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Zubair M, Wang J, Yu Y, Faisal M, Qi M, Shah AU, Feng Z, Shao G, Wang Y, Xiong Q. Proteomics approaches: A review regarding an importance of proteome analyses in understanding the pathogens and diseases. Front Vet Sci 2022; 9:1079359. [PMID: 36601329 PMCID: PMC9806867 DOI: 10.3389/fvets.2022.1079359] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Accepted: 11/28/2022] [Indexed: 12/23/2022] Open
Abstract
Proteomics is playing an increasingly important role in identifying pathogens, emerging and re-emerging infectious agents, understanding pathogenesis, and diagnosis of diseases. Recently, more advanced and sophisticated proteomics technologies have transformed disease diagnostics and vaccines development. The detection of pathogens is made possible by more accurate and time-constrained technologies, resulting in an early diagnosis. More detailed and comprehensive information regarding the proteome of any noxious agent is made possible by combining mass spectrometry with various gel-based or short-gun proteomics approaches recently. MALDI-ToF has been proved quite useful in identifying and distinguishing bacterial pathogens. Other quantitative approaches are doing their best to investigate bacterial virulent factors, diagnostic markers and vaccine candidates. Proteomics is also helping in the identification of secreted proteins and their virulence-related functions. This review aims to highlight the role of cutting-edge proteomics approaches in better understanding the functional genomics of pathogens. This also underlines the limitations of proteomics in bacterial secretome research.
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Affiliation(s)
- Muhammad Zubair
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Jia Wang
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Yanfei Yu
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China,School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China,College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China
| | - Muhammad Faisal
- Division of Hematology, Department of Medicine, The Ohio State University College of Medicine, The Ohio State University Comprehensive Cancer Center, Columbus, OH, United States
| | - Mingpu Qi
- College of Veterinary Medicine, Huazhong Agricultural University, Wuhan, China
| | - Abid Ullah Shah
- National Research Centre of Engineering and Technology for Veterinary Biologicals, Institute of Veterinary Immunology and Engineering, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Zhixin Feng
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China
| | - Guoqing Shao
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China,School of Food and Biological Engineering, Jiangsu University, Zhenjiang, China
| | - Yu Wang
- China Pharmaceutical University, Nanjing, China,*Correspondence: Yu Wang
| | - Qiyan Xiong
- Key Laboratory of Veterinary Biological Engineering and Technology, Ministry of Agriculture, Institute of Veterinary Medicine, Jiangsu Academy of Agricultural Sciences, Nanjing, China,College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, China,School of Life Sciences, Jiangsu University, Zhenjiang, China,Qiyan Xiong
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Minjárez-Sáenz M, Martínez-Júlvez M, Yruela I, Medina M. Mining the Flavoproteome of Brucella ovis, the Brucellosis Causing Agent in Ovis aries. Microbiol Spectr 2022; 10:e0229421. [PMID: 35315701 PMCID: PMC9045290 DOI: 10.1128/spectrum.02294-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Accepted: 02/19/2022] [Indexed: 11/20/2022] Open
Abstract
Flavoproteins are a diverse class of proteins that are mostly enzymes and contain as cofactors flavin mononucleotide (FMN) and/or flavin adenine dinucleotide (FAD), which enable them to participate in a wide range of physiological reactions. We have compiled 78 potential proteins building the flavoproteome of Brucella ovis (B. ovis), the causative agent of ovine brucellosis. The curated list of flavoproteins here reported is based on (i) the analysis of sequence, structure and function of homologous proteins, and their classification according to their structural domains, clans, and expected enzymatic functions; (ii) the constructed phylogenetic trees of enzyme functional classes using 19 Brucella strains and 26 pathogenic and/or biotechnological relevant