroptosis in the intracellular replication and egress of Brucella. The results demonstrated that Brucella M5 could induce ferroptosis of macrophages by inhibiting the GPX4-GSH axis at the late stage of infection but mitigated ferroptosis by up-regulating the GCH1-BH4 axis at the early infection stage. Moreover, elevating host cell ferroptosis decreased Brucella intracellular survival and suppressing host cell ferroptosis increased Brucella intracellular replication and egress. Collectively, Brucella may manipulate host cell ferroptosis to facilitate its intracellular replication and egress, extending our knowledge about the underlying mechanism of how Brucella completes its intracellular life cycle.
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Affiliation(s)
- Guangdong Zhang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China; (G.Z.); (H.H.); (Y.Y.); (M.T.)
- Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Harbin 150069, China;
| | - Hai Hu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China; (G.Z.); (H.H.); (Y.Y.); (M.T.)
| | - Yi Yin
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China; (G.Z.); (H.H.); (Y.Y.); (M.T.)
| | - Mingxing Tian
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China; (G.Z.); (H.H.); (Y.Y.); (M.T.)
| | - Zhigao Bu
- Harbin Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Harbin 150069, China;
| | - Chan Ding
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China; (G.Z.); (H.H.); (Y.Y.); (M.T.)
- Jiangsu Co-Innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou 225009, China
| | - Shengqing Yu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China; (G.Z.); (H.H.); (Y.Y.); (M.T.)
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2
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Sun D, Liu Y, Peng X, Dong H, Jiang H, Fan X, Feng Y, Sun J, Han K, Gao Q, Niu J, Ding J. ClpP protease modulates bacterial growth, stress response, and bacterial virulence in Brucella abortus. Vet Res 2023; 54:68. [PMID: 37612737 PMCID: PMC10464072 DOI: 10.1186/s13567-023-01200-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Accepted: 06/20/2023] [Indexed: 08/25/2023] Open
Abstract
The process of intracellular proteolysis through ATP-dependent proteases is a biologically conserved phenomenon. The stress responses and bacterial virulence of various pathogenic bacteria are associated with the ATP-dependent Clp protease. In this study, a Brucella abortus 2308 strain, ΔclpP, was constructed to characterize the function of ClpP peptidase. The growth of the ΔclpP mutant strain was significantly impaired in the TSB medium. The results showed that the ΔclpP mutant was sensitive to acidic pH stress, oxidative stress, high temperature, detergents, high osmotic environment, and iron deficient environment. Additionally, the deletion of clpP significantly affected Brucella virulence in macrophage and mouse infection models. Integrated transcriptomic and proteomic analyses of the ΔclpP strain showed that 1965 genes were significantly affected at the mRNA and/or protein levels. The RNA-seq analysis indicated that the ΔclpP strain exhibited distinct gene expression patterns related to energy production and conversion, cell wall/membrane/envelope biogenesis, carbohydrate transport, and metabolism. The iTRAQ analysis revealed that the differentially expressed proteins primarily participated in amino acid transport and metabolism, energy production and conversion, and secondary metabolites biosynthesis, transport and catabolism. This study provided insights into the preliminary molecular mechanism between Clp protease to bacterial growth, stress response, and bacterial virulence in Brucella strains.
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Affiliation(s)
- Dongjie Sun
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yufu Liu
- Zhaoqing Institute Biotechnology Co., Ltd., Zhaoqing, China
- Department of Inspection Technology Research, China Institute of Veterinary Drug Control, Beijing, China
| | - Xiaowei Peng
- Department of Inspection Technology Research, China Institute of Veterinary Drug Control, Beijing, China
| | - Hao Dong
- Institute for Laboratory Animal Resources, National Institutes for Food and Drug Control, Beijing, China
| | - Hui Jiang
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xuezheng Fan
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Yu Feng
- Department of Inspection Technology Research, China Institute of Veterinary Drug Control, Beijing, China
| | - Jiali Sun
- Department of Inspection Technology Research, China Institute of Veterinary Drug Control, Beijing, China
| | - Kun Han
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Qiang Gao
- Department of Inspection Technology Research, China Institute of Veterinary Drug Control, Beijing, China
| | | | - Jiabo Ding
- Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
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3
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Tian M, Li Z, Qu J, Fang T, Yin Y, Zuo D, Abdelgawad HA, Hu H, Wang S, Qi J, Wang G, Yu S. The novel LysR-family transcriptional regulator BvtR is involved in the resistance of Brucella abortus to nitrosative stress, detergents and virulence through the genetic regulation of diverse pathways. Vet Microbiol 2022; 267:109393. [PMID: 35259600 DOI: 10.1016/j.vetmic.2022.109393] [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] [Received: 10/31/2021] [Revised: 01/22/2022] [Accepted: 02/28/2022] [Indexed: 11/22/2022]
Abstract
Brucella is a facultative intracellular bacterium lacking classical virulence factors; its virulence instead depends on its ability to invade and proliferate within host cells. After entering cells, Brucella rapidly modulates the expression of a series of genes involved in metabolism and immune evasion. Here, a novel LysR-family transcriptional regulator, designated Brucellavirulence-related transcriptional regulator (BvtR), was found to be associated with Brucella abortus virulence. We first successfully constructed a BvtR mutant, ΔbvtR, and a complemented strain, ΔbvtR-Com. Subsequently, we performed cell infection experiments, which indicated that the ΔbvtR strain exhibited similar adhesion, invasion and survival within HeLa cells or RAW264.7 macrophages to those of the wild-type strain. In stress resistance tests, the ΔbvtR strain showed enhanced sensitivity to sodium nitroprusside and sodium dodecyl sulfate, but not to hydrogen peroxide, cumene hydroperoxide, polymyxin B and natural serum. Mouse infection experiments indicated that the virulence of the ΔbvtR strain significantly decreased at 4 weeks post-infection. Finally, we analyzed differentially expressed genes regulated by BvtR with RNA-seq, COG classification and KEGG pathway analysis. Nitrogen metabolism, siderophore biosynthesis and oligopeptide transport were found to be the predominantly altered functions, and key metabolic and regulatory networks were delineated in the ΔbvtR mutant. Thus, we identified a novel Brucella virulence-related regulator, BvtR, and demonstrated that BvtR regulation affects Brucella resistance to killing by sodium nitroprusside and sodium dodecyl sulfate. The differentially expressed genes responding to BvtR are involved in diverse functions or pathways in Brucella, thus, suggesting the breadth of BvtR's regulatory functions. This study provides novel clues regarding Brucella pathogenesis.
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Affiliation(s)
- Mingxing Tian
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China
| | - Zichen Li
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China
| | - Jing Qu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China; Songjiang District Center for Animal Disease Control and Prevention, Shanghai 201699, China
| | - Tian Fang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China; College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, China
| | - Yi Yin
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China
| | - Dong Zuo
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China
| | - Hosny Ahmed Abdelgawad
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China
| | - Hai Hu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China
| | - Shaohui Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China
| | - Jingjing Qi
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China
| | - Guijun Wang
- College of Animal Science and Technology, Anhui Agricultural University, Hefei 230036, China
| | - Shengqing Yu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai 200241, China.
