1
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Cabello AL, Wells K, Peng W, Feng HQ, Wang J, Meyer DF, Noroy C, Zhao ES, Zhang H, Li X, Chang H, Gomez G, Mao Y, Patrick KL, Watson RO, Russell WK, Yu A, Zhong J, Guo F, Li M, Zhou M, Qian X, Kobayashi KS, Song J, Panthee S, Mechref Y, Ficht TA, Qin QM, de Figueiredo P. Brucella-driven host N-glycome remodeling controls infection. Cell Host Microbe 2024; 32:588-605.e9. [PMID: 38531364 DOI: 10.1016/j.chom.2024.03.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 08/28/2023] [Accepted: 03/06/2024] [Indexed: 03/28/2024]
Abstract
Many powerful methods have been employed to elucidate the global transcriptomic, proteomic, or metabolic responses to pathogen-infected host cells. However, the host glycome responses to bacterial infection remain largely unexplored, and hence, our understanding of the molecular mechanisms by which bacterial pathogens manipulate the host glycome to favor infection remains incomplete. Here, we address this gap by performing a systematic analysis of the host glycome during infection by the bacterial pathogen Brucella spp. that cause brucellosis. We discover, surprisingly, that a Brucella effector protein (EP) Rhg1 induces global reprogramming of the host cell N-glycome by interacting with components of the oligosaccharide transferase complex that controls N-linked protein glycosylation, and Rhg1 regulates Brucella replication and tissue colonization in a mouse model of brucellosis, demonstrating that Brucella exploits the EP Rhg1 to reprogram the host N-glycome and promote bacterial intracellular parasitism, thereby providing a paradigm for bacterial control of host cell infection.
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Affiliation(s)
- Ana-Lucia Cabello
- Department of Veterinary Pathobiology, Texas A&M University, College Station, TX 77843, USA; Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77807, USA
| | - Kelsey Wells
- Christopher S. Bond Life Sciences Center, Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri, Columbia, MO 65211, USA
| | - Wenjing Peng
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, USA
| | - Hui-Qiang Feng
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77807, USA
| | - Junyao Wang
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, USA
| | - Damien F Meyer
- CIRAD, UMR ASTRE, 97170 Petit-Bourg, Guadeloupe, France; ASTRE, University Montpellier, CIRAD, INRAE, Montpellier, France
| | - Christophe Noroy
- CIRAD, UMR ASTRE, 97170 Petit-Bourg, Guadeloupe, France; ASTRE, University Montpellier, CIRAD, INRAE, Montpellier, France
| | - En-Shuang Zhao
- College of Computer Science and Technology, Jilin University, Changchun 130012, China
| | - Hao Zhang
- College of Computer Science and Technology, Jilin University, Changchun 130012, China
| | - Xueqing Li
- College of Computer Science and Technology, Jilin University, Changchun 130012, China
| | - Haowu Chang
- College of Computer Science and Technology, Jilin University, Changchun 130012, China
| | - Gabriel Gomez
- Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL), Texas A&M University, College Station, TX 77843, USA
| | - Yuxin Mao
- Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853-2703, USA
| | - Kristin L Patrick
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77807, USA
| | - Robert O Watson
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77807, USA
| | - William K Russell
- Department of Biochemistry & Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555-0635, USA
| | - Aiying Yu
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, USA
| | - Jieqiang Zhong
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, USA
| | - Fengguang Guo
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77807, USA
| | - Mingqian Li
- Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX 78843, USA
| | - Mingyuan Zhou
- Department of Information, Risk, and Operations Management, Department of Statistics and Data Sciences, The University of Texas at Austin, Austin, TX 78712, USA
| | - Xiaoning Qian
- Department of Electrical and Computer Engineering, Texas A&M University, College Station, TX 78843, USA; TEES-AgriLife Center for Bioinformatics & Genomic Systems Engineering, Texas A&M University, College Station, TX 77843, USA
| | - Koichi S Kobayashi
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77807, USA; Department of Immunology, Hokkaido University Graduate School of Medicine, Sapporo 060-8638, Japan; Hokkaido University, Institute for Vaccine Research and Development (HU-IVReD), Sapporo 060-8638, Japan
| | - Jianxun Song
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77807, USA
| | - Suresh Panthee
- Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, TX 77807, USA
| | - Yehia Mechref
- Department of Chemistry and Biochemistry, Texas Tech University, Lubbock, TX 79409, USA.
| | - Thomas A Ficht
- Department of Veterinary Pathobiology, Texas A&M University, College Station, TX 77843, USA.
| | - Qing-Ming Qin
- Christopher S. Bond Life Sciences Center, Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri, Columbia, MO 65211, USA.
| | - Paul de Figueiredo
- Christopher S. Bond Life Sciences Center, Department of Molecular Microbiology and Immunology, School of Medicine, The University of Missouri, Columbia, MO 65211, USA; Department of Veterinary Pathobiology, The University of Missouri, Columbia, MO 65211, USA.
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2
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Mondal R, Saldaña-Ahuactzi Z, Soria-Bustos J, Schultz A, Yañez-Santos JA, Laguna YM, Cedillo-Ramírez ML, Girón JA. The EcpD Tip Adhesin of the Escherichia coli Common Pilus Mediates Binding of Enteropathogenic E. coli to Extracellular Matrix Proteins. Int J Mol Sci 2022; 23:ijms231810350. [PMID: 36142263 PMCID: PMC9499635 DOI: 10.3390/ijms231810350] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2022] [Revised: 08/04/2022] [Accepted: 08/30/2022] [Indexed: 11/16/2022] Open
Abstract
The attachment of enteropathogenic Escherichia coli (EPEC) to intestinal epithelial cells is facilitated by several adhesins; however, the individual host-cell receptors for pili-mediated adherence have not been fully characterized. In this study, we evaluated the hypothesis that the E. coli common pilus (ECP) tip adhesin protein EcpD mediates attachment of EPEC to several extracellular matrix (ECM) glycoproteins (fibronectin, laminin, collagens I and IV, and mucin). We found that the ΔecpA mutant, which lacks production of the EcpA filament but retains EcpD on the surface, adhered to these glycoproteins below the wild-type levels, while the ΔecpD mutant, which does not display EcpA or EcpD, bound significantly less to these host glycoproteins. In agreement, a purified recombinant EcpD subunit bound significantly more than EcpA to laminin, fibronectin, collagens I and IV, and mucin in a dose-dependent manner. These are compelling data that strongly suggest that ECP-producing EPEC may bind to host ECM glycoproteins and mucins through the tip adhesin protein EcpD. This study highlights the versatility of EPEC to bind to different host proteins and suggests that the interaction of ECP with the host’s ECM glycoproteins may facilitate colonization of the intestinal mucosal epithelium.
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Affiliation(s)
- Rajesh Mondal
- ICMR-Bhopal Memorial Hospital and Research Center, Bhopal 462038, India
| | - Zeus Saldaña-Ahuactzi
- Paul G. Allen School for Global Health, College of Veterinary Medicine, Washington State University, Pullman, WA 99164, USA
| | - Jorge Soria-Bustos
- Facultad de Medicina Mexicali, Universidad Autónoma de Baja California, Mexicali 21100, Mexico
| | - Andrew Schultz
- Department of Microbiology and Molecular Genetics, University of Florida, Gainesville, FL 32611, USA
| | - Jorge A. Yañez-Santos
- Facultad de Estomatología, Benemérita Universidad Autónoma de Puebla, Puebla 72592, Mexico
| | - Ygnacio Martínez Laguna
- Centro de Investigación en Ciencias Microbiológicas, Benemérita Universidad Autónoma de Puebla, Puebla 72592, Mexico
| | - María L. Cedillo-Ramírez
- Centro de Detección Biomolecular, Benemérita Universidad Autónoma de Puebla, Puebla 72592, Mexico
| | - Jorge A. Girón
- Centro de Detección Biomolecular, Benemérita Universidad Autónoma de Puebla, Puebla 72592, Mexico
- Correspondence:
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3
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Mena-Bueno S, Poveda-Urkixo I, Irazoki O, Palacios L, Cava F, Zabalza-Baranguá A, Grilló MJ. Brucella melitensis Wzm/Wzt System: Changes in the Bacterial Envelope Lead to Improved Rev1Δwzm Vaccine Properties. Front Microbiol 2022; 13:908495. [PMID: 35875565 PMCID: PMC9306315 DOI: 10.3389/fmicb.2022.908495] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2022] [Accepted: 05/26/2022] [Indexed: 11/13/2022] Open
Abstract
The lipopolysaccharide (LPS) O-polysaccharide (O-PS) is the main virulence factor in Brucella. After synthesis in the cytoplasmic membrane, O-PS is exported to the periplasm by the Wzm/Wzt system, where it is assembled into a LPS. This translocation also engages a bactoprenol carrier required for further biosynthesis pathways, such as cell wall biogenesis. Targeting O-PS export by blockage holds great potential for vaccine development, but little is known about the biological implications of each Wzm/Wzt moiety. To improve this knowledge and to elucidate its potential application as a vaccine, we constructed and studied wzm/wzt single- and double-deletion mutants, using the attenuated strain Brucella melitensis Rev1 as the parental strain. This allowed us to describe the composition of Brucella peptidoglycan for the first time. We observed that these mutants lack external O-PS yet trigger changes in genetic transcription and in phenotypic properties associated with the outer membrane and cell wall. The three mutants are highly attenuated; unexpectedly, Rev1Δwzm also excels as an immunogenic and effective vaccine against B. melitensis and Brucella ovis in mice, revealing that low persistence is not at odds with efficacy. Rev1Δwzm is attenuated in BeWo trophoblasts, does not infect mouse placentas, and is safe in pregnant ewes. Overall, these attributes and the minimal serological interference induced in sheep make Rev1Δwzm a highly promising vaccine candidate.