alphaproteobacteria together with B. ovis; and (iii) the evaluation of the genetic context for each entry. Candidates account for ∼2.7% of the B. ovis proteome, and 75% of them use FAD as cofactor. Only 55% of these flavoproteins belong to the core proteome of Brucella and contribute to B. ovis processes involved in maintenance activities, survival and response to stress, virulence, and/or infectivity. Several of the predicted flavoproteins are highly divergent in Brucella genus from revised proteins and for them it is difficult to envisage a clear function. This might indicate modified catalytic activities or even divergent processes and mechanisms still not identified. We have also detected the lack of some functional flavoenzymes in B. ovis, which might contribute to it being nonzoonotic. Finally, potentiality of B. ovis flavoproteome as the source of antimicrobial targets or biocatalyst is discussed. IMPORTANCE Some microorganisms depend heavily on flavin-dependent activities, but others maintain them at a minimum. Knowledge about flavoprotein content and functions in different microorganisms will help to identify their metabolic requirements, as well as to benefit either industry or health. Currently, most flavoproteins from the sheep pathogen Brucella ovis are only automatically annotated in databases, and only two have been experimentally studied. Indeed, certain homologues with unknown function are not characterized, and they might relate to still not identified mechanisms or processes. Our research has identified 78 members that comprise its flavoproteome, 76 of them flavoenzymes, which mainly relate to bacteria survival, virulence, and/or infectivity. The list of flavoproteins here presented allows us to better understand the peculiarities of Brucella ovis and can be applied as a tool to search for candidates as new biocatalyst or antimicrobial targets.
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Affiliation(s)
- Martha Minjárez-Sáenz
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain
- Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), Universidad de Zaragoza, Zaragoza, Spain
| | - Marta Martínez-Júlvez
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain
- Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), Universidad de Zaragoza, Zaragoza, Spain
- Group of Biochemistry, Biophysics and Computational Biology “GBsC” (BIFI, Unizar) Joint Unit to CSIC, Zaragoza, Spain
| | - Inmaculada Yruela
- Estación Experimental de Aula Dei, CSIC, Zaragoza, Spain
- Group of Biochemistry, Biophysics and Computational Biology “GBsC” (BIFI, Unizar) Joint Unit to CSIC, Zaragoza, Spain
| | - Milagros Medina
- Departamento de Bioquímica y Biología Molecular y Celular, Facultad de Ciencias, Universidad de Zaragoza, Zaragoza, Spain
- Instituto de Biocomputación y Física de Sistemas Complejos (BIFI), Universidad de Zaragoza, Zaragoza, Spain
- Group of Biochemistry, Biophysics and Computational Biology “GBsC” (BIFI, Unizar) Joint Unit to CSIC, Zaragoza, Spain
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3
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Duncan D, Auclair K. Itaconate: an antimicrobial metabolite of macrophages. CAN J CHEM 2022. [DOI: 10.1139/cjc-2021-0117] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Itaconate is a conjugated 1,4-dicarboxylate produced by macrophages. This small molecule has recently received increasing attention due to its role in modulating the immune response of macrophages upon exposure to pathogens. Itaconate has also been proposed to play an antimicrobial function; however, this has not been explored as intensively. Consistent with the latter, itaconate is known to show antibacterial activity in vitro and was reported to inhibit isocitrate lyase, an enzyme required for survival of bacterial pathogens in mammalian systems. Recent studies have revealed bacterial growth inhibition under biologically relevant conditions. In addition, an antimicrobial role for itaconate is substantiated by the high concentration of itaconate found in bacteria-containing vacuoles, and by the production of itaconate-degrading enzymes in pathogens such as Salmonella enterica ser. Typhimurium, Pseudomonas aeruginosa, and Yersinia pestis. This review describes the current state of literature in understanding the role of itaconate as an antimicrobial agent in host–pathogen interactions.