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4
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Stranahan LW, Arenas-Gamboa AM. When the Going Gets Rough: The Significance of Brucella Lipopolysaccharide Phenotype in Host-Pathogen Interactions. Front Microbiol 2021; 12:713157. [PMID: 34335551 PMCID: PMC8319746 DOI: 10.3389/fmicb.2021.713157] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2021] [Accepted: 06/22/2021] [Indexed: 01/18/2023] Open
Abstract
Brucella is a facultatively intracellular bacterial pathogen and the cause of worldwide zoonotic infections, infamous for its ability to evade the immune system and persist chronically within host cells. Despite the frequent association with attenuation in other Gram-negative bacteria, a rough lipopolysaccharide phenotype is retained by Brucella canis and Brucella ovis, which remain fully virulent in their natural canine and ovine hosts, respectively. While these natural rough strains lack the O-polysaccharide they, like their smooth counterparts, are able to evade and manipulate the host immune system by exhibiting low endotoxic activity, resisting destruction by complement and antimicrobial peptides, entering and trafficking within host cells along a similar pathway, and interfering with MHC-II antigen presentation. B. canis and B. ovis appear to have compensated for their roughness by alterations to their outer membrane, especially in regards to outer membrane proteins. B. canis, in particular, also shows evidence of being less proinflammatory in vivo, suggesting that the rough phenotype may be associated with an enhanced level of stealth that could allow these pathogens to persist for longer periods of time undetected. Nevertheless, much additional work is required to understand the correlates of immune protection against the natural rough Brucella spp., a critical step toward development of much-needed vaccines. This review will highlight the significance of rough lipopolysaccharide in the context of both natural disease and host–pathogen interactions with an emphasis on natural rough Brucella spp. and the implications for vaccine development.
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Affiliation(s)
- Lauren W Stranahan
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
| | - Angela M Arenas-Gamboa
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, TX, United States
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5
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Pessione E. The Less Expensive Choice: Bacterial Strategies to Achieve Successful and Sustainable Reciprocal Interactions. Front Microbiol 2021; 11:571417. [PMID: 33584557 PMCID: PMC7873842 DOI: 10.3389/fmicb.2020.571417] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Accepted: 12/11/2020] [Indexed: 12/22/2022] Open
Abstract
Bacteria, the first organisms that appeared on Earth, continue to play a central role in ensuring life on the planet, both as biogeochemical agents and as higher organisms' symbionts. In the last decades, they have been employed both as bioremediation agents for cleaning polluted sites and as bioconversion effectors for obtaining a variety of products from wastes (including eco-friendly plastics and green energies). However, some recent reports suggest that bacterial biodiversity can be negatively affected by the present environmental crisis (global warming, soil desertification, and ocean acidification). This review analyzes the behaviors positively selected by evolution that render bacteria good models of sustainable practices (urgent in these times of climate change and scarcity of resources). Actually, bacteria display a tendency to optimize rather than maximize, to economize energy and building blocks (by using the same molecule for performing multiple functions), and to recycle and share metabolites, and these are winning strategies when dealing with sustainability. Furthermore, their ability to establish successful reciprocal relationships by means of anticipation, collective actions, and cooperation can also constitute an example highlighting how evolutionary selection favors behaviors that can be strategic to contain the present environmental crisis.
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Affiliation(s)
- Enrica Pessione
- Department of Life Sciences and Systems Biology, Università degli Studi di Torino, Torino, Italy
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6
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Ouahrani-Bettache S, Jiménez De Bagüés MP, De La Garza J, Freddi L, Bueso JP, Lyonnais S, Al Dahouk S, De Biase D, Köhler S, Occhialini A. Lethality of Brucella microti in a murine model of infection depends on the wbkE gene involved in O-polysaccharide synthesis. Virulence 2020; 10:868-878. [PMID: 31635539 PMCID: PMC6844557 DOI: 10.1080/21505594.2019.1682762] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Brucella microti was isolated a decade ago from wildlife and soil in Europe. Compared to the classical Brucella species, it exhibits atypical virulence properties such as increased growth in human and murine macrophages and lethality in experimentally infected mice. A spontaneous rough (R) mutant strain, derived from the smooth reference strain CCM4915T, showed increased macrophage colonization and was non-lethal in murine infections. Whole-genome sequencing and construction of an isogenic mutant of B. microti and Brucella suis 1330 revealed that the R-phenotype was due to a deletion in a single gene, namely wbkE (BMI_I539), encoding a putative glycosyltransferase involved in lipopolysaccharide (LPS) O-polysaccharide biosynthesis. Complementation of the R-strains with the wbkE gene restored the smooth phenotype and the ability of B. microti to kill infected mice. LPS with an intact O-polysaccharide is therefore essential for lethal B. microti infections in the murine model, demonstrating its importance in pathogenesis.
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Affiliation(s)
| | - María P Jiménez De Bagüés
- Unidad de Tecnología en Producción y Sanidad Animal, Centro de Investigación y Tecnología Agroalimentaria, Instituto Agroalimentario de Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | | | - Luca Freddi
- IRIM, CNRS, University Montpellier, INSERM, Montpellier, France
| | - Juan P Bueso
- Laboratorio Agroalimentario, Gobierno de Aragón, Zaragoza, Spain
| | | | - Sascha Al Dahouk
- Department of Biological Safety, German Federal Institute for Risk Assessment, Berlin, Germany
| | - Daniela De Biase
- Department of Medico-Surgical Sciences and Biotechnologies, Sapienza University of Rome, Laboratory affiliated to the Istituto Pasteur Italia - Fondazione Cenci Bolognetti, Latina, Italy
| | - Stephan Köhler
- IRIM, CNRS, University Montpellier, INSERM, Montpellier, France
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7
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A rough Brucella mutant induced macrophage death depends on secretion activity of T4SS, but not on cellular Txnip- and Caspase-2-mediated signaling pathway. Vet Microbiol 2020; 244:108648. [PMID: 32402333 DOI: 10.1016/j.vetmic.2020.108648] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Revised: 03/03/2020] [Accepted: 03/17/2020] [Indexed: 12/30/2022]
Abstract
Brucella is a facultative intracellular bacterium, dividing into smooth- and rough-type Brucella. Smooth-type Brucella can dissociate into rough mutants with cytotoxicity for macrophages during infection, which is critical for Brucella egress and dissemination. However, the mechanism of cytotoxicity infected by rough Brucella is incomplete. In this study, we verified that a rough-type Brucella (RB14 strain) was cytotoxic for macrophages dependent on Type IV secretion system (T4SS). Two specific T4SS VirB4 and VirB11 mutants were constructed, which affect the secretion of T4SS effectors, but not the expression of T4SS components. Cytotoxicity analysis showed that RB14- induced macrophages death depends on T4SS secretion activity. In a further study, 15 reported T4SS effectors were evaluated in inducing macrophage death using over-expression and transfection methods, the results showed that 15 recombinant strains with over-expression of respective effector were not cytotoxicity. In addition, 10 effectors transfected individually, or co-transfected with five effectors barely induced macrophage death, suggesting that all 15 effectors were not associated with macrophage death. Besides, we also evaluated endoplasmic reticulum (ER) stress, Txnip- or Caspase-2 roles in RB14-induced macrophages death. The results showed that inhibition of ER stress, Caspase or Caspase-2 activation was not associated with RB14-infected macrophages death. The casp2 and txnip knockout cells also showed death when infected by the RB14 strain. In all, the RB14-induced macrophage death depends on the secretion activity of T4SS, but not on ER stress, Txnip- or Caspase-2 signal pathway. This study provides a deep insight for rough Brucella-induced macrophage death, which favors for elucidating Brucella infection lifecycle.