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Affiliation(s)
- Sara Mena-Bueno
- Animal Health Department, Instituto de Agrobiotecnología (IdAB, CSIC-Gobierno de Navarra), Pamplona, Spain
- Agronomy, Biotecnology and Food Department, Universidad Pública de Navarra (UPNA), Pamplona, Spain
| | - Irati Poveda-Urkixo
- Animal Health Department, Instituto de Agrobiotecnología (IdAB, CSIC-Gobierno de Navarra), Pamplona, Spain
| | - Oihane Irazoki
- Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| | - Leyre Palacios
- Animal Health Department, Instituto de Agrobiotecnología (IdAB, CSIC-Gobierno de Navarra), Pamplona, Spain
| | - Felipe Cava
- Laboratory for Molecular Infection Medicine Sweden, Department of Molecular Biology, Umeå Centre for Microbial Research, Umeå University, Umeå, Sweden
| | - Ana Zabalza-Baranguá
- Animal Health Department, Instituto de Agrobiotecnología (IdAB, CSIC-Gobierno de Navarra), Pamplona, Spain
| | - María Jesús Grilló
- Animal Health Department, Instituto de Agrobiotecnología (IdAB, CSIC-Gobierno de Navarra), Pamplona, Spain
- *Correspondence: María Jesús Grilló,
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4
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Poveda-Urkixo I, Ramírez GA, Grilló MJ. Kinetics of Placental Infection by Different Smooth Brucella Strains in Mice. Pathogens 2022; 11:pathogens11030279. [PMID: 35335603 PMCID: PMC8955611 DOI: 10.3390/pathogens11030279] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2022] [Revised: 02/16/2022] [Accepted: 02/20/2022] [Indexed: 01/18/2023] Open
Abstract
Abortion and reproductive failures induced by Brucella are the main symptoms of animal brucellosis. Laboratory animal models are essential tools of research to study the Brucella pathogenesis before experimentation in natural hosts. To extend the existing knowledge, we studied B. melitensis 16M (virulent) and Rev1 (attenuated) as well as B. suis bv2 infections in pregnant mice. Here, we report new information about kinetics of infection (in spleens, blood, placentas, vaginal shedding, and foetuses), serum cytokine profiles, and histopathological features in placentas and the litter throughout mice pregnancy. Both B. melitensis strains showed a marked placental tropism and reduced viability of pups (mainly in 16M infections), which was preceded by an intense Th1-immune response during placental development. In contrast, B. suis bv2 displayed lower placental tropism, mild proinflammatory immune response, and scarce bacterial transmission to the litter, thus allowing foetal viability. Overall, our studies revealed three different smooth Brucella patterns of placental and foetal pathogenesis in mice, providing a useful animal model for experimental brucellosis.
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Affiliation(s)
- Irati Poveda-Urkixo
- Instituto de Agrobiotecnología (IdAB, CSIC-Gobierno de Navarra), Avda. Pamplona 123, 31192 Mutilva, Spain;
| | - Gustavo A. Ramírez
- Departamento de Sanidad Animal, Universidad de Lleida, 25198 Lleida, Spain;
| | - María-Jesús Grilló
- Instituto de Agrobiotecnología (IdAB, CSIC-Gobierno de Navarra), Avda. Pamplona 123, 31192 Mutilva, Spain;
- Correspondence:
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5
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Bauer S, Zhang F, Linhardt RJ. Implications of Glycosaminoglycans on Viral Zoonotic Diseases. Diseases 2021; 9:85. [PMID: 34842642 PMCID: PMC8628766 DOI: 10.3390/diseases9040085] [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: 10/13/2021] [Revised: 11/10/2021] [Accepted: 11/15/2021] [Indexed: 11/21/2022] Open
Abstract
Zoonotic diseases are infectious diseases that pass from animals to humans. These include diseases caused by viruses, bacteria, fungi, and parasites and can be transmitted through close contact or through an intermediate insect vector. Many of the world's most problematic zoonotic diseases are viral diseases originating from animal spillovers. The Spanish influenza pandemic, Ebola outbreaks in Africa, and the current SARS-CoV-2 pandemic are thought to have started with humans interacting closely with infected animals. As the human population grows and encroaches on more and more natural habitats, these incidents will only increase in frequency. Because of this trend, new treatments and prevention strategies are being explored. Glycosaminoglycans (GAGs) are complex linear polysaccharides that are ubiquitously present on the surfaces of most human and animal cells. In many infectious diseases, the interactions between GAGs and zoonotic pathogens correspond to the first contact that results in the infection of host cells. In recent years, researchers have made progress in understanding the extraordinary roles of GAGs in the pathogenesis of zoonotic diseases, suggesting potential therapeutic avenues for using GAGs in the treatment of these diseases. This review examines the role of GAGs in the progression, prevention, and treatment of different zoonotic diseases caused by viruses.
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Affiliation(s)
- Sarah Bauer
- Department of Chemistry and Chemical Biology, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180, USA;
| | - Fuming Zhang
- Department of Chemistry and Chemical Biology, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180, USA;
- Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
| | - Robert J. Linhardt
- Department of Chemistry and Chemical Biology, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180, USA;
- Department of Chemical and Biological Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
- Departments of Biological Science, Biomedical Engineering, Center for Biotechnology and Interdisciplinary Studies, Rensselaer Polytechnic Institute, Troy, NY 12180, USA
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6
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Li X, Wu Q, Zhang X, Li C, Zhang D, Li G, Zhang Y, Zhao Y, Shi Z, Wang W, Li F. Whole-Genome Resequencing to Study Brucellosis Susceptibility in Sheep. Front Genet 2021; 12:653927. [PMID: 34306007 PMCID: PMC8297390 DOI: 10.3389/fgene.2021.653927] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2021] [Accepted: 06/14/2021] [Indexed: 02/05/2023] Open
Abstract
Brucellosis is a zoonotic disease and a major public health problem. However, the genetic mechanism of brucellosis in sheep remains unclear. In this study, serum samples were collected from 6,358 sheep from the F2 population (Dorper sheep ♂ × Hu sheep ♀), and antibody levels were continuously measured at 14 days and 1, 2, 3, 4, 5, 6, 7, 8, 9, and 10 months after administration of brucellosis vaccine. Finally, 19 brucellosis-resistant group (BRG) sheep and 22 brucellosis-susceptible group sheep (BSG) were screened for whole-genome sequencing. Using the fixation index, Fisher’s exact test, and chi-square test, a total of 205 candidate SNP sites were identified. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis suggested that 138 candidate genes were significantly enriched in adherens junction (CTNNA3, PARD3, and PTPRM), cell adhesion molecules (NLGN1, CNTNAP2, NCAM1, and PTPRM), salivary secretion (LOC101102109, PRKG1, and ADCY2), and hippo signaling pathway (CTNNA3, YAP1, and PARD3). These findings provide valuable molecular markers for brucellosis resistance breeding in sheep and novel insights into the genetic mechanism of brucellosis resistance.
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Affiliation(s)
- Xiaolong Li
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Qingmin Wu
- College of Veterinary Medicine, China Agricultural University, Beijing, China
| | - Xiaoxue Zhang
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China.,Engineering Laboratory of Sheep Breeding and Reproduction Biotechnology in Gansu Province, Minqin, China
| | - Chong Li
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China.,Engineering Laboratory of Sheep Breeding and Reproduction Biotechnology in Gansu Province, Minqin, China
| | - Deyin Zhang
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Guoze Li
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Yukun Zhang
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Yuan Zhao
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Zhaoguo Shi
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Weimin Wang
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China
| | - Fadi Li
- College of Animal Science and Technology, Gansu Agricultural University, Lanzhou, China.,Engineering Laboratory of Sheep Breeding and Reproduction Biotechnology in Gansu Province, Minqin, China.,The State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou, China
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7
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Zai X, Yin Y, Guo F, Yang Q, Li R, Li Y, Zhang J, Xu J, Chen W. Screening of potential vaccine candidates against pathogenic Brucella spp. using compositive reverse vaccinology. Vet Res 2021; 52:75. [PMID: 34078437 PMCID: PMC8170439 DOI: 10.1186/s13567-021-00939-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/09/2020] [Accepted: 03/04/2021] [Indexed: 11/25/2022] Open
Abstract
Brucella spp. are Gram-negative, facultative intracellular bacteria that cause brucellosis in humans and various animals. The threat of brucellosis has increased, yet currently available live attenuated vaccines still have drawbacks. Therefore, subunit vaccines, produced using protein antigens and having the advantage of being safe, cost-effective and efficacious, are urgently needed. In this study, we used core proteome analysis and a compositive RV methodology to screen potential broad-spectrum antigens against 213 pathogenic strains of Brucella spp. with worldwide geographic distribution. Candidate proteins were scored according to six biological features: subcellular localization, antigen similarity, antigenicity, mature epitope density, virulence, and adhesion probability. In the RV analysis, a total 32 candidate antigens were picked out. Of these, three proteins were selected for assessment of immunogenicity and preliminary protection in a mouse model: outer membrane protein Omp19 (used as a positive control), type IV secretion system (T4SS) protein VirB8, and type I secretion system (T1SS) protein HlyD. These three antigens with a high degree of conservation could induce specific humoral and cellular immune responses. Omp19, VirB8 and HlyD could substantially reduce the organ bacterial load of B. abortus S19 in mice and provide varying degrees of protection. In this study, we demonstrated the effectiveness of this unique strategy for the screening of potential broad-spectrum antigens against Brucella. Further evaluation is needed to identify the levels of protection conferred by the vaccine antigens against wild-type pathogenic Brucella species challenge.