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Affiliation(s)
- Dustin Duncan
- Department of Chemistry, McGill University, Montreal, QC H3A 0B8, Canada
- Department of Chemistry, McGill University, Montreal, QC H3A 0B8, Canada
| | - Karine Auclair
- Department of Chemistry, McGill University, Montreal, QC H3A 0B8, Canada
- Department of Chemistry, McGill University, Montreal, QC H3A 0B8, Canada
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MyD88-Dependent Glucose Restriction and Itaconate Production Control Brucella Infection. Infect Immun 2021; 89:e0015621. [PMID: 34125603 DOI: 10.1128/iai.00156-21] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Brucellosis is one of the most common global zoonoses and is caused by facultative intracellular bacteria of the genus Brucella. Numerous studies have found that MyD88 signaling contributes to protection against Brucella, however the underlying mechanism has not been entirely defined. Here we show that MyD88 signaling in hematopoietic cells contributes both to inflammation and to control of Brucella melitensis infection in vivo. While the protective role of MyD88 in Brucella infection has often been attributed to promotion of IFN-γ production, we found that MyD88 signaling restricts host colonization by B. melitensis even in the absence of IFN-γ. In vitro, we show that MyD88 promotes macrophage glycolysis in response to B. melitensis. Interestingly, a B. melitensis mutant lacking the glucose transporter, GluP, was more highly attenuated in MyD88-/- than in WT mice, suggesting MyD88 deficiency results in an increased availability of glucose in vivo which Brucella can exploit via GluP. Metabolite profiling of macrophages identified several metabolites regulated by MyD88 in response to B. melitensis, including itaconate. Subsequently, we found that itaconate has antibacterial effects against Brucella and also regulates the production of pro-inflammatory cytokines in B. melitensis-infected macrophages. Mice lacking the ability to produce itaconate were also more susceptible to B. melitensis in vivo. Collectively, our findings indicate that MyD88-dependent changes in host metabolism contribute to control of Brucella infection.
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Phenn J, Pané-Farré J, Meukow N, Klein A, Troitzsch A, Tan P, Fuchs S, Wagner GE, Lichtenegger S, Steinmetz I, Kohler C. RegAB Homolog of Burkholderia pseudomallei is the Master Regulator of Redox Control and involved in Virulence. PLoS Pathog 2021; 17:e1009604. [PMID: 34048488 PMCID: PMC8191878 DOI: 10.1371/journal.ppat.1009604] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2020] [Revised: 06/10/2021] [Accepted: 05/03/2021] [Indexed: 12/23/2022] Open
Abstract
Burkholderia pseudomallei, the etiological agent of melioidosis in humans and animals, often occupies environmental niches and infection sites characterized by limited concentrations of oxygen. Versatile genomic features enable this pathogen to maintain its physiology and virulence under hypoxia, but the crucial regulatory networks employed to switch from oxygen dependent respiration to alternative terminal electron acceptors (TEA) like nitrate, remains poorly understood. Here, we combined a Tn5 transposon mutagenesis screen and an anaerobic growth screen to identify a two-component signal transduction system with homology to RegAB. We show that RegAB is not only essential for anaerobic growth, but also for full virulence in cell lines and a mouse infection model. Further investigations of the RegAB regulon, using a global transcriptomic approach, identified 20 additional regulators under transcriptional control of RegAB, indicating a superordinate role of RegAB in the B. pseudomallei anaerobiosis regulatory network. Of the 20 identified regulators, NarX/L and a FNR homolog were selected for further analyses and a role in adaptation to anaerobic conditions was demonstrated. Growth experiments identified nitrate and intermediates of the denitrification process as the likely signal activateing RegAB, NarX/L, and probably of the downstream regulators Dnr or NsrR homologs. While deletions of individual genes involved in the denitrification process demonstrated their important role in anaerobic fitness, they showed no effect on virulence. This further highlights the central role of RegAB as the master regulator of anaerobic metabolism in B. pseudomallei and that the complete RegAB-mediated response is required to achieve full virulence. In summary, our analysis of the RegAB-dependent modulon and its interconnected regulons revealed a key role for RegAB of B. pseudomallei in the coordination of the response to hypoxic conditions and virulence, in the environment and the host.