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8
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Brucella Periplasmic Protein EipB Is a Molecular Determinant of Cell Envelope Integrity and Virulence. J Bacteriol 2019; 201:JB.00134-19. [PMID: 30936371 DOI: 10.1128/jb.00134-19] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 03/25/2019] [Indexed: 01/18/2023] Open
Abstract
The Gram-negative cell envelope is a remarkable structure with core components that include an inner membrane, an outer membrane, and a peptidoglycan layer in the periplasmic space between. Multiple molecular systems function to maintain integrity of this essential barrier between the interior of the cell and its surrounding environment. We show that a conserved DUF1849 family protein, EipB, is secreted to the periplasmic space of Brucella species, a monophyletic group of intracellular pathogens. In the periplasm, EipB folds into an unusual 14-stranded β-spiral structure that resembles the LolA and LolB lipoprotein delivery system, though the overall fold of EipB is distinct from LolA/LolB. Deletion of eipB results in defects in Brucella cell envelope integrity in vitro and in maintenance of spleen colonization in a mouse model of Brucella abortus infection. Transposon disruption of ttpA, which encodes a periplasmic protein containing tetratricopeptide repeats, is synthetically lethal with eipB deletion. ttpA is a reported virulence determinant in Brucella, and our studies of ttpA deletion and overexpression strains provide evidence that this gene also contributes to cell envelope function. We conclude that eipB and ttpA function in the Brucella periplasmic space to maintain cell envelope integrity, which facilitates survival in a mammalian host.IMPORTANCE Brucella species cause brucellosis, a global zoonosis. A gene encoding a conserved DUF1849-family protein, which we have named EipB, is present in all sequenced Brucella and several other genera in the class Alphaproteobacteria The manuscript provides the first functional and structural characterization of a DUF1849 protein. We show that EipB is secreted to the periplasm where it forms a spiral-shaped antiparallel β protein that is a determinant of cell envelope integrity in vitro and virulence in an animal model of disease. eipB genetically interacts with ttpA, which also encodes a periplasmic protein. We propose that EipB and TtpA function as part of a system required for cell envelope homeostasis in select Alphaproteobacteria.
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9
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Vassen V, Valotteau C, Feuillie C, Formosa-Dague C, Dufrêne YF, De Bolle X. Localized incorporation of outer membrane components in the pathogen Brucella abortus. EMBO J 2019; 38:e100323. [PMID: 30635335 PMCID: PMC6396147 DOI: 10.15252/embj.2018100323] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 11/29/2018] [Accepted: 12/04/2018] [Indexed: 12/21/2022] Open
Abstract
The zoonotic pathogen Brucella abortus is part of the Rhizobiales, which are alpha-proteobacteria displaying unipolar growth. Here, we show that this bacterium exhibits heterogeneity in its outer membrane composition, with clusters of rough lipopolysaccharide co-localizing with the essential outer membrane porin Omp2b, which is proposed to allow facilitated diffusion of solutes through the porin. We also show that the major outer membrane protein Omp25 and peptidoglycan are incorporated at the new pole and the division site, the expected growth sites. Interestingly, lipopolysaccharide is also inserted at the same growth sites. The absence of long-range diffusion of main components of the outer membrane could explain the apparent immobility of the Omp2b clusters, as well as unipolar and mid-cell localizations of newly incorporated outer membrane proteins and lipopolysaccharide. Unipolar growth and limited mobility of surface structures also suggest that new surface variants could arise in a few generations without the need of diluting pre-existing surface antigens.
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Affiliation(s)
- Victoria Vassen
- Research Unit in Biology of Microorganisms (URBM), Narilis University of Namur (UNamur), Namur, Belgium
| | - Claire Valotteau
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain (UCL), Louvain-la-Neuve, Belgium
| | - Cécile Feuillie
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain (UCL), Louvain-la-Neuve, Belgium
| | - Cécile Formosa-Dague
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain (UCL), Louvain-la-Neuve, Belgium
| | - Yves F Dufrêne
- Louvain Institute of Biomolecular Science and Technology, Université catholique de Louvain (UCL), Louvain-la-Neuve, Belgium
- Walloon Excellence in Life Sciences and Biotechnology (WELBIO), Wavre, Belgium
| | - Xavier De Bolle
- Research Unit in Biology of Microorganisms (URBM), Narilis University of Namur (UNamur), Namur, Belgium
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10
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Tian M, Lian Z, Bao Y, Bao S, Yin Y, Li P, Ding C, Wang S, Li T, Qi J, Wang X, Yu S. Identification of a novel, small, conserved hypothetical protein involved inBrucella abortusvirulence by modifying the expression of multiple genes. Transbound Emerg Dis 2018; 66:349-362. [DOI: 10.1111/tbed.13028] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Revised: 09/05/2018] [Accepted: 09/21/2018] [Indexed: 12/26/2022]
Affiliation(s)
- Mingxing Tian
- Shanghai Veterinary Research Institute Chinese Academy of Agricultural Sciences (CAAS) Shanghai China
| | - Zhengmin Lian
- China College of Veterinary Medicine Gansu Agricultural University LanzhouChina
| | - Yanqing Bao
- Shanghai Veterinary Research Institute Chinese Academy of Agricultural Sciences (CAAS) Shanghai China
| | - Shijun Bao
- China College of Veterinary Medicine Gansu Agricultural University LanzhouChina
| | - Yi Yin
- Shanghai Veterinary Research Institute Chinese Academy of Agricultural Sciences (CAAS) Shanghai China
| | - Peng Li
- Shanghai Veterinary Research Institute Chinese Academy of Agricultural Sciences (CAAS) Shanghai China
| | - Chan Ding
- Shanghai Veterinary Research Institute Chinese Academy of Agricultural Sciences (CAAS) Shanghai China
| | - Shaohui Wang
- Shanghai Veterinary Research Institute Chinese Academy of Agricultural Sciences (CAAS) Shanghai China
| | - Tao Li
- Shanghai Veterinary Research Institute Chinese Academy of Agricultural Sciences (CAAS) Shanghai China
| | - Jingjing Qi
- Shanghai Veterinary Research Institute Chinese Academy of Agricultural Sciences (CAAS) Shanghai China
| | - Xiaolan Wang
- Shanghai Veterinary Research Institute Chinese Academy of Agricultural Sciences (CAAS) Shanghai China
| | - Shengqing Yu
- Shanghai Veterinary Research Institute Chinese Academy of Agricultural Sciences (CAAS) Shanghai China
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11
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Hop HT, Arayan LT, Huy TXN, Reyes AWB, Vu SH, Min W, Lee HJ, Rhee MH, Chang HH, Kim S. The Key Role of c-Fos for Immune Regulation and Bacterial Dissemination in Brucella Infected Macrophage. Front Cell Infect Microbiol 2018; 8:287. [PMID: 30186773 PMCID: PMC6110913 DOI: 10.3389/fcimb.2018.00287] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2018] [Accepted: 07/27/2018] [Indexed: 12/25/2022] Open
Abstract
The cellular oncogene c-Fos (c-Fos) is a component of activator protein 1 (AP1), a master transcriptional regulator of cells. The suppression of c-Fos signaling by siRNA treatment resulted in significant induction of TLR4, which subsequently activates p38 and ERK1/2 mitogen-activated protein kinases (MAPKs) and enhances F-actin polymerization, leading to an increase in B. abortus phagocytosis. During B. abortus infection, c-Fos signaling is induced, which activates the downstream innate-immunity signaling cascade for bacterial clearance. The inhibition of c-Fos signaling led to increased production of interleukin 10 (IL-10), which partially suppressed lysosome-mediated killing, resulting in increased survival of B. abortus inside macrophages. We present evidence of the regulatory role played by the c-Fos pathway in proliferation during B. abortus infection; however, this was independent of the anti-Brucella effect of this pathway. Another finding is the essential contribution of c-Fos/TRAIL to infected-cell necrosis, which is a key event in bacterial dissemination. These data provide the mechanism via which c-Fos participates in host defense mechanisms against Brucella infection and in bacterial dissemination by macrophages.