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Affiliation(s)
- Xiaodong Zai
- Laboratory of Vaccine and Antibody Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Ying Yin
- Laboratory of Vaccine and Antibody Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Fengyu Guo
- Laboratory of Vaccine and Antibody Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Qiaoling Yang
- Laboratory of Vaccine and Antibody Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Ruihua Li
- Laboratory of Vaccine and Antibody Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Yaohui Li
- Laboratory of Vaccine and Antibody Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Jun Zhang
- Laboratory of Vaccine and Antibody Engineering, Beijing Institute of Biotechnology, Beijing, China
| | - Junjie Xu
- Laboratory of Vaccine and Antibody Engineering, Beijing Institute of Biotechnology, Beijing, China.
| | - Wei Chen
- Laboratory of Vaccine and Antibody Engineering, Beijing Institute of Biotechnology, Beijing, China.
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8
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Bialer MG, Ferrero MC, Delpino MV, Ruiz-Ranwez V, Posadas DM, Baldi PC, Zorreguieta A. Adhesive Functions or Pseudogenization of Type Va Autotransporters in Brucella Species. Front Cell Infect Microbiol 2021; 11:607610. [PMID: 33987105 PMCID: PMC8111173 DOI: 10.3389/fcimb.2021.607610] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2020] [Accepted: 04/01/2021] [Indexed: 01/18/2023] Open
Abstract
Adhesion to host cells is a key step for successful infection of many bacterial pathogens and may define tropism to different host tissues. To do so, bacteria display adhesins on their surfaces. Brucella is an intracellular pathogen capable of proliferating in a wide variety of cell types. It has been described that BmaC, a large protein that belongs to the classical (type Va) autotransporter family, is required for efficient adhesion of Brucella suis strain 1330 to epithelial cells and fibronectin. Here we show that B. suis 1330 harbors two other type Va autotransporters (BmaA and BmaB), which, although much smaller, share significant sequence similarities with BmaC and contain the essential domains to mediate proper protein translocation to the bacterial surface. Gain and loss of function studies indicated that BmaA, BmaB, and BmaC contribute, to a greater or lesser degree, to adhesion of B. suis 1330 to different cells such as synovial fibroblasts, osteoblasts, trophoblasts, and polarized epithelial cells as well as to extracellular matrix components. It was previously shown that BmaC localizes to a single bacterial pole. Interestingly, we observed here that, similar to BmaC, the BmaB adhesin is localized mostly at a single cell pole, reinforcing the hypothesis that Brucella displays an adhesive pole. Although Brucella species have strikingly similar genomes, they clearly differ in their host preferences. Mainly, the differences identified between species appear to be at loci encoding surface proteins. A careful in silico analysis of the putative type Va autotransporter orthologues from several Brucella strains showed that the bmaB locus from Brucella abortus and both, the bmaA and bmaC loci from Brucella melitensis are pseudogenes in all strains analyzed. Results reported here evidence that all three autotransporters play a role in the adhesion properties of B. suis 1330. However, Brucella spp. exhibit extensive variations in the repertoire of functional adhesins of the classical autotransporter family that can be displayed on the bacterial surface, making them an interesting target for future studies on host preference and tropism.
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Affiliation(s)
- Magalí G Bialer
- Fundación Instituto Leloir (FIL), IIBBA (CONICET-FIL), Buenos Aires, Argentina
| | - Mariana C Ferrero
- Facultad de Farmacia y Bioquímica, Cátedra de Inmunología, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Estudios de la Inmunidad Humoral (IDEHU), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - M Victoria Delpino
- Instituto de Inmunología, Genética y Metabolismo (INIGEM), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | | | - Diana M Posadas
- Fundación Instituto Leloir (FIL), IIBBA (CONICET-FIL), Buenos Aires, Argentina
| | - Pablo C Baldi
- Facultad de Farmacia y Bioquímica, Cátedra de Inmunología, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Estudios de la Inmunidad Humoral (IDEHU), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Angeles Zorreguieta
- Fundación Instituto Leloir (FIL), IIBBA (CONICET-FIL), Buenos Aires, Argentina.,Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires, Argentina
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9
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Bialer MG, Sycz G, Muñoz González F, Ferrero MC, Baldi PC, Zorreguieta A. Adhesins of Brucella: Their Roles in the Interaction with the Host. Pathogens 2020; 9:E942. [PMID: 33198223 PMCID: PMC7697752 DOI: 10.3390/pathogens9110942] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2020] [Revised: 11/03/2020] [Accepted: 11/05/2020] [Indexed: 01/30/2023] Open
Abstract
A central aspect of Brucella pathogenicity is its ability to invade, survive, and replicate in diverse phagocytic and non-phagocytic cell types, leading to chronic infections and chronic inflammatory phenomena. Adhesion to the target cell is a critical first step in the invasion process. Several Brucella adhesins have been shown to mediate adhesion to cells, extracellular matrix components (ECM), or both. These include the sialic acid-binding proteins SP29 and SP41 (binding to erythrocytes and epithelial cells, respectively), the BigA and BigB proteins that contain an Ig-like domain (binding to cell adhesion molecules in epithelial cells), the monomeric autotransporters BmaA, BmaB, and BmaC (binding to ECM components, epithelial cells, osteoblasts, synoviocytes, and trophoblasts), the trimeric autotransporters BtaE and BtaF (binding to ECM components and epithelial cells) and Bp26 (binding to ECM components). An in vivo role has also been shown for the trimeric autotransporters, as deletion mutants display decreased colonization after oral and/or respiratory infection in mice, and it has also been suggested for BigA and BigB. Several adhesins have shown unipolar localization, suggesting that Brucella would express an adhesive pole. Adhesin-based vaccines may be useful to prevent brucellosis, as intranasal immunization in mice with BtaF conferred high levels of protection against oral challenge with B. suis.
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Affiliation(s)
- Magalí G. Bialer
- Fundación Instituto Leloir (FIL), IIBBA (CONICET-FIL), Buenos Aires 1405, Argentina; (M.G.B.); (G.S.)
| | - Gabriela Sycz
- Fundación Instituto Leloir (FIL), IIBBA (CONICET-FIL), Buenos Aires 1405, Argentina; (M.G.B.); (G.S.)
| | - Florencia Muñoz González
- Cátedra de Inmunología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires 1113, Argentina; (F.M.G.); (M.C.F.)
- Instituto de Estudios de la Inmunidad Humoral (IDEHU), CONICET-Universidad de Buenos Aires, Buenos Aires 1113, Argentina
| | - Mariana C. Ferrero
- Cátedra de Inmunología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires 1113, Argentina; (F.M.G.); (M.C.F.)
- Instituto de Estudios de la Inmunidad Humoral (IDEHU), CONICET-Universidad de Buenos Aires, Buenos Aires 1113, Argentina
| | - Pablo C. Baldi
- Cátedra de Inmunología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires 1113, Argentina; (F.M.G.); (M.C.F.)
- Instituto de Estudios de la Inmunidad Humoral (IDEHU), CONICET-Universidad de Buenos Aires, Buenos Aires 1113, Argentina
| | - Angeles Zorreguieta
- Fundación Instituto Leloir (FIL), IIBBA (CONICET-FIL), Buenos Aires 1405, Argentina; (M.G.B.); (G.S.)
- Departamento de Química Biológica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Buenos Aires 1428, Argentina
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10
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Teng C, Lin C, Huang F, Xing X, Chen S, Ye L, Azevedo HS, Xu C, Wu Z, Chen Z, He W. Intracellular codelivery of anti-inflammatory drug and anti-miR 155 to treat inflammatory disease. Acta Pharm Sin B 2020; 10:1521-1533. [PMID: 32963947 PMCID: PMC7488359 DOI: 10.1016/j.apsb.2020.06.005] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/18/2020] [Accepted: 05/25/2020] [Indexed: 12/27/2022] Open
Abstract
Atherosclerosis (AS) is a lipid-driven chronic inflammatory disease occurring at the arterial subendothelial space. Macrophages play a critical role in the initiation and development of AS. Herein, targeted codelivery of anti-miR 155 and anti-inflammatory baicalein is exploited to polarize macrophages toward M2 phenotype, inhibit inflammation and treat AS. The codelivery system consists of a carrier-free strategy (drug-delivering-drug, DDD), fabricated by loading anti-miR155 on baicalein nanocrystals, named as baicalein nanorods (BNRs), followed by sialic acid coating to target macrophages. The codelivery system, with a diameter of 150 nm, enables efficient intracellular delivery of anti-miR155 and polarizes M1 to M2, while markedly lowers the level of inflammatory factors in vitro and in vivo. In particular, intracellular fate assay reveals that the codelivery system allows for sustained drug release over time after internalization. Moreover, due to prolonged blood circulation and improved accumulation at the AS plaque, the codelivery system significantly alleviates AS in animal model by increasing the artery lumen diameter, reducing blood pressure, promoting M2 polarization, inhibiting secretion of inflammatory factors and decreasing blood lipids. Taken together, the codelivery could potentially be used to treat vascular inflammation.