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Affiliation(s)
- Julia Phenn
- Friedrich Loeffler Institute of Medical Microbiology, University Medicine Greifswald, Greifswald, Germany
| | - Jan Pané-Farré
- SYNMIKRO Research Center and Department of Chemistry, Philipps-University Marburg, Marburg, Germany
| | - Nikolai Meukow
- Friedrich Loeffler Institute of Medical Microbiology, University Medicine Greifswald, Greifswald, Germany
| | - Annelie Klein
- Friedrich Loeffler Institute of Medical Microbiology, University Medicine Greifswald, Greifswald, Germany
| | - Anne Troitzsch
- Department for Microbial Physiology and Molecular Biology, University Greifswald, Greifswald, Germany
| | - Patrick Tan
- Genome Institute of Singapore, Singapore, Republic of Singapore
- Duke-NUS Medical School Singapore, Singapore, Republic of Singapore
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Republic of Singapore
| | - Stephan Fuchs
- FG13 Nosocomial Pathogens and Antibiotic Resistances, Robert Koch Institute, Wernigerode, Germany
| | - Gabriel E Wagner
- Institute of Hygiene, Microbiology and Environmental Medicine, Medical University Graz, Graz, Austria
| | - Sabine Lichtenegger
- Institute of Hygiene, Microbiology and Environmental Medicine, Medical University Graz, Graz, Austria
| | - Ivo Steinmetz
- Friedrich Loeffler Institute of Medical Microbiology, University Medicine Greifswald, Greifswald, Germany
- Institute of Hygiene, Microbiology and Environmental Medicine, Medical University Graz, Graz, Austria
| | - Christian Kohler
- Friedrich Loeffler Institute of Medical Microbiology, University Medicine Greifswald, Greifswald, Germany
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Roop RM, Barton IS, Hopersberger D, Martin DW. Uncovering the Hidden Credentials of Brucella Virulence. Microbiol Mol Biol Rev 2021; 85:e00021-19. [PMID: 33568459 PMCID: PMC8549849 DOI: 10.1128/mmbr.00021-19] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Bacteria in the genus Brucella are important human and veterinary pathogens. The abortion and infertility they cause in food animals produce economic hardships in areas where the disease has not been controlled, and human brucellosis is one of the world's most common zoonoses. Brucella strains have also been isolated from wildlife, but we know much less about the pathobiology and epidemiology of these infections than we do about brucellosis in domestic animals. The brucellae maintain predominantly an intracellular lifestyle in their mammalian hosts, and their ability to subvert the host immune response and survive and replicate in macrophages and placental trophoblasts underlies their success as pathogens. We are just beginning to understand how these bacteria evolved from a progenitor alphaproteobacterium with an environmental niche and diverged to become highly host-adapted and host-specific pathogens. Two important virulence determinants played critical roles in this evolution: (i) a type IV secretion system that secretes effector molecules into the host cell cytoplasm that direct the intracellular trafficking of the brucellae and modulate host immune responses and (ii) a lipopolysaccharide moiety which poorly stimulates host inflammatory responses. This review highlights what we presently know about how these and other virulence determinants contribute to Brucella pathogenesis. Gaining a better understanding of how the brucellae produce disease will provide us with information that can be used to design better strategies for preventing brucellosis in animals and for preventing and treating this disease in humans.