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Affiliation(s)
- Huynh T Hop
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, South Korea
| | - Lauren T Arayan
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, South Korea
| | - Tran X N Huy
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, South Korea
| | - Alisha W B Reyes
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, South Korea
| | - Son H Vu
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, South Korea
| | - WonGi Min
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, South Korea
| | - Hu J Lee
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, South Korea
| | - Man H Rhee
- College of Veterinary Medicine, Kyungpook National University, Daegu, South Korea
| | - Hong H Chang
- Institute of Agriculture and Life Science, Gyeongsang National University, Jinju, South Korea
| | - Suk Kim
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, South Korea.,Institute of Agriculture and Life Science, Gyeongsang National University, Jinju, South Korea
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12
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Tian M, Bao Y, Li P, Hu H, Ding C, Wang S, Li T, Qi J, Wang X, Yu S. The putative amino acid ABC transporter substrate-binding protein AapJ2 is necessary for Brucella virulence at the early stage of infection in a mouse model. Vet Res 2018; 49:32. [PMID: 29598830 PMCID: PMC5874993 DOI: 10.1186/s13567-018-0527-9] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 03/12/2018] [Indexed: 01/17/2023] Open
Abstract
Brucellosis is a zoonotic bacterial disease caused by Brucella spp. The virulence of these bacteria is dependent on their ability to invade and replicate within host cells. In a previous study, a putative gene bab_RS27735 encoding an amino acid ABC transporter substrate-binding protein homologous to AapJ protein was found to be involved in Brucella abortus virulence. In this study, we successfully constructed a bab_RS27735 deletion mutant, Δ27735. Compared with the wild-type strain, the lipopolysaccharide pattern of the mutant was not changed, but the growth ability was slightly defected in the exponential phase. In tolerance tests, sensitivity of the Δ27735 mutant to oxidative stress, bactericidal peptides or low pH was not different from that of the wild-type strain. Cell infection assay showed that the mutant was reduced survival within macrophages but could efficiently escape lysosome degradation. The results of a virulence test showed that the Δ27735 mutant was attenuated in a mouse model at the early stage of infection but recovered its virulence at the late stage of infection. Meanwhile, the development of splenomegaly and histopathological lesions was observed in mice infected with either the wild-type strain or the mutant. These results are in line with the release of IL-12p40 and TNF-α into the peripheral blood of infected mice. Besides, expression of diverse genes was up-regulated in the Δ27735 mutant, which may contribute to the reduced virulence of the mutant. These data elucidated that the bab_RS27735 gene is necessary for B. abortus virulence at the early stage of infection in a mouse model.
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Affiliation(s)
- Mingxing Tian
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Yanqing Bao
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Peng Li
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Hai Hu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Chan Ding
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Shaohui Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Tao Li
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Jingjing Qi
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Xiaolan Wang
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China
| | - Shengqing Yu
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), Shanghai, 200241, China.
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13
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Hop HT, Arayan LT, Huy TXN, Reyes AWB, Baek EJ, Min W, Lee HJ, Rhee MH, Watanabe K, Chang HH, Kim S. Lipocalin 2 (Lcn2) interferes with iron uptake by Brucella abortus and dampens immunoregulation during infection of RAW 264.7 macrophages. Cell Microbiol 2017; 20. [PMID: 29168343 DOI: 10.1111/cmi.12813] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Revised: 11/14/2017] [Accepted: 11/17/2017] [Indexed: 01/19/2023]
Abstract
Lipocalin 2 (Lcn2) is an important innate immunity component against bacterial pathogens. In this study, we report that Lcn2 is induced by Brucella (B.) abortus infection and significantly contributes to the restriction of intracellular survival of Brucella in macrophages. We found that Lcn2 prevented iron uptake by B. abortus through two distinct mechanisms. First, Lcn2 is secreted to capture bacterial siderophore(s) and abrogate iron import by Brucella. Second, Lcn2 decreases the intracellular iron levels during Brucella infection, which probably deprives the invading Brucella of the iron source needed for growth. Suppression of Lcn2 signalling resulted in a marked induction of anti-inflammatory cytokine, interleukin 10, which was shown to play a major role in Lcn2-induced antibrucella immunity. Similarly, interleukin 6 was also found to be increased when Lcn2 signalling is abrogated; however, this induction was thought to be an alternative pathway that rescues the cell from infection when the effective Lnc2 pathway is repressed. Furthermore, Lcn2 deficiency also caused a marked decrease in brucellacidal effectors, such as reactive oxygen species and nitric oxide but not the phagolysosome fusion. Taken together, our results indicate that Lcn2 is required for the efficient restriction of intracellular B. abortus growth that is through limiting iron acquisition and shifting cells to pro-inflammatory brucellacidal activity in murine macrophages.
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Affiliation(s)
- Huynh Tan Hop
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, Republic of Korea
| | - Lauren Togonon Arayan
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, Republic of Korea
| | - Tran Xuan Ngoc Huy
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, Republic of Korea
| | | | - Eun Jin Baek
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, Republic of Korea
| | - Wongi Min
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, Republic of Korea
| | - Hu Jang Lee
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, Republic of Korea
| | - Man Hee Rhee
- College of Veterinary Medicine, Kyungpook National University, Daegu, Republic of Korea
| | - Kenta Watanabe
- The United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi, Japan
| | - Hong Hee Chang
- Institute of Agriculture and Life Science, Gyeongsang National University, Jinju, Republic of Korea
| | - Suk Kim
- Institute of Animal Medicine, College of Veterinary Medicine, Gyeongsang National University, Jinju, Republic of Korea.,Institute of Agriculture and Life Science, Gyeongsang National University, Jinju, Republic of Korea
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14
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Suárez-Esquivel M, Ruiz-Villalobos N, Castillo-Zeledón A, Jiménez-Rojas C, Roop Ii RM, Comerci DJ, Barquero-Calvo E, Chacón-Díaz C, Caswell CC, Baker KS, Chaves-Olarte E, Thomson NR, Moreno E, Letesson JJ, De Bolle X, Guzmán-Verri C. Brucella abortus Strain 2308 Wisconsin Genome: Importance of the Definition of Reference Strains. Front Microbiol 2016; 7:1557. [PMID: 27746773 PMCID: PMC5041503 DOI: 10.3389/fmicb.2016.01557] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2016] [Accepted: 09/16/2016] [Indexed: 12/25/2022] Open
Abstract
Brucellosis is a bacterial infectious disease affecting a wide range of mammals and a neglected zoonosis caused by species of the genetically homogenous genus Brucella. As in most studies on bacterial diseases, research in brucellosis is carried out by using reference strains as canonical models to understand the mechanisms underlying host pathogen interactions. We performed whole genome sequencing analysis of the reference strain B. abortus 2308 routinely used in our laboratory, including manual curated annotation accessible as an editable version through a link at https://en.wikipedia.org/wiki/Brucella#Genomics. Comparison of this genome with two publically available 2308 genomes showed significant differences, particularly indels related to insertional elements, suggesting variability related to the transposition of these elements within the same strain. Considering the outcome of high resolution genomic techniques in the bacteriology field, the conventional concept of strain definition needs to be revised.