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Affiliation(s)
- Chao Teng
- School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Chenshi Lin
- School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Feifei Huang
- School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Xuyang Xing
- School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Shenyu Chen
- School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
| | - Ling Ye
- School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China
| | - Helena S. Azevedo
- School of Engineering and Materials Science, Institute of Bioengineering, University of London, London E1 4NS, UK
| | - Chenjie Xu
- Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Zhengfeng Wu
- Key Laboratory of Modern Preparation of TCM, Ministry of Education, Jiangxi University of Traditional Chinese Medicine, Nanchang 330004, China
| | - Zhongjian Chen
- Shanghai Skin Disease Hospital, Tongji University School of Medicine, Shanghai 200443, China
| | - Wei He
- School of Pharmacy, China Pharmaceutical University, Nanjing 210009, China
- Shanghai Skin Disease Hospital, Tongji University School of Medicine, Shanghai 200443, China
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11
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Gómez LA, Alvarez FI, Molina RE, Soto-Shara R, Daza-Castro C, Flores MR, León Y, Oñate AA. A Zinc-Dependent Metalloproteinase of Brucella abortus Is Required in the Intracellular Adaptation of Macrophages. Front Microbiol 2020; 11:1586. [PMID: 32765455 PMCID: PMC7379133 DOI: 10.3389/fmicb.2020.01586] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2020] [Accepted: 06/17/2020] [Indexed: 01/19/2023] Open
Abstract
Brucella abortus is a pathogen that survives in macrophages. Several virulence factors participate in this process, including the open reading frame (ORF) BAB1_0270 codifying for a zinc-dependent metalloproteinase (ZnMP). Here, its contribution in the intracellular adaptation of B. abortus was analyzed by infecting RAW264.7 macrophages with the mutant B. abortus Δ270 strain. Results showed that this ZnMP did not participated in either the adherence or the initial intracellular traffic of B. abortus in macrophages. Nevertheless, its deletion significantly increased the co-localization of B. abortus Δ270 with phagolysosomal cathepsin D and reduced its co-localization with calnexin present in endoplasmic reticulum (RE)-derived vesicles. Although B. abortus Δ270 showed an upregulated expression of genes involved in virulence (vjbR, hutC, bvrR, virB1), it was insufficient to reach a successful intracellular replication within macrophages. Furthermore, its attenuation favored in macrophages infected the production of high levels of cytokines (TNF-α and IL-6) and co-stimulatory proteins (CD80 and CD86), signals required in T cell activation. Finally, its deletion significantly reduced the ability of B. abortus Δ270 to adapt, grow and express several virulence factors under acidic conditions. Based on these results, and considering that this ZnMP has homology with ImmA/IrrE proteases, we discuss its role in the virulence of this pathogen, concluding that ZnMP is required in the intracellular adaptation of B. abortus 2308 during the infection of macrophages.
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Affiliation(s)
| | | | | | | | | | | | | | - Angel A. Oñate
- Laboratory of Molecular Immunology, Department of Microbiology, Faculty of Biological Sciences, University of Concepción, Concepción, Chile
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12
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ElTahir Y, Al-Araimi A, Nair RR, Autio KJ, Tu H, Leo JC, Al-Marzooqi W, Johnson EH. Binding of Brucella protein, Bp26, to select extracellular matrix molecules. BMC Mol Cell Biol 2019; 20:55. [PMID: 31783731 PMCID: PMC6884894 DOI: 10.1186/s12860-019-0239-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2018] [Accepted: 11/19/2019] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Brucella is a facultative intracellular pathogen responsible for zoonotic disease brucellosis. Little is known about the molecular basis of Brucella adherence to host cells. In the present study, the possible role of Bp26 protein as an adhesin was explored. The ability of Brucella protein Bp26 to bind to extracellular matrix (ECM) proteins was determined by enzyme-linked immunosorbent assay (ELISA) and biolayer interferometry (BLI). RESULTS ELISA experiments showed that Bp26 bound in a dose-dependent manner to both immobilized type I collagen and vitronectin. Bp26 bound weakly to soluble fibronectin but did not bind to immobilized fibronectin. No binding to laminin was detected. Biolayer interferometry showed high binding affinity of Bp26 to immobilized type I collagen and no binding to fibronectin or laminin. Mapping of Bp26 antigenic epitopes by biotinylated overlapping peptides spanning the entire sequence of Bp26 using anti Bp26 mouse serum led to the identification of five linear epitopes. Collagen and vitronectin bound to peptides from several regions of Bp26, with many of the binding sites for the ligands overlapping. The strongest binding for anti-Bp26 mouse serum, collagen and vitronectin was to the peptides at the C-terminus of Bp26. Fibronectin did not bind to any of the peptides, although it bound to the whole Bp26 protein. CONCLUSIONS Our results highlight the possible role of Bp26 protein in the adhesion process of Brucella to host cells through ECM components. This study revealed that Bp26 binds to both immobilized and soluble type I collagen and vitronectin. It also binds to soluble but not immobilized fibronectin. However, Bp26 does not bind to laminin. These are novel findings that offer insight into understanding the interplay between Brucella and host target cells, which may aid in future identification of a new target for diagnosis and/or vaccine development and prevention of brucellosis.
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Affiliation(s)
- Yasmin ElTahir
- Department of Animal & Veterinary Sciences, Sultan Qaboos University. College of Agricultural & Marine Sciences, P.O.box 34. 123 Alkhod, Muscat, Sultanate of Oman.
| | - Amna Al-Araimi
- Department of Animal & Veterinary Sciences, Sultan Qaboos University. College of Agricultural & Marine Sciences, P.O.box 34. 123 Alkhod, Muscat, Sultanate of Oman
| | - Remya R Nair
- Department of Animal & Veterinary Sciences, Sultan Qaboos University. College of Agricultural & Marine Sciences, P.O.box 34. 123 Alkhod, Muscat, Sultanate of Oman
| | - Kaija J Autio
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, FI-90014, Oulu, Finland
| | - Hongmin Tu
- Faculty of Biochemistry and Molecular Medicine, University of Oulu, FI-90014, Oulu, Finland
| | - Jack C Leo
- Section for Genetics and Evolutionary Biology, Department of Biosciences, University of Oslo, 0361, Oslo, Norway.,Department of Biosciences, School of Science & Technology, Nottingham Trent University, Nottingham, NG1 4FQ, UK
| | - Waleed Al-Marzooqi
- Department of Animal & Veterinary Sciences, Sultan Qaboos University. College of Agricultural & Marine Sciences, P.O.box 34. 123 Alkhod, Muscat, Sultanate of Oman
| | - Eugene H Johnson
- Department of Animal & Veterinary Sciences, Sultan Qaboos University. College of Agricultural & Marine Sciences, P.O.box 34. 123 Alkhod, Muscat, Sultanate of Oman
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13
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Muñoz González F, Sycz G, Alonso Paiva IM, Linke D, Zorreguieta A, Baldi PC, Ferrero MC. The BtaF Adhesin Is Necessary for Full Virulence During Respiratory Infection by Brucella suis and Is a Novel Immunogen for Nasal Vaccination Against Brucella Infection. Front Immunol 2019; 10:1775. [PMID: 31402921 PMCID: PMC6676368 DOI: 10.3389/fimmu.2019.01775] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2019] [Accepted: 07/15/2019] [Indexed: 01/18/2023] Open
Abstract
Brucella enters their hosts mostly through mucosae from where it spreads systemically. Adhesion to extracellular matrix (ECM) components or to host cells is important for the infectious process, and is mediated by several adhesins, including the BtaF trimeric autotransporter. Although Th1 responses and gamma interferon (IFN-γ) are important for protection, antibodies able to block adhesions might also contribute to prevent Brucella infection. We evaluated the importance of BtaF for respiratory Brucella infection, and characterized the immune response and protection from mucosal challenge induced by nasal vaccination with recombinant BtaF. While lung CFU numbers did not differ at day 1 p.i. between mice intratracheally inoculated with B. suis M1330 (wild type) and those receiving a ΔbtaF mutant, they were reduced in the latter group at 7 and 30 days p.i. For vaccination studies the BtaF passenger domain was engineered and expressed as a soluble trimeric protein. Mice were immunized by the nasal route with BtaF or saline (control group) plus the mucosal adjuvant c-di-AMP. Specific anti-BtaF antibodies (IgG and IgA) were increased in serum, including a mixed IgG2a/IgG1 response. In vitro, these antibodies reduced bacterial adhesion to A549 alveolar epithelial cells. Specific IgA antibodies were also increased in several mucosae. Spleen cells from BtaF immunized mice significantly increased their IL-2, IL-5, IL-17, and IFN-γ secretion upon antigen stimulation. In cervical draining lymph nodes, antigen-experienced CD4+ T cells were maintained mainly as central memory cells. A BtaF-specific delayed-type hypersensitivity response was detected in BtaF immunized mice. Lung cells from the latter produced high levels of IFN-γ upon antigen stimulation. Although nasal immunization with BtaF did not protect mice against B. suis respiratory challenge, it conferred significant protection from intragastric challenge; the splenic load of B. suis was reduced by 3.28 log CFU in immunized mice. This study shows that nasal vaccination with BtaF+c-di-AMP protects against intragastric challenge with B. suis by inducing local and systemic antibody responses, central memory CD4+ T cells and strong Th1 responses. Therefore, although BtaF vaccination did not protect from B. suis respiratory infection, this adhesin constitutes a promising immunogen against mucosal B. suis infection.