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Affiliation(s)
- R Martin Roop
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Ian S Barton
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Dariel Hopersberger
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
| | - Daniel W Martin
- Department of Microbiology and Immunology, Brody School of Medicine, East Carolina University, Greenville, North Carolina, USA
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Abstract
Brucella spp. are Gram negative intracellular bacteria responsible for brucellosis, a worldwide distributed zoonosis. A prominent aspect of the Brucella life cycle is its ability to invade, survive and multiply within host cells. Comprehensive approaches, such as proteomics, have aided in unravelling the molecular mechanisms underlying Brucella pathogenesis. Technological and methodological advancements such as increased instrument performance and multiplexed quantification have broadened the range of proteome studies, enabling new and improved analyses, providing deeper and more accurate proteome coverage. Indeed, proteomics has demonstrated its contribution to key research questions in Brucella biology, i.e., immunodominant proteins, host-cell interaction, stress response, antibiotic targets and resistance, protein secretion. Here, we review the proteomics of Brucella with a focus on more recent works and novel findings, ranging from reconfiguration of the intracellular bacterial proteome and studies on proteomic profiles of Brucella infected tissues, to the identification of Brucella extracellular proteins with putative roles in cell signaling and pathogenesis. In conclusion, proteomics has yielded copious new candidates and hypotheses that require future verification. It is expected that proteomics will continue to be an invaluable tool for Brucella and applications will further extend to the currently ill-explored aspects including, among others, protein processing and post-translational modification.
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Boggiatto PM, Fitzsimmons D, Bayles DO, Alt D, Vrentas CE, Olsen SC. Coincidence cloning recovery of Brucella melitensis RNA from goat tissues: advancing the in vivo analysis of pathogen gene expression in brucellosis. BMC Mol Biol 2018; 19:10. [PMID: 30068312 PMCID: PMC6071331 DOI: 10.1186/s12867-018-0111-x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2017] [Accepted: 07/24/2018] [Indexed: 11/10/2022] Open
Abstract
Background Brucella melitensis bacteria cause persistent, intracellular infections in small ruminants as well as in humans, leading to significant morbidity and economic loss worldwide. The majority of experiments on the transcriptional responses of Brucella to conditions inside the host have been performed following invasion of cultured mammalian cells, and do not address gene expression patterns during long-term infection. Results Here, we examine the application of the previously developed coincidence cloning methodology to recover and characterize B. melitensis RNA from the supramammary lymph node of experimentally-infected goats. Using coincidence cloning, we successfully recovered Brucella RNA from supramammary lymph nodes of B. melitensis-infected goats at both short-term (4 weeks) and long-term (38 weeks) infection time points. Amplified nucleic acid levels were sufficient for analysis of Brucella gene expression patterns by RNA-sequencing, providing evidence of metabolic activity in both the short-term and the long-term samples. We developed a workflow for the use of sequence polymorphism analysis to confirm recovery of the inoculated strain in the recovered reads, and utilized clustering analysis to demonstrate a distinct transcriptional profile present in samples recovered in long-term infection. In this first look at B. melitensis gene expression patterns in vivo, the subset of Brucella genes that was highly upregulated in long-term as compared to short-term infection included genes linked to roles in murine infection, such as genes involved in proline utilization and signal transduction. Finally, we demonstrated the challenges of qPCR validation of samples with very low ratios of pathogen:host RNA, as is the case during in vivo brucellosis, and alternatively characterized intermediate products of the coincidence cloning reaction. Conclusions Overall, this study provides the first example of recovery plus characterization of B. melitensis RNA from in vivo lymph node infection, and demonstrates that the coincidence cloning technique is a useful tool for characterizing in vivo transcriptional changes in Brucella species. Genes upregulated in long-term infection in this data set, including many genes not previously demonstrated to be virulence factors in mice or macrophage experiments, are candidates of future interest for potential roles in Brucella persistence in natural host systems. Electronic supplementary material The online version of this article (10.1186/s12867-018-0111-x) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Paola M Boggiatto
- Infectious Bacterial Diseases Research Unit, National Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Ames, IA, 50010, USA
| | - Daniel Fitzsimmons
- Infectious Bacterial Diseases Research Unit, National Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Ames, IA, 50010, USA
| | - Darrell O Bayles
- Infectious Bacterial Diseases Research Unit, National Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Ames, IA, 50010, USA
| | - David Alt
- Infectious Bacterial Diseases Research Unit, National Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Ames, IA, 50010, USA
| | - Catherine E Vrentas
- Infectious Bacterial Diseases Research Unit, National Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Ames, IA, 50010, USA.