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Affiliation(s)
- Marcela Suárez-Esquivel
- Programa de Investigación en Enfermedades Tropicales, Escuela de Medicina Veterinaria, Universidad Nacional de Costa Rica Heredia, Costa Rica
| | - Nazareth Ruiz-Villalobos
- Programa de Investigación en Enfermedades Tropicales, Escuela de Medicina Veterinaria, Universidad Nacional de Costa Rica Heredia, Costa Rica
| | - Amanda Castillo-Zeledón
- Programa de Investigación en Enfermedades Tropicales, Escuela de Medicina Veterinaria, Universidad Nacional de Costa Rica Heredia, Costa Rica
| | - César Jiménez-Rojas
- Programa de Investigación en Enfermedades Tropicales, Escuela de Medicina Veterinaria, Universidad Nacional de Costa Rica Heredia, Costa Rica
| | - R Martin Roop Ii
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University Greenville, NC, USA
| | - Diego J Comerci
- Instituto de Investigaciones Biotecnológicas "Dr. Rodolfo A. Ugalde", Instituto Tecnológico de Chascomús, Universidad Nacional de San Martín, Consejo Nacional de Investigaciones Científicas y Técnicas, Comisión Nacional de Energía Atómica, Grupo Pecuario, Centro Atómico Ezeiza Buenos Aires, Argentina
| | - Elías Barquero-Calvo
- Centro de Investigación en Enfermedades Tropicales, Facultad de Microbiología, Universidad de Costa Rica San José, Costa Rica
| | - Carlos Chacón-Díaz
- Programa de Investigación en Enfermedades Tropicales, Escuela de Medicina Veterinaria, Universidad Nacional de Costa RicaHeredia, Costa Rica; Centro de Investigación en Enfermedades Tropicales, Facultad de Microbiología, Universidad de Costa RicaSan José, Costa Rica
| | - Clayton C Caswell
- Center for Molecular Medicine and Infectious Diseases, Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech Blacksburg, VA, USA
| | - Kate S Baker
- Wellcome Trust Sanger InstituteHinxton, UK; Department of Functional and Comparative Genomics, Institute of Integrative Biology, University of LiverpoolLiverpool, UK
| | - Esteban Chaves-Olarte
- Centro de Investigación en Enfermedades Tropicales, Facultad de Microbiología, Universidad de Costa Rica San José, Costa Rica
| | - Nicholas R Thomson
- Wellcome Trust Sanger InstituteHinxton, UK; The London School of Hygiene and Tropical MedicineLondon, UK
| | - Edgardo Moreno
- Programa de Investigación en Enfermedades Tropicales, Escuela de Medicina Veterinaria, Universidad Nacional de Costa RicaHeredia, Costa Rica; Instituto Clodomiro Picado, Universidad de Costa RicaSan José, Costa Rica
| | - Jean J Letesson
- Unité de Recherche en Biologie des Microorganismes, Université de Namur Namur Belgium
| | - Xavier De Bolle
- Unité de Recherche en Biologie des Microorganismes, Université de Namur Namur Belgium
| | - Caterina Guzmán-Verri
- Programa de Investigación en Enfermedades Tropicales, Escuela de Medicina Veterinaria, Universidad Nacional de Costa RicaHeredia, Costa Rica; Centro de Investigación en Enfermedades Tropicales, Facultad de Microbiología, Universidad de Costa RicaSan José, Costa Rica
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15
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Pandey A, Cabello A, Akoolo L, Rice-Ficht A, Arenas-Gamboa A, McMurray D, Ficht TA, de Figueiredo P. The Case for Live Attenuated Vaccines against the Neglected Zoonotic Diseases Brucellosis and Bovine Tuberculosis. PLoS Negl Trop Dis 2016; 10:e0004572. [PMID: 27537413 PMCID: PMC4990199 DOI: 10.1371/journal.pntd.0004572] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Vaccination of humans and animals with live attenuated organisms has proven to be an effective means of combatting some important infectious diseases. In fact, the 20th century witnessed tremendous improvements in human and animal health worldwide as a consequence of large-scale vaccination programs with live attenuated vaccines (LAVs). Here, we use the neglected zoonotic diseases brucellosis and bovine tuberculosis (BTb) caused by Brucella spp. and Mycobacterium bovis (M. bovis), respectively, as comparative models to outline the merits of LAV platforms with emphasis on molecular strategies that have been pursued to generate LAVs with enhanced vaccine safety and efficacy profiles. Finally, we discuss the prospects of LAV platforms in the fight against brucellosis and BTb and outline new avenues for future research towards developing effective vaccines using LAV platforms.
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Affiliation(s)
- Aseem Pandey
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, Texas, United States of America
- Department of Veterinary Pathobiology, Texas A&M University, College Station, Texas, United States of America
- Norman Borlaug Center, Texas A&M University, College Station, Texas, United States of America
- * E-mail: (AP); (PdF)
| | - Ana Cabello
- Department of Veterinary Pathobiology, Texas A&M University, College Station, Texas, United States of America
| | - Lavoisier Akoolo
- Department of Veterinary Pathobiology, Texas A&M University, College Station, Texas, United States of America
| | - Allison Rice-Ficht
- Department of Veterinary Pathobiology, Texas A&M University, College Station, Texas, United States of America
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, Bryan, Texas, United States of America
| | - Angela Arenas-Gamboa
- Department of Veterinary Pathobiology, Texas A&M University, College Station, Texas, United States of America
| | - David McMurray
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, Texas, United States of America
| | - Thomas A. Ficht
- Department of Veterinary Pathobiology, Texas A&M University, College Station, Texas, United States of America
| | - Paul de Figueiredo
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, Texas, United States of America
- Department of Veterinary Pathobiology, Texas A&M University, College Station, Texas, United States of America
- Norman Borlaug Center, Texas A&M University, College Station, Texas, United States of America
- * E-mail: (AP); (PdF)
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16
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Fontana C, Conde-Álvarez R, Ståhle J, Holst O, Iriarte M, Zhao Y, Arce-Gorvel V, Hanniffy S, Gorvel JP, Moriyón I, Widmalm G. Structural Studies of Lipopolysaccharide-defective Mutants from Brucella melitensis Identify a Core Oligosaccharide Critical in Virulence. J Biol Chem 2016; 291:7727-41. [PMID: 26867577 PMCID: PMC4817197 DOI: 10.1074/jbc.m115.701540] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Indexed: 11/07/2022] Open
Abstract
The structures of the lipooligosaccharides from Brucella melitensis mutants affected in the WbkD and ManBcore proteins have been fully characterized using NMR spectroscopy. The results revealed that disruption of wbkD gives rise to a rough lipopolysaccharide (R-LPS) with a complete core structure (β-d-Glcp-(1→4)-α-Kdop-(2→4)[β-d-GlcpN-(1→6)-β-d-GlcpN-(1→4)[β-d-GlcpN-(1→6)]-β-d-GlcpN-(1→3)-α-d-Manp-(1→5)]-α-Kdop-(2→6)-β-d-GlcpN3N4P-(1→6)-α-d-GlcpN3N1P), in addition to components lacking one of the terminal β-d-GlcpN and/or the β-d-Glcp residues (48 and 17%, respectively). These structures were identical to those of the R-LPS from B. melitensis EP, a strain simultaneously expressing both smooth and R-LPS, also studied herein. In contrast, disruption of manBcore gives rise to a deep-rough pentasaccharide core (β-d-Glcp-(1→4)-α-Kdop-(2→4)-α-Kdop-(2→6)-β-d-GlcpN3N4P-(1→6)-α-d-GlcpN3N1P) as the major component (63%), as well as a minor tetrasaccharide component lacking the terminal β-d-Glcp residue (37%). These results are in agreement with the predicted functions of the WbkD (glycosyltransferase involved in the biosynthesis of the O-antigen) and ManBcore proteins (phosphomannomutase involved in the biosynthesis of a mannosyl precursor needed for the biosynthesis of the core and O-antigen). We also report that deletion of B. melitensis wadC removes the core oligosaccharide branch not linked to the O-antigen causing an increase in overall negative charge of the remaining LPS inner section. This is in agreement with the mannosyltransferase role predicted for WadC and the lack of GlcpN residues in the defective core oligosaccharide. Despite carrying the O-antigen essential in B. melitensis virulence, the core deficiency in the wadC mutant structure resulted in a more efficient detection by innate immunity and attenuation, proving the role of the β-d-GlcpN-(1→6)-β-d-GlcpN-(1→4)[β-d-GlcpN-(1→6)]-β-d-GlcpN-(1→3)-α-d-Manp-(1→5) structure in virulence.