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Affiliation(s)
- Florencia Muñoz González
- Cátedra de Inmunología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Estudios de la Inmunidad Humoral (IDEHU), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Gabriela Sycz
- Fundación Instituto Leloir, IIBBA-CONICET, Buenos Aires, Argentina
| | - Iván M Alonso Paiva
- Cátedra de Inmunología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Estudios de la Inmunidad Humoral (IDEHU), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Dirk Linke
- Centre for Ecological and Evolutionary Synthesis, University of Oslo, Oslo, Norway
| | | | - Pablo C Baldi
- Cátedra de Inmunología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Estudios de la Inmunidad Humoral (IDEHU), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
| | - Mariana C Ferrero
- Cátedra de Inmunología, Facultad de Farmacia y Bioquímica, Universidad de Buenos Aires, Buenos Aires, Argentina.,Instituto de Estudios de la Inmunidad Humoral (IDEHU), CONICET-Universidad de Buenos Aires, Buenos Aires, Argentina
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14
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A Role for the VPS Retromer in Brucella Intracellular Replication Revealed by Genomewide siRNA Screening. mSphere 2019; 4:4/3/e00380-19. [PMID: 31243080 PMCID: PMC6595151 DOI: 10.1128/msphere.00380-19] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
Brucella, the agent causing brucellosis, is a major zoonotic pathogen with worldwide distribution. Brucella resides and replicates inside infected host cells in membrane-bound compartments called Brucella-containing vacuoles (BCVs). Following uptake, Brucella resides in endosomal BCVs (eBCVs) that gradually mature from early to late endosomal features. Through a poorly understood process that is key to the intracellular lifestyle of Brucella, the eBCV escapes fusion with lysosomes by transitioning to the replicative BCV (rBCV), a replicative niche directly connected to the endoplasmic reticulum (ER). Despite the notion that this complex intracellular lifestyle must depend on a multitude of host factors, a holistic view on which of these components control Brucella cell entry, trafficking, and replication is still missing. Here we used a systematic cell-based small interfering RNA (siRNA) knockdown screen in HeLa cells infected with Brucella abortus and identified 425 components of the human infectome for Brucella infection. These include multiple components of pathways involved in central processes such as the cell cycle, actin cytoskeleton dynamics, or vesicular trafficking. Using assays for pathogen entry, knockdown complementation, and colocalization at single-cell resolution, we identified the requirement of the VPS retromer for Brucella to escape the lysosomal degradative pathway and to establish its intracellular replicative niche. We thus validated the VPS retromer as a novel host factor critical for Brucella intracellular trafficking. Further, our genomewide data shed light on the interplay between central host processes and the biogenesis of the Brucella replicative niche.IMPORTANCE With >300,000 new cases of human brucellosis annually, Brucella is regarded as one of the most important zoonotic bacterial pathogens worldwide. The agent causing brucellosis resides inside host cells within vacuoles termed Brucella-containing vacuoles (BCVs). Although a few host components required to escape the degradative lysosomal pathway and to establish the ER-derived replicative BCV (rBCV) have already been identified, the global understanding of this highly coordinated process is still partial, and many factors remain unknown. To gain deeper insight into these fundamental questions, we performed a genomewide RNA interference (RNAi) screen aiming at discovering novel host factors involved in the Brucella intracellular cycle. We identified 425 host proteins that contribute to Brucella cellular entry, intracellular trafficking, and replication. Together, this study sheds light on previously unknown host pathways required for the Brucella infection cycle and highlights the VPS retromer components as critical factors for the establishment of the Brucella intracellular replicative niche.
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15
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Waldrop SG, Sriranganathan N. Intracellular invasion and survival of Brucella neotomae, another possible zoonotic Brucella species. PLoS One 2019; 14:e0213601. [PMID: 30943213 PMCID: PMC6447175 DOI: 10.1371/journal.pone.0213601] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2018] [Accepted: 02/25/2019] [Indexed: 12/17/2022] Open
Abstract
In 1967, Brucella neotomae was first isolated from Neotoma lepida, the dessert wood rat, in Utah. With little infection data since its discovery, the zoonotic potential of this Brucella species is largely unknown. Recent reports of isolation from human cerebrospinal fluid, along with current literature suggest that B. neotomae has the ability to infect various hosts and cell types. In this report we extend the knowledge of B. neotomae ATCC 23459’s intracellular invasion and survival abilities to a variety of cell lines through gentamicin protection assays. Some of the phagocytic and epithelial cell lines from various mammalian species represent characteristics of some cell types that could be encountered by Brucella in potential hosts. It was found that B. neotomae ATCC 23459 exhibits generally lower intracellular bacterial CFUs compared to the mouse-passaged strain of B. neotomae ATCC 23459, B. suis 1330, and B. abortus 2308. Ultimately, these observations provide a small piece of the puzzle in the investigation of the breadth of B. neotomae’s pathogenic potential.
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Affiliation(s)
- Steven Grant Waldrop
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, United States of America
| | - Nammalwar Sriranganathan
- Department of Biomedical Sciences and Pathobiology, Virginia-Maryland College of Veterinary Medicine, Virginia Tech, Blacksburg, Virginia, United States of America
- * E-mail:
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16
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Bacterial sialoglycosidases in Virulence and Pathogenesis. Pathogens 2019; 8:pathogens8010039. [PMID: 30909660 PMCID: PMC6471121 DOI: 10.3390/pathogens8010039] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2019] [Revised: 03/18/2019] [Accepted: 03/19/2019] [Indexed: 12/12/2022] Open
Abstract
Human oral microbiome and dysbiotic infections have been recently evidently identified. One of the major reasons for such dysbiosis is impairment of the immune system. Periodontitis is a chronic inflammatory disease affecting the tissues that surround and support the teeth. In the United States., approximately 65 million people are affected by this condition. Its occurrence is also associated with many important systemic diseases such as cardiovascular disease, rheumatoid arthritis, and Alzheimer’s disease. Among the most important etiologies of periodontitis is Porphyromonas gingivalis, a keystone bacterial pathogen. Keystone pathogens can orchestrate inflammatory disease by remodeling a normally benign microbiota causing imbalance between normal and pathogenic microbiota (dysbiosis). The important characteristics of P. gingivalis causing dysbiosis are its virulence factors which cause effective subversion of host defenses to its advantage allowing other pathogens to grow. Some of the mechanisms involved in these processes are still not well-understood. However, various microbial strategies target host sialoglycoproteins for immune dysregulation. In addition, the enzymes that break down sialoglycoproteins and sialoglycans are the “sialoglycoproteases”, resulting in exposed terminal sialic acid. This process could lead to pathogen-toll like receptor (TLR) interactions mediated through sialic acid receptor ligand mechanisms. Assessing the function of P. gingivalis sialoglycoproteases, could pave the way to designing carbohydrate analogues and sialic acid mimetics to serve as drug targets.
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17
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Amjadi O, Rafiei A, Mardani M, Zafari P, Zarifian A. A review of the immunopathogenesis of Brucellosis. Infect Dis (Lond) 2019; 51:321-333. [PMID: 30773082 DOI: 10.1080/23744235.2019.1568545] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Brucellosis, caused by the intracellular pathogens Brucella, is one of the major zoonotic infections. Considering the economic burden, its prevalence has been a health concern especially in endemic regions. Brucella is able to survive and replicate within host cells by expressing different virulence factors and using various strategies to avoid the host's immune response. This leads to progression of the disease from an acute phase to chronic brucellosis. Exploration of genetic variations has confirmed the expected influence of gene polymorphisms on susceptibility and resistance to brucellosis of humans. Since there is no approved human vaccine and treatment is uncertain with risk of relapse, it is important to increase knowledge about pathogenesis, diagnosis and treatment of brucellosis in order to manage and control this infection, especially in endemic regions.