| | - Steven C Olsen
- Infectious Bacterial Diseases Research Unit, National Animal Disease Center, Agricultural Research Service, U.S. Department of Agriculture, Ames, IA, 50010, USA
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Zúñiga-Ripa A, Barbier T, Lázaro-Antón L, de Miguel MJ, Conde-Álvarez R, Muñoz PM, Letesson JJ, Iriarte M, Moriyón I. The Fast-Growing Brucella suis Biovar 5 Depends on Phosphoenolpyruvate Carboxykinase and Pyruvate Phosphate Dikinase but Not on Fbp and GlpX Fructose-1,6-Bisphosphatases or Isocitrate Lyase for Full Virulence in Laboratory Models. Front Microbiol 2018; 9:641. [PMID: 29675004 PMCID: PMC5896264 DOI: 10.3389/fmicb.2018.00641] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 03/19/2018] [Indexed: 12/14/2022] Open
Abstract
Bacteria of the genus Brucella infect a range of vertebrates causing a worldwide extended zoonosis. The best-characterized brucellae infect domestic livestock, behaving as stealthy facultative intracellular parasites. This stealthiness depends on envelope molecules with reduced pathogen-associated molecular patterns, as revealed by the low lethality and ability to persist in mice of these bacteria. Infected cells are often engorged with brucellae without signs of distress, suggesting that stealthiness could also reflect an adaptation of the parasite metabolism to use local nutrients without harming the cell. To investigate this, we compared key metabolic abilities of Brucella abortus 2308 Wisconsin (2308W), a cattle biovar 1 virulent strain, and B. suis 513, the reference strain of the ancestral biovar 5 found in wild rodents. B. suis 513 used a larger number of C substrates and showed faster growth rates in vitro, two features similar to those of B. microti, a species phylogenomically close to B. suis biovar 5 that infects voles. However, whereas B. microti shows enhanced lethality and reduced persistence in mice, B. suis 513 was similar to B. abortus 2308W in this regard. Mutant analyses showed that B. suis 513 and B. abortus 2308W were similar in that both depend on phosphoenolpyruvate synthesis for virulence but not on the classical gluconeogenic fructose-1,6-bisphosphatases Fbp-GlpX or on isocitrate lyase (AceA). However, B. suis 513 used pyruvate phosphate dikinase (PpdK) and phosphoenolpyruvate carboxykinase (PckA) for phosphoenolpyruvate synthesis in vitro while B. abortus 2308W used only PpdK. Moreover, whereas PpdK dysfunction causes attenuation of B. abortus 2308W in mice, in B. suis, 513 attenuation occurred only in the double PckA-PpdK mutant. Also contrary to what occurs in B. abortus 2308, a B. suis 513 malic enzyme (Mae) mutant was not attenuated, and this independence of Mae and the role of PpdK was confirmed by the lack of attenuation of a double Mae-PckA mutant. Altogether, these results decouple fast growth rates from enhanced mouse lethality in the brucellae and suggest that an Fbp-GlpX-independent gluconeogenic mechanism is ancestral in this group and show differences in central C metabolic steps that may reflect a progressive adaptation to intracellular growth.