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Affiliation(s)
- Carolina Fontana
- From the Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden
| | - Raquel Conde-Álvarez
- the Instituto de Salud Tropical, Instituto de Investigación Sanitaria de Navarra, and Departamento de Microbiología y Parasitología, Universidad de Navarra, c/Irunlarrea 1, 31008 Pamplona, Spain
| | - Jonas Ståhle
- From the Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden
| | - Otto Holst
- the Division of Structural Biochemistry, Leibniz-Center for Medicine and Biosciences, Priority Area Asthma and Allergy, Research Center Borstel, Airway Research Center North, Member of the German Center for Lung Research, D-23845 Borstel, Germany
| | - Maite Iriarte
- the Instituto de Salud Tropical, Instituto de Investigación Sanitaria de Navarra, and Departamento de Microbiología y Parasitología, Universidad de Navarra, c/Irunlarrea 1, 31008 Pamplona, Spain
| | - Yun Zhao
- the Centre d'Immunologie de Marseille-Luminy Aix-Marseille University, UM2 Marseille, France
| | - Vilma Arce-Gorvel
- the Centre d'Immunologie de Marseille-Luminy Aix-Marseille University, UM2 Marseille, France, INSERM, U1104 Marseille, France, and CNRS, UMR7280 Marseille, France
| | - Seán Hanniffy
- the Centre d'Immunologie de Marseille-Luminy Aix-Marseille University, UM2 Marseille, France, INSERM, U1104 Marseille, France, and CNRS, UMR7280 Marseille, France
| | - Jean-Pierre Gorvel
- the Centre d'Immunologie de Marseille-Luminy Aix-Marseille University, UM2 Marseille, France, INSERM, U1104 Marseille, France, and CNRS, UMR7280 Marseille, France
| | - Ignacio Moriyón
- the Instituto de Salud Tropical, Instituto de Investigación Sanitaria de Navarra, and Departamento de Microbiología y Parasitología, Universidad de Navarra, c/Irunlarrea 1, 31008 Pamplona, Spain
| | - Göran Widmalm
- From the Department of Organic Chemistry, Arrhenius Laboratory, Stockholm University, S-106 91 Stockholm, Sweden,
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17
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Mancilla M. Smooth to Rough Dissociation in Brucella: The Missing Link to Virulence. Front Cell Infect Microbiol 2016; 5:98. [PMID: 26779449 PMCID: PMC4700419 DOI: 10.3389/fcimb.2015.00098] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2015] [Accepted: 12/10/2015] [Indexed: 11/24/2022] Open
Abstract
Dissociation encompasses changes in a series of phenotypes: colony and cell morphology, inmunological and biochemical reactions and virulence. The concept is generally associated to the in vitro transition between smooth (S) and rough (R) colonies, a phenotypic observation in Gram-negative bacteria commonly made since the beginning of microbiology as a science. It is also well known that the loss of the O-polysaccharide, the most external lipopolysaccharide (LPS) moiety, triggers the change in the colony phenotype. Although dissociation is related to one of the most basic features used to distinguish between species, i.e., colony morphology, and, in the case of pathogens, predict their virulence behavior, it has been considered a laboratory artifact and thus did not gain further attention. However, recent insights into genetics and pathogenesis of members of Brucella, causative agents of brucellosis, have brought a new outlook on this experimental fact, suggesting that it plays a role beyond the laboratory observations. In this perspective article, the current knowledge on Brucella LPS genetics and its connection with dissociation in the frame of evolution is discussed. Latest reports support the notion that, by means of a better understanding of genetic pathways linked to R phenotype and the biological impact of this intriguing "old" phenomenon, unexpected applications can be achieved.
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Affiliation(s)
- Marcos Mancilla
- Research and Development Department, ADL Diagnostic Chile Ltd.Puerto Montt, Chile
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18
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Phenotypic and genotypic characterization of Brucella strains isolated from autochthonous livestock reveals the dominance of B. abortus biovar 3a in Nigeria. Vet Microbiol 2015; 180:103-8. [DOI: 10.1016/j.vetmic.2015.08.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 07/30/2015] [Accepted: 08/14/2015] [Indexed: 12/31/2022]
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19
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Abstract
Clinical tests based on primer-initiated amplification of specific nucleic acid sequences achieve high levels of sensitivity and specificity. Despite these desirable characteristics, these tests have not reached their full potential because their complexity and expense limit their usefulness to centralized laboratories. This paper describes a device that integrates sample preparation and loop-mediated isothermal amplification (LAMP) with end point detection using a hand-held UV source and camera phone. The prototype device integrates paper microfluidics (to enable fluid handling) and a multilayer structure, or a "paper machine", that allows a central patterned paper strip to slide in and out of fluidic path and thus allows introduction of sample, wash buffers, amplification master mix, and detection reagents with minimal pipetting, in a hand-held, disposable device intended for point-of-care use in resource-limited environments. This device creates a dynamic seal that prevents evaporation during incubation at 65 °C for 1 h. This interval is sufficient to allow a LAMP reaction for the Escherichia coli malB gene to proceed with an analytical sensitivity of 1 double-stranded DNA target copy. Starting with human plasma spiked with whole, live E. coli cells, this paper demonstrates full integration of sample preparation with LAMP amplification and end point detection with a limit of detection of 5 cells. Further, it shows that the method used to prepare sample enables concentration of DNA from sample volumes commonly available from fingerstick blood draw.
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Affiliation(s)
- John T Connelly
- †Diagnostics For All, 840 Memorial Drive, Cambridge, Massachusetts 02139, United States
| | - Jason P Rolland
- †Diagnostics For All, 840 Memorial Drive, Cambridge, Massachusetts 02139, United States
| | - George M Whitesides
- ‡Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
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20
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Mechanism of Asp24 upregulation in Brucella abortus rough mutant with a disrupted O-antigen export system and effect of Asp24 in bacterial intracellular survival. Infect Immun 2014; 82:2840-50. [PMID: 24752516 DOI: 10.1128/iai.01765-14] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
We previously showed that Brucella abortus rough mutant strain 2308 ΔATP (called the ΔrfbE mutant in this study) exhibits reduced intracellular survival in RAW264.7 cells and attenuated persistence in BALB/c mice. In this study, we performed microarray analysis to detect genes with differential expression between the ΔrfbE mutant and wild-type strain S2308. Interestingly, acid shock protein 24 gene (asp24) expression was significantly upregulated in the ΔrfbE mutant compared to S2308, as confirmed by quantitative reverse transcription-PCR (qRT-PCR) and Western blotting. Further studies using additional strains indicated that the upregulation of asp24 occurred only in rough mutants with disrupted O-antigen export system components, including the ATP-binding protein gene rfbE (bab1_0542) and the permease gene rfbD (bab1_0543), while the ΔwboA rough mutant (which lacks an O-antigen synthesis-related glycosyltransferase) and the RB51 strain (a vaccine strain with the rough phenotype) showed no significant changes in asp24 expression compared to S2308. In addition, abolishing the intracellular O-antigen synthesis of the ΔrfbE mutant by deleting the wboA gene (thereby creating the ΔrfbE ΔwboA double-knockout strain) recovered asp24 expression. These results indicated that asp24 upregulation is associated with intracellular O-antigen synthesis and accumulation but not with the bacterial rough phenotype. Further studies indicated that asp24 upregulation in the ΔrfbE mutant was associated neither with bacterial adherence and invasion nor with cellular necrosis on RAW264.7 macrophages. However, proper expression of the asp24 gene favors intracellular survival of Brucella in RAW264.7 cells and HeLa cells during an infection. This study reveals a novel mechanism for asp24 upregulation in B. abortus mutants.