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Affiliation(s)
- Omolbanin Amjadi
- a Student Research Committee, Department of Immunology, School of Medicine , Mazandaran University of Medical Sciences , Sari , Iran
| | - Alireza Rafiei
- b Department of Immunology, School of Medicine , Mazandaran University of Medical Sciences , Sari , Iran
| | - Masoud Mardani
- c Infectious Diseases and Tropical Medicine Research Center , Shahid Beheshti University of Medical Sciences , Tehran , Iran
| | - Parisa Zafari
- a Student Research Committee, Department of Immunology, School of Medicine , Mazandaran University of Medical Sciences , Sari , Iran.,b Department of Immunology, School of Medicine , Mazandaran University of Medical Sciences , Sari , Iran
| | - Ahmadreza Zarifian
- d Infectious Disease Research Group, Student Research Committee, Medical School , Mashhad University of Medical Sciences , Mashhad , Iran
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18
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Poncin K, Gillet S, De Bolle X. Learning from the master: targets and functions of the CtrA response regulator in Brucella abortus and other alpha-proteobacteria. FEMS Microbiol Rev 2018; 42:500-513. [PMID: 29733367 DOI: 10.1093/femsre/fuy019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 05/02/2018] [Indexed: 12/27/2022] Open
Abstract
The α-proteobacteria are a fascinating group of free-living, symbiotic and pathogenic organisms, including the Brucella genus, which is responsible for a worldwide zoonosis. One common feature of α-proteobacteria is the presence of a conserved response regulator called CtrA, first described in the model bacterium Caulobacter crescentus, where it controls gene expression at different stages of the cell cycle. Here, we focus on Brucella abortus and other intracellular α-proteobacteria in order to better assess the potential role of CtrA in the infectious context. Comparative genomic analyses of the CtrA control pathway revealed the conservation of specific modules, as well as the acquisition of new factors during evolution. The comparison of CtrA regulons also suggests that specific clades of α-proteobacteria acquired distinct functions under its control, depending on the essentiality of the transcription factor. Other CtrA-controlled functions, for instance motility and DNA repair, are proposed to be more ancestral. Altogether, these analyses provide an interesting example of the plasticity of a regulation network, subject to the constraints of inherent imperatives such as cell division and the adaptations to diversified environmental niches.
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Affiliation(s)
- Katy Poncin
- URBM-Biology, Université de Namur, Unité de recherche en biologie moléculaire, Belgium
| | - Sébastien Gillet
- URBM-Biology, Université de Namur, Unité de recherche en biologie moléculaire, Belgium
| | - Xavier De Bolle
- URBM-Biology, Université de Namur, Unité de recherche en biologie moléculaire, Belgium
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19
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D'Orazio G, Munizza L, Zampolli J, Forcella M, Zoia L, Fusi P, Di Gennaro P, La Ferla B. Cellulose nanocrystals are effective in inhibiting host cell bacterial adhesion. J Mater Chem B 2017; 5:7018-7020. [DOI: 10.1039/c7tb01923h] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The use of cellulose nanocrystals (CNCs) as a biomaterial able to inhibit host cell bacterial adhesion is described. Pre-incubation ofE. coliwith a suspension of CNCs affords a significant reduction of bacterial adhesion to intestinal cell monolayer HT29, without exerting a bactericidal effect.
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Affiliation(s)
- G. D'Orazio
- Department of Biotechnology and Biosciences
- University of Milano-Bicocca
- 20126 Milano
- Italy
| | - L. Munizza
- Department of Biotechnology and Biosciences
- University of Milano-Bicocca
- 20126 Milano
- Italy
| | - J. Zampolli
- Department of Biotechnology and Biosciences
- University of Milano-Bicocca
- 20126 Milano
- Italy
| | - M. Forcella
- Department of Biotechnology and Biosciences
- University of Milano-Bicocca
- 20126 Milano
- Italy
| | - L. Zoia
- Department of Earth and Environmental Science
- University of Milano-Bicocca
- 20126 Milan
- Italy
| | - P. Fusi
- Department of Biotechnology and Biosciences
- University of Milano-Bicocca
- 20126 Milano
- Italy
| | - P. Di Gennaro
- Department of Biotechnology and Biosciences
- University of Milano-Bicocca
- 20126 Milano
- Italy
| | - B. La Ferla
- Department of Biotechnology and Biosciences
- University of Milano-Bicocca
- 20126 Milano
- Italy
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de Figueiredo P, Ficht TA, Rice-Ficht A, Rossetti CA, Adams LG. Pathogenesis and immunobiology of brucellosis: review of Brucella-host interactions. THE AMERICAN JOURNAL OF PATHOLOGY 2015; 185:1505-17. [PMID: 25892682 DOI: 10.1016/j.ajpath.2015.03.003] [Citation(s) in RCA: 272] [Impact Index Per Article: 30.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Revised: 02/10/2015] [Accepted: 03/02/2015] [Indexed: 01/18/2023]
Abstract
This review of Brucella-host interactions and immunobiology discusses recent discoveries as the basis for pathogenesis-informed rationales to prevent or treat brucellosis. Brucella spp., as animal pathogens, cause human brucellosis, a zoonosis that results in worldwide economic losses, human morbidity, and poverty. Although Brucella spp. infect humans as an incidental host, 500,000 new human infections occur annually, and no patient-friendly treatments or approved human vaccines are reported. Brucellae display strong tissue tropism for lymphoreticular and reproductive systems with an intracellular lifestyle that limits exposure to innate and adaptive immune responses, sequesters the organism from the effects of antibiotics, and drives clinical disease manifestations and pathology. Stealthy brucellae exploit strategies to establish infection, including i) evasion of intracellular destruction by restricting fusion of type IV secretion system-dependent Brucella-containing vacuoles with lysosomal compartments, ii) inhibition of apoptosis of infected mononuclear cells, and iii) prevention of dendritic cell maturation, antigen presentation, and activation of naive T cells, pathogenesis lessons that may be informative for other intracellular pathogens. Data sets of next-generation sequences of Brucella and host time-series global expression fused with proteomics and metabolomics data from in vitro and in vivo experiments now inform interactive cellular pathways and gene regulatory networks enabling full-scale systems biology analysis. The newly identified effector proteins of Brucella may represent targets for improved, safer brucellosis vaccines and therapeutics.
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Affiliation(s)
- Paul de Figueiredo
- Department of Veterinary Pathobiology, Texas A&M University and Texas AgriLife Research, College Station, Texas; Norman Borlaug Center, Texas A&M University, College Station, Texas; Department of Microbial Pathogenesis and Immunology, Texas A&M Health Science Center, Bryan, Texas
| | - Thomas A Ficht
- Department of Veterinary Pathobiology, Texas A&M University and Texas AgriLife Research, College Station, Texas
| | - Allison Rice-Ficht
- Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, Bryan, Texas
| | - Carlos A Rossetti
- Institute of Pathobiology, CICVyA-CNIA, National Institute of Animal Agriculture Technology (INTA), Buenos Aires, Argentina
| | - L Garry Adams
- Department of Veterinary Pathobiology, Texas A&M University and Texas AgriLife Research, College Station, Texas.
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Aruni AW, Zhang K, Dou Y, Fletcher H. Proteome analysis of coinfection of epithelial cells with Filifactor alocis and Porphyromonas gingivalis shows modulation of pathogen and host regulatory pathways. Infect Immun 2014; 82:3261-74. [PMID: 24866790 PMCID: PMC4136196 DOI: 10.1128/iai.01727-14] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2014] [Accepted: 05/15/2014] [Indexed: 12/28/2022] Open
Abstract
Changes in periodontal status are associated with shifts in the composition of the bacterial community in the periodontal pocket. The relative abundances of several newly recognized microbial species, including Filifactor alocis, as-yet-unculturable organisms, and other fastidious organisms have raised questions on their impact on disease development. We have previously reported that the virulence attributes of F. alocis are enhanced in coculture with Porphyromonas gingivalis. We have evaluated the proteome of host cells and F. alocis during a polymicrobial infection. Coinfection of epithelial cells with F. alocis and P. gingivalis strains showed approximately 20% to 30% more proteins than a monoinfection. Unlike F. alocis ATCC 35896, the D-62D strain expressed more proteins during coculture with P. gingivalis W83 than with P. gingivalis 33277. Proteins designated microbial surface component-recognizing adhesion matrix molecules (MSCRAMMs) and cell wall anchor proteins were highly upregulated during the polymicrobial infection. Ultrastructural analysis of the epithelial cells showed formation of membrane microdomains only during coinfection. The proteome profile of epithelial cells showed proteins related to cytoskeletal organization and gene expression and epigenetic modification to be in high abundance. Modulation of proteins involved in apoptotic and cell signaling pathways was noted during coinfection. The enhanced virulence potential of F. alocis may be related to the differential expression levels of several putative virulence factors and their effects on specific host cell pathways.