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Affiliation(s)
- Amaia Zúñiga-Ripa
- Departamento de Microbiología y Parasitología e Instituto de Salud Tropical - Instituto de Investigación Sanitaria de Navarra, Universidad de Navarra, Pamplona, Spain
| | - Thibault Barbier
- Research Unit in Biology of Microorganisms, Namur Research Institute for Life Sciences, University of Namur, Namur, Belgium
| | - Leticia Lázaro-Antón
- Departamento de Microbiología y Parasitología e Instituto de Salud Tropical - Instituto de Investigación Sanitaria de Navarra, Universidad de Navarra, Pamplona, Spain
| | - María J de Miguel
- Unidad de Producción y Sanidad Animal, Instituto Agroalimentario de Aragón, Centro de Investigación y Tecnología Agroalimentaria de Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | - Raquel Conde-Álvarez
- Departamento de Microbiología y Parasitología e Instituto de Salud Tropical - Instituto de Investigación Sanitaria de Navarra, Universidad de Navarra, Pamplona, Spain
| | - Pilar M Muñoz
- Unidad de Producción y Sanidad Animal, Instituto Agroalimentario de Aragón, Centro de Investigación y Tecnología Agroalimentaria de Aragón, Universidad de Zaragoza, Zaragoza, Spain
| | - Jean J Letesson
- Research Unit in Biology of Microorganisms, Namur Research Institute for Life Sciences, University of Namur, Namur, Belgium
| | - Maite Iriarte
- Departamento de Microbiología y Parasitología e Instituto de Salud Tropical - Instituto de Investigación Sanitaria de Navarra, Universidad de Navarra, Pamplona, Spain
| | - Ignacio Moriyón
- Departamento de Microbiología y Parasitología e Instituto de Salud Tropical - Instituto de Investigación Sanitaria de Navarra, Universidad de Navarra, Pamplona, Spain
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Rossetti CA, Drake KL, Lawhon SD, Nunes JS, Gull T, Khare S, Adams LG. Systems Biology Analysis of Temporal In vivo Brucella melitensis and Bovine Transcriptomes Predicts host:Pathogen Protein-Protein Interactions. Front Microbiol 2017; 8:1275. [PMID: 28798726 PMCID: PMC5529337 DOI: 10.3389/fmicb.2017.01275] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Accepted: 06/26/2017] [Indexed: 01/13/2023] Open
Abstract
To date, fewer than 200 gene-products have been identified as Brucella virulence factors, and most were characterized individually without considering how they are temporally and coordinately expressed or secreted during the infection process. Here, we describe and analyze the in vivo temporal transcriptional profile of Brucella melitensis during the initial 4 h interaction with cattle. Pathway analysis revealed an activation of the "Two component system" providing evidence that the in vivo Brucella sense and actively regulate their metabolism through the transition to an intracellular lifestyle. Contrarily, other Brucella pathways involved in virulence such as "ABC transporters" and "T4SS system" were repressed suggesting a silencing strategy to avoid stimulation of the host innate immune response very early in the infection process. Also, three flagellum-encoded loci (BMEII0150-0168, BMEII1080-1089, and BMEII1105-1114), the "flagellar assembly" pathway and the cell components "bacterial-type flagellum hook" and "bacterial-type flagellum" were repressed in the tissue-associated B. melitensis, while RopE1 sigma factor, a flagellar repressor, was activated throughout the experiment. These results support the idea that Brucella employ a stealthy strategy at the onset of the infection of susceptible hosts. Further, through systems-level in silico host:pathogen protein-protein interactions simulation and correlation of pathogen gene expression with the host gene perturbations, we identified unanticipated interactions such as VirB11::MAPK8IP1; BtaE::NFKBIA, and 22 kDa OMP precursor::BAD and MAP2K3. These findings are suggestive of new virulence factors and mechanisms responsible for Brucella evasion of the host's protective immune response and the capability to maintain a dormant state. The predicted protein-protein interactions and the points of disruption provide novel insights that will stimulate advanced hypothesis-driven approaches toward revealing a clearer understanding of new virulence factors and mechanisms influencing the pathogenesis of brucellosis.
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Affiliation(s)
- Carlos A Rossetti
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Science, Texas A&M UniversityCollege Station, TX, United States
| | | | - Sara D Lawhon
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Science, Texas A&M UniversityCollege Station, TX, United States
| | - Jairo S Nunes
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Science, Texas A&M UniversityCollege Station, TX, United States
| | - Tamara Gull
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Science, Texas A&M UniversityCollege Station, TX, United States
| | - Sangeeta Khare
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Science, Texas A&M UniversityCollege Station, TX, United States
| | - Leslie G Adams
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Science, Texas A&M UniversityCollege Station, TX, United States
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