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21
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Pei J, Kahl-McDonagh M, Ficht TA. Brucella dissociation is essential for macrophage egress and bacterial dissemination. Front Cell Infect Microbiol 2014; 4:23. [PMID: 24634889 PMCID: PMC3942807 DOI: 10.3389/fcimb.2014.00023] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2013] [Accepted: 02/10/2014] [Indexed: 12/24/2022] Open
Abstract
It has long been observed that smooth Brucella can dissociate into rough mutants that are cytotoxic to macrophages. However, the in vivo biological significance and/or mechanistic details of Brucella dissociation and cytotoxicity remain incomplete. In the current report, a plaque assay was developed using Brucella strains exhibiting varying degrees of cytotoxicity. Infected monolayers were observed daily using phase contrast microscopy for plaque formation while Brucella uptake and replication were monitored using an immunofluorescence assay (IFA). Visible plaques were detected at 4-5 days post infection (p.i.) with cytotoxic Brucella 16MΔmanBA at an MOI of 0.1. IFA staining demonstrated that the plaques consisted of macrophages with replicating Brucella. Visible plaques were not detected in monolayers infected with non-cytotoxic 16MΔmanBAΔvirB2 at an MOI of 0.1. However, IFA staining did reveal small groups of macrophages (foci) with replicating Brucella in the monolayers infected with 16MΔmanBAΔvirB2. The size of the foci observed in macrophage monolayers infected with rough Brucella correlated directly with cytotoxicity measured in liquid culture, suggesting that cytotoxicity was essential for Brucella egress and dissemination. In monolayers infected with 16M, small and large foci were observed. Double antibody staining revealed spontaneous rough mutants within the large, but not the small foci in 16M infected monolayers. Furthermore, plaque formation was observed in the large foci derived from 16M infections. Finally, the addition of gentamicin to the culture medium inhibited plaque formation, suggesting that cell-to-cell spread occurred only following release of the organisms from the cells. Taken together, these results demonstrate that Brucella-induced cytotoxicity is critical for Brucella egress and dissemination.
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Affiliation(s)
| | | | - Thomas A. Ficht
- Department of Veterinary Pathobiology, Texas A&M University and Texas Agricultural Experiment StationCollege Station, TX, USA
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22
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Mancilla M, Grilló MJ, de Miguel MJ, López-Goñi I, San-Román B, Zabalza-Baranguá A, Moriyón I. Deletion of the GI-2 integrase and the wbkA flanking transposase improves the stability of Brucella melitensis Rev 1 vaccine. Vet Res 2013; 44:105. [PMID: 24176078 PMCID: PMC4176087 DOI: 10.1186/1297-9716-44-105] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2013] [Accepted: 10/21/2013] [Indexed: 12/17/2022] Open
Abstract
Brucella melitensis Rev 1 is the best vaccine available for the prophylaxis of small ruminant brucellosis and, indirectly, for reducing human brucellosis. However, Rev 1 shows anomalously high rates of spontaneous dissociation from smooth (S) to rough (R) bacteria, the latter being inefficacious as vaccines. This S-R instability results from the loss of the O-polysaccharide. To overcome this problem, we investigated whether some recently described mechanisms promoting mutations in O-polysaccharide genes were involved in Rev 1 S-R dissociation. We found that a proportion of Rev 1 R mutants result from genome rearrangements affecting the wbo O-polysaccharide loci of genomic island GI-2 and the wbkA O-polysaccharide glycosyltransferase gene of the wbk region. Accordingly, we mutated the GI-2 int gene and the wbk IS transposase involved in those arrangements, and found that these Rev 1 mutants maintained the S phenotype and showed lower dissociation levels. Combining these two mutations resulted in a strain (Rev 2) displaying a 95% decrease in dissociation with respect to parental Rev 1 under conditions promoting dissociation. Rev 2 did not differ from Rev 1 in the characteristics used in Rev 1 typing (growth rate, colonial size, reactivity with O-polysaccharide antibodies, phage, dye and antibiotic susceptibility). Moreover, Rev 2 and Rev 1 showed similar attenuation and afforded similar protection in the mouse model of brucellosis vaccines. We conclude that mutations targeting genes and DNA sequences involved in spontaneous O-polysaccharide loss enhance the stability of a critical vaccine phenotype and complement the empirical stabilization precautions taken during S Brucella vaccine production.
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Affiliation(s)
- Marcos Mancilla
- Departamento de Microbiología y Parasitología e Instituto de Salud Tropical, Universidad de Navarra, C/ Irunlarrea, 1, 31008 Pamplona, Spain
- Instituto de Bioquímica y Microbiología, Universidad Austral de Chile, Campus Isla Teja, casilla 567, Valdivia, Chile
| | - María-Jesús Grilló
- Grupo de Sanidad Animal, Instituto de Agrobiotecnología (CSIC-Universidad Pública de Navarra-Gobierno de Navarra), Campus de Arrosadía, 31006 Pamplona, Spain
| | - María-Jesús de Miguel
- Unidad de Sanidad Animal, Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), Gobierno de Aragón. Av. Montañana, 930, 50059 Zaragoza, Spain
| | - Ignacio López-Goñi
- Departamento de Microbiología y Parasitología e Instituto de Salud Tropical, Universidad de Navarra, C/ Irunlarrea, 1, 31008 Pamplona, Spain
| | - Beatriz San-Román
- Grupo de Sanidad Animal, Instituto de Agrobiotecnología (CSIC-Universidad Pública de Navarra-Gobierno de Navarra), Campus de Arrosadía, 31006 Pamplona, Spain
| | - Ana Zabalza-Baranguá
- Grupo de Sanidad Animal, Instituto de Agrobiotecnología (CSIC-Universidad Pública de Navarra-Gobierno de Navarra), Campus de Arrosadía, 31006 Pamplona, Spain
| | - Ignacio Moriyón
- Departamento de Microbiología y Parasitología e Instituto de Salud Tropical, Universidad de Navarra, C/ Irunlarrea, 1, 31008 Pamplona, Spain
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Gomez G, Adams LG, Rice-Ficht A, Ficht TA. Host-Brucella interactions and the Brucella genome as tools for subunit antigen discovery and immunization against brucellosis. Front Cell Infect Microbiol 2013; 3:17. [PMID: 23720712 PMCID: PMC3655278 DOI: 10.3389/fcimb.2013.00017] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2012] [Accepted: 04/26/2013] [Indexed: 01/18/2023] Open
Abstract
Vaccination is the most important approach to counteract infectious diseases. Thus, the development of new and improved vaccines for existing, emerging, and re-emerging diseases is an area of great interest to the scientific community and general public. Traditional approaches to subunit antigen discovery and vaccine development lack consideration for the critical aspects of public safety and activation of relevant protective host immunity. The availability of genomic sequences for pathogenic Brucella spp. and their hosts have led to development of systems-wide analytical tools that have provided a better understanding of host and pathogen physiology while also beginning to unravel the intricacies at the host-pathogen interface. Advances in pathogen biology, host immunology, and host-agent interactions have the potential to serve as a platform for the design and implementation of better-targeted antigen discovery approaches. With emphasis on Brucella spp., we probe the biological aspects of host and pathogen that merit consideration in the targeted design of subunit antigen discovery and vaccine development.
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Affiliation(s)
- Gabriel Gomez
- Department of Veterinary Pathobiology, Texas A&M University College Station, TX 77843, USA.