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Affiliation(s)
- A Wilson Aruni
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, California, USA
| | - Kangling Zhang
- University of Texas Medical branch at Galveston, Galveston, Texas, USA
| | - Yuetan Dou
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, California, USA
| | - Hansel Fletcher
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, California, USA
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Han X, Tong Y, Tian M, Sun X, Wang S, Ding C, Yu S. Characterization of the immunogenicity and pathogenicity of malate dehydrogenase in Brucella abortus. World J Microbiol Biotechnol 2014; 30:2063-70. [PMID: 24609497 DOI: 10.1007/s11274-014-1631-2] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Accepted: 03/04/2014] [Indexed: 01/24/2023]
Abstract
Brucella abortus is a gram-negative, facultative intracellular pathogen that causes brucellosis, a chronic zoonotic disease resulting in abortion in pregnant cattle and undulant fever in humans. Malate dehydrogenase (MDH), a key enzyme in the tricarboxylic acid cycle, plays important metabolic roles in aerobic energy producing pathways and in malate shuttle. In this study, the MDH-encoding gene for malate dehydrogenase mdh of B. abortus S2308 was cloned, sequenced and expressed. Western blot analysis demonstrated that MDH is an immunogenic membrane-associated protein. In addition, recombinant MDH showed sero-reactivity with 30 individual bovine B. abortus-positive sera by enzyme-linked immunosorbent assay, indicates that MDH may be used as a candidate marker for sero-diagnosis of brucellosis. Furthermore, MDH exhibits fibronectin and plasminogen-binding ability in immunoblotting assay. Inhibition assays on HeLa cells demonstrated that rabbit anti-serum against MDH significantly reduced both bacterial adherence and invasion abilities (p < 0.05), suggesting that MDH play a role in B. abortus colonization. Our results indicated that MDH is not only an immunogenic protein, but is also related to bacterial pathogenesis and may act as a new virulent factor, which will benefit for further understanding the MDH's roles in B. abortus metabolism, pathogenesis and immunity.
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Affiliation(s)
- Xiangan Han
- Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences (CAAS), 518 Ziyue Road, Shanghai, 200241, People's Republic of China
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Rossetti CA, Drake KL, Siddavatam P, Lawhon SD, Nunes JES, Gull T, Khare S, Everts RE, Lewin HA, Adams LG. Systems biology analysis of Brucella infected Peyer's patch reveals rapid invasion with modest transient perturbations of the host transcriptome. PLoS One 2013; 8:e81719. [PMID: 24349118 PMCID: PMC3857238 DOI: 10.1371/journal.pone.0081719] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2013] [Accepted: 10/21/2013] [Indexed: 01/12/2023] Open
Abstract
Brucella melitensis causes the most severe and acute symptoms of all Brucella species in human beings and infects hosts primarily through the oral route. The epithelium covering domed villi of jejunal-ileal Peyer's patches is an important site of entry for several pathogens, including Brucella. Here, we use the calf ligated ileal loop model to study temporal in vivo Brucella-infected host molecular and morphological responses. Our results document Brucella bacteremia occurring within 30 min after intraluminal inoculation of the ileum without histopathologic traces of lesions. Based on a system biology Dynamic Bayesian Network modeling approach (DBN) of microarray data, a very early transient perturbation of the host enteric transcriptome was associated with the initial host response to Brucella contact that is rapidly averted allowing invasion and dissemination. A detailed analysis revealed active expression of Syndecan 2, Integrin alpha L and Integrin beta 2 genes, which may favor initial Brucella adhesion. Also, two intestinal barrier-related pathways (Tight Junction and Trefoil Factors Initiated Mucosal Healing) were significantly repressed in the early stage of infection, suggesting subversion of mucosal epithelial barrier function to facilitate Brucella transepithelial migration. Simultaneously, the strong activation of the innate immune response pathways would suggest that the host mounts an appropriate protective immune response; however, the expression of the two key genes that encode innate immunity anti-Brucella cytokines such as TNF-α and IL12p40 were not significantly changed throughout the study. Furthermore, the defective expression of Toll-Like Receptor Signaling pathways may partially explain the lack of proinflammatory cytokine production and consequently the absence of morphologically detectable inflammation at the site of infection. Cumulatively, our results indicate that the in vivo pathogenesis of the early infectious process of Brucella is primarily accomplished by compromising the mucosal immune barrier and subverting critical immune response mechanisms.
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Affiliation(s)
- Carlos A. Rossetti
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, United States of America
| | - Kenneth L. Drake
- Seralogix, Limited Liability Corporation, Austin, Texas, United States of America
| | - Prasad Siddavatam
- Seralogix, Limited Liability Corporation, Austin, Texas, United States of America
| | - Sara D. Lawhon
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, United States of America
| | - Jairo E. S. Nunes
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, United States of America
| | - Tamara Gull
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, United States of America
| | - Sangeeta Khare
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, United States of America
| | - Robin E. Everts
- Department of Animal Sciences, University of Illinois, Urbana, Illinois, United States of America
| | - Harris A. Lewin
- Department of Animal Sciences, University of Illinois, Urbana, Illinois, United States of America
| | - Leslie Garry Adams
- Department of Veterinary Pathobiology, College of Veterinary Medicine and Biomedical Sciences, Texas A&M University, College Station, Texas, United States of America
- * E-mail:
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Ruiz-Ranwez V, Posadas DM, Estein SM, Abdian PL, Martin FA, Zorreguieta A. The BtaF trimeric autotransporter of Brucella suis is involved in attachment to various surfaces, resistance to serum and virulence. PLoS One 2013; 8:e79770. [PMID: 24236157 PMCID: PMC3827427 DOI: 10.1371/journal.pone.0079770] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 10/02/2013] [Indexed: 02/02/2023] Open
Abstract
The adhesion of bacterial pathogens to host cells is an event that determines infection, and ultimately invasion and intracellular multiplication. Several evidences have recently shown that this rule is also truth for the intracellular pathogen Brucella. Brucella suis displays the unipolar BmaC and BtaE adhesins, which belong to the monomeric and trimeric autotransporter (TA) families, respectively. It was previously shown that these adhesins are involved in bacterial adhesion to host cells and components of the extracellular matrix (ECM). In this work we describe the role of a new member of the TA family of B. suis (named BtaF) in the adhesive properties of the bacterial surface. BtaF conferred the bacteria that carried it a promiscuous adhesiveness to various ECM components and the ability to attach to an abiotic surface. Furthermore, BtaF was found to participate in bacterial adhesion to epithelial cells and was required for full virulence in mice. Similar to BmaC and BtaE, the BtaF adhesin was expressed in a small subpopulation of bacteria, and in all cases, it was detected at the new pole generated after cell division. Interestingly, BtaF was also implicated in the resistance of B. suis to porcine serum. Our findings emphasize the impact of TAs in the Brucella lifecycle.
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Van der Henst C, de Barsy M, Zorreguieta A, Letesson JJ, De Bolle X. The Brucella pathogens are polarized bacteria. Microbes Infect 2013; 15:998-1004. [PMID: 24141086 DOI: 10.1016/j.micinf.2013.10.008] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2013] [Revised: 10/01/2013] [Accepted: 10/03/2013] [Indexed: 11/30/2022]
Abstract
Brucella pathogens are responsible for brucellosis, a worldwide zoonosis. They are facultative intracellular pathogens characterized by their asymmetric division and their unipolar growth. This growth modality generates poles with specialized functions (through polar recruitment of polar adhesins or of cell cycle regulators) and progeny cells with potentially different fates.
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Affiliation(s)
- Charles Van der Henst
- Global Health Institute, School of Life Sciences, Ecole Polytechnique Fédérale de Lausanne (EPFL), Station 19, 1015 Lausanne, Switzerland
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26
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Martín R, Martín C, Escobedo S, Suárez JE, Quirós LM. Surface glycosaminoglycans mediate adherence between HeLa cells and Lactobacillus salivarius Lv72. BMC Microbiol 2013; 13:210. [PMID: 24044741 PMCID: PMC3848620 DOI: 10.1186/1471-2180-13-210] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2013] [Accepted: 09/11/2013] [Indexed: 02/05/2023] Open
Abstract
Background The adhesion of lactobacilli to the vaginal surface is of paramount importance to develop their probiotic functions. For this reason, the role of HeLa cell surface proteoglycans in the attachment of Lactobacillus salivarius Lv72, a mutualistic strain of vaginal origin, was investigated. Results Incubation of cultures with a variety of glycosaminoglycans (chondroitin sulfate A and C, heparin and heparan sulfate) resulted in marked binding interference. However, no single glycosaminoglycan was able to completely abolish cell binding, the sum of all having an additive effect that suggests cooperation between them and recognition of specific adhesins on the bacterial surface. In contrast, chondroitin sulfate B enhanced cell to cell attachment, showing the relevance of the stereochemistry of the uronic acid and the sulfation pattern on binding. Elimination of the HeLa surface glycosaminoglycans with lyases also resulted in severe adherence impairment. Advantage was taken of the Lactobacillus-glycosaminoglycans interaction to identify an adhesin from the bacterial surface. This protein, identify as a soluble binding protein of an ABC transporter system (OppA) by MALDI-TOF/(MS), was overproduced in Escherichia coli, purified and shown to interfere with L. salivarius Lv72 adhesion to HeLa cells. Conclusions These data suggest that glycosaminoglycans play a fundamental role in attachment of mutualistic bacteria to the epithelium that lines the cavities where the normal microbiota thrives, OppA being a bacterial adhesin involved in the process.
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Affiliation(s)
- Rebeca Martín
- Área de Microbiología, Universidad de Oviedo, Julián Clavería 6 33006 Oviedo, Spain.
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27
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Aruni AW, Roy F, Sandberg L, Fletcher HM. Proteome variation among Filifactor alocis strains. Proteomics 2013; 12:3343-64. [PMID: 23008013 DOI: 10.1002/pmic.201200211] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2012] [Revised: 08/23/2012] [Accepted: 09/03/2012] [Indexed: 01/12/2023]
Abstract
Filifactor alocis, a Gram-positive anaerobic rod, is now considered one of the marker organisms associated with periodontal disease. Although there was heterogeneity in its virulence potential, this bacterium was shown to have virulence properties that may enhance its ability to survive and persist in the periodontal pocket. To gain further insight into a possible mechanism(s) of pathogenesis, the proteome of F. alocis strains was evaluated. Proteins including several proteases, neutrophil-activating protein A and calcium-binding acid repeat protein, were identified in F. alocis. During the invasion of HeLa cells, there was increased expression of several of the genes encoding these proteins in the potentially more virulent F. alocis D-62D compared to F. alocis ATCC 35896, the type strain. A comparative protein in silico analysis of the proteome revealed more cell wall anchoring proteins in the F. alocis D-62D compared to F. alocis ATCC 35896. Their expression was enhanced by coinfection with Porphyromonas gingivalis. Taken together, the variation in the pathogenic potential of the F. alocis strains may be related to the differential expression of several putative virulence factors.
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Affiliation(s)
- A Wilson Aruni
- Division of Microbiology and Molecular Genetics, School of Medicine, Loma Linda University, Loma Linda, CA 92350, USA
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28
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BtaE, an adhesin that belongs to the trimeric autotransporter family, is required for full virulence and defines a specific adhesive pole of Brucella suis. Infect Immun 2013; 81:996-1007. [PMID: 23319562 DOI: 10.1128/iai.01241-12] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
Brucella is responsible for brucellosis, one of the most common zoonoses worldwide that causes important economic losses in several countries. Increasing evidence indicates that adhesion of Brucella spp. to host cells is an important step to establish infection. We have previously shown that the BmaC unipolar monomeric autotransporter mediates the binding of Brucella suis to host cells through cell-associated fibronectin. Our genome analysis shows that the B. suis genome encodes several additional potential adhesins. In this work, we characterized a predicted trimeric autotransporter that we named BtaE. By expressing btaE in a nonadherent Escherichia coli strain and by phenotypic characterization of a B. suis ΔbtaE mutant, we showed that BtaE is involved in the binding of B. suis to hyaluronic acid. The B. suis ΔbtaE mutant exhibited a reduction in the adhesion to HeLa and A549 epithelial cells compared with the wild-type strain, and it was outcompeted by the wild-type strain in the binding to HeLa cells. The knockout btaE mutant showed an attenuated phenotype in the mouse model, indicating that BtaE is required for full virulence. BtaE was immunodetected on the bacterial surface at one cell pole. Using old and new pole markers, we observed that both the BmaC and BtaE adhesins are consistently associated with the new cell pole, suggesting that, in Brucella, the new pole is functionally differentiated for adhesion. This is consistent with the inherent polarization of this bacterium, and its role in the invasion process.
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Attenuation of Streptococcus suis virulence by the alteration of bacterial surface architecture. Sci Rep 2012; 2:710. [PMID: 23050094 PMCID: PMC3464449 DOI: 10.1038/srep00710] [Citation(s) in RCA: 51] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2012] [Accepted: 09/14/2012] [Indexed: 01/09/2023] Open
Abstract
NeuB, a sialic acid synthase catalyzes the last committed step of the de novo biosynthetic pathway of sialic acid, a major element of bacterial surface structure. Here we report a functional NeuB homologue of Streptococcus suis, a zoonotic agent, and systematically address its molecular and immunological role in bacterial virulence. Disruption of neuB led to thinner capsules and more susceptibility to pH, and cps2B inactivation resulted in complete absence of capsular polysaccharides. These two mutants both exhibited increased adhesion and invasion to Hep-2 cells and improved sensibility to phagocytosis. Not only do they retain the capability of inducing the release of host pro-inflammatory cytokines, but also result in the faster secretion of IL-8. Easier cleaning up of the mutant strains in whole blood is consistent with virulence attenuation seen with experimental infections of both mice and SPF-piglets. Therefore we concluded that altered architecture of S. suis surface attenuates its virulence.
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Rossetti CA, Drake KL, Adams LG. Transcriptome analysis of HeLa cells response to Brucella melitensis infection: a molecular approach to understand the role of the mucosal epithelium in the onset of the Brucella pathogenesis. Microbes Infect 2012; 14:756-67. [PMID: 22484383 PMCID: PMC3389182 DOI: 10.1016/j.micinf.2012.03.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Revised: 03/03/2012] [Accepted: 03/15/2012] [Indexed: 12/31/2022]
Abstract
Brucella spp. infect hosts primarily by adhering and penetrating mucosal surfaces, however the initial molecular phenomena of this host:pathogen interaction remain poorly understood. We hypothesized that characterizing the epithelial-like human HeLa cell line molecular response to wild type Brucella melitensis infection would help to understand the role of the mucosal epithelium at the onset of the Brucella pathogenesis. RNA samples from B. melitensis-infected HeLa cells were taken at 4 and 12 h of infection and hybridized in a cDNA microarray. The analysis using a dynamic Bayesian network modeling approach (DBN) identified several pathways, biological processes, cellular components and molecular functions altered due to infection at 4 h p.i., but almost none at 12 h p.i. The in silico modeling results were experimentally tested by knocking down the expression of MAPK1 by siRNA technology. MAPK1-siRNA transfected cell cultures decreased the internalization and impaired the intracellular replication of the pathogen in HeLa cells after 4 h p.i. DBN analysis provides important insights into the role of the epithelial cells response to Brucella infection and guide research to novel mechanisms identification.
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Affiliation(s)
- Carlos A. Rossetti
- Department of Veterinary Pathobiology, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, TX 77843-4467, USA
| | | | - L. Garry Adams
- Department of Veterinary Pathobiology, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, TX 77843-4467, USA
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31
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Singh B, Fleury C, Jalalvand F, Riesbeck K. Human pathogens utilize host extracellular matrix proteins laminin and collagen for adhesion and invasion of the host. FEMS Microbiol Rev 2012; 36:1122-80. [PMID: 22537156 DOI: 10.1111/j.1574-6976.2012.00340.x] [Citation(s) in RCA: 206] [Impact Index Per Article: 17.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2011] [Revised: 02/08/2012] [Accepted: 03/29/2012] [Indexed: 01/11/2023] Open
Abstract
Laminin (Ln) and collagen are multifunctional glycoproteins that play an important role in cellular morphogenesis, cell signalling, tissue repair and cell migration. These proteins are ubiquitously present in tissues as a part of the basement membrane (BM), constitute a protective layer around blood capillaries and are included in the extracellular matrix (ECM). As a component of BMs, both Lns and collagen(s), thus function as major mechanical containment molecules that protect tissues from pathogens. Invasive pathogens breach the basal lamina and degrade ECM proteins of interstitial spaces and connective tissues using various ECM-degrading proteases or surface-bound plasminogen and matrix metalloproteinases recruited from the host. Most pathogens associated with the respiratory, gastrointestinal, or urogenital tracts, as well as with the central nervous system or the skin, have the capacity to bind and degrade Lns and collagen(s) in order to adhere to and invade host tissues. In this review, we focus on the adaptability of various pathogens to utilize these ECM proteins as enhancers for adhesion to host tissues or as a targets for degradation in order to breach the cellular barriers. The major pathogens discussed are Streptococcus, Staphylococcus, Pseudomonas, Salmonella, Yersinia, Treponema, Mycobacterium, Clostridium, Listeria, Porphyromonas and Haemophilus; Candida, Aspergillus, Pneumocystis, Cryptococcus and Coccidioides; Acanthamoeba, Trypanosoma and Trichomonas; retrovirus and papilloma virus.
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Affiliation(s)
- Birendra Singh
- Medical Microbiology, Department of Laboratory Medicine Malmö, Skåne University Hospital, Lund University, Malmö, Sweden
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32
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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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Posadas DM, Ruiz-Ranwez V, Bonomi HR, Martín FA, Zorreguieta A. BmaC, a novel autotransporter of Brucella suis, is involved in bacterial adhesion to host cells. Cell Microbiol 2012; 14:965-82. [PMID: 22321605 DOI: 10.1111/j.1462-5822.2012.01771.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Brucella is an intracellular pathogen responsible of a zoonotic disease called brucellosis. Brucella survives and proliferates within several types of phagocytic and non-phagocytic cells. Like in other pathogens, adhesion of brucellae to host surfaces was proposed to be an important step in the infection process. Indeed, Brucella has the capacity to bind to culture human cells and key components of the extracellular matrix, such as fibronectin. However, little is known about the molecular bases of Brucella adherence. In an attempt to identify bacterial genes encoding adhesins, a phage display library of Brucella suis was panned against fibronectin. Three fibronectin-binding proteins of B. suis were identified using this approach. One of the candidates, designated BmaC was a very large protein of 340 kDa that is predicted to belong to the type I (monomeric) autotransporter family. Microscopy studies showed that BmaC is located at one pole on the bacterial surface. The phage displaying the fibronectin-binding peptide of BmaC inhibited the attachment of brucellae to both, HeLa cells and immobilized