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Grilló MJ, Blasco JM, Gorvel JP, Moriyón I, Moreno E. What have we learned from brucellosis in the mouse model? Vet Res 2012; 43:29. [PMID: 22500859 PMCID: PMC3410789 DOI: 10.1186/1297-9716-43-29] [Citation(s) in RCA: 162] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2011] [Accepted: 04/13/2012] [Indexed: 01/18/2023] Open
Abstract
Brucellosis is a zoonosis caused by Brucella species. Brucellosis research in natural hosts is often precluded by practical, economical and ethical reasons and mice are widely used. However, mice are not natural Brucella hosts and the course of murine brucellosis depends on bacterial strain virulence, dose and inoculation route as well as breed, genetic background, age, sex and physiological statu of mice. Therefore, meaningful experiments require a definition of these variables. Brucella spleen replication profiles are highly reproducible and course in four phases: i), onset or spleen colonization (first 48 h); ii), acute phase, from the third day to the time when bacteria reach maximal numbers; iii), chronic steady phase, where bacterial numbers plateaus; and iv), chronic declining phase, during which brucellae are eliminated. This pattern displays clear physiopathological signs and is sensitive to small virulence variations, making possible to assess attenuation when fully virulent bacteria are used as controls. Similarly, immunity studies using mice with known defects are possible. Mutations affecting INF-γ, TLR9, Myd88, Tγδ and TNF-β favor Brucella replication; whereas IL-1β, IL-18, TLR4, TLR5, TLR2, NOD1, NOD2, GM-CSF, IL/17r, Rip2, TRIF, NK or Nramp1 deficiencies have no noticeable effects. Splenomegaly development is also useful: it correlates with IFN-γ and IL-12 levels and with Brucella strain virulence. The genetic background is also important: Brucella-resistant mice (C57BL) yield lower splenic bacterial replication and less splenomegaly than susceptible breeds. When inoculum is increased, a saturating dose above which bacterial numbers per organ do not augment, is reached. Unlike many gram-negative bacteria, lethal doses are large (≥ 108 bacteria/mouse) and normally higher than the saturating dose. Persistence is a useful virulence/attenuation index and is used in vaccine (Residual Virulence) quality control. Vaccine candidates are also often tested in mice by determining splenic Brucella numbers after challenging with appropriate virulent brucellae doses at precise post-vaccination times. Since most live or killed Brucella vaccines provide some protection in mice, controls immunized with reference vaccines (S19 or Rev1) are critical. Finally, mice have been successfully used to evaluate brucellosis therapies. It is concluded that, when used properly, the mouse is a valuable brucellosis model.
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Affiliation(s)
- María-Jesús Grilló
- Instituto de Agrobiotecnología, CSIC-UPNA-Gobierno de Navarra, Pamplona, Spain
| | - José María Blasco
- Centro de Investigación y Tecnología Agroalimentaria (CITA) de Aragón, Zaragoza, Spain
| | - Jean Pierre Gorvel
- Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, Faculté de Sciences de Luminy, Luminy, France
- Institut National de la Santé et de la Recherche Médicale U631, Marseille, France
- Centre National de la Recherche Scientifique UMR6102, Marseille, France
| | - Ignacio Moriyón
- Departamento de Microbiología y Parasitología, Universidad de Navarra, Pamplona, Spain
- Instituto de Salud Tropical, Universidad de Navarra, Pamplona, Spain
| | - Edgardo Moreno
- Programa de Investigación en Enfermedades Tropicales, Escuela de Medicina Veterinaria, Universidad Nacional, Heredia, Costa Rica
- Instituto Clodomiro Picado, Facultad de Microbiología, Universidad de Costa Rica, San José, Costa Rica
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Mancilla M, Marín CM, Blasco JM, Zárraga AM, López-Goñi I, Moriyón I. Spontaneous excision of the O-polysaccharide wbkA glycosyltranferase gene is a cause of dissociation of smooth to rough Brucella colonies. J Bacteriol 2012; 194:1860-7. [PMID: 22328663 PMCID: PMC3318470 DOI: 10.1128/jb.06561-11] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2011] [Accepted: 01/27/2012] [Indexed: 01/07/2023] Open
Abstract
The brucellae are Gram-negative pathogens that cause brucellosis, a zoonosis of worldwide importance. The genus Brucella includes smooth and rough species that differ in that they carry smooth and rough lipopolysaccharides, respectively. Brucella abortus, B. melitensis, and B. suis are typical smooth species. However, these smooth brucellae dissociate into rough mutants devoid of the lipopolysaccharide O-polysaccharide, a major antigen and a virulence determinant encoded in regions wbo (included in genomic island-2) and wbk. We demonstrate here the occurrence of spontaneous recombination events in those three Brucella species leading to the deletion of a 5.5-kb fragment carrying the wbkA glycosyltranferase gene and to the appearance of rough mutants. Analysis of the recombination intermediates suggested homologous recombination between the ISBm1 insertion sequences flanking wbkA as the mechanism generating the deletion. Excision of wbkA was reduced but not abrogated in a recA-deficient mutant, showing the existence of both RecA-dependent and -independent processes. Although the involvement of the ISBm1 copies flanking wbkA suggested a transpositional event, the predicted transpositional joint could not be detected. This absence of detectable transposition was consistent with the presence of polymorphism in the inverted repeats of one of the ISBm1 copies. The spontaneous excision of wbkA represents a novel dissociation mechanism of smooth brucellae that adds to the previously described excision of genomic island-2. This ISBm1-mediated wbkA excision and the different %GC levels of the excised fragment and of other wbk genes suggest that the Brucella wbk locus is the result of at least two horizontal acquisition events.
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Affiliation(s)
- Marcos Mancilla
- Instituto de Salud Tropical y Departamento de Microbiología y Parasitología, Universidad de Navarra, Pamplona, Spain
| | - Clara M. Marín
- Centro de Investigación y Tecnología Agroalimentaria, Unidad de Sanidad Animal, Gobierno de Aragón, Zaragoza, Spain
| | - José M. Blasco
- Centro de Investigación y Tecnología Agroalimentaria, Unidad de Sanidad Animal, Gobierno de Aragón, Zaragoza, Spain
| | - Ana María Zárraga
- Instituto de Bioquímica y Microbiología, Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile
| | - Ignacio López-Goñi
- Instituto de Salud Tropical y Departamento de Microbiología y Parasitología, Universidad de Navarra, Pamplona, Spain
| | - Ignacio Moriyón
- Instituto de Salud Tropical y Departamento de Microbiología y Parasitología, Universidad de Navarra, Pamplona, Spain
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26
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von Bargen K, Gorvel JP, Salcedo SP. Internal affairs: investigating the Brucella intracellular lifestyle. FEMS Microbiol Rev 2012; 36:533-62. [PMID: 22373010 DOI: 10.1111/j.1574-6976.2012.00334.x] [Citation(s) in RCA: 153] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2011] [Revised: 01/10/2012] [Accepted: 02/16/2012] [Indexed: 01/18/2023] Open
Abstract
Bacteria of the genus Brucella are Gram-negative pathogens of several animal species that cause a zoonotic disease in humans known as brucellosis or Malta fever. Within their hosts, brucellae reside within different cell types where they establish a replicative niche and remain protected from the immune response. The aim of this article is to discuss recent advances in the field in the specific context of the Brucella intracellular 'lifestyle'. We initially discuss the different host cell targets and their relevance during infection. As it represents the key to intracellular replication, the focus is then set on the maturation of the Brucella phagosome, with particular emphasis on the Brucella factors that are directly implicated in intracellular trafficking and modulation of host cell signalling pathways. Recent data on the role of the type IV secretion system are discussed, novel effector molecules identified and how some of them impact on trafficking events. Current knowledge on Brucella gene regulation and control of host cell death are summarized, as they directly affect intracellular persistence. Understanding how Brucella molecules interplay with their host cell targets to modulate cellular functions and establish the intracellular niche will help unravel how this pathogen causes disease.
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Affiliation(s)
- Kristine von Bargen
- Faculté de Sciences de Luminy, Centre d'Immunologie de Marseille-Luminy, Aix Marseille Université, UM 2, Marseille Cedex, France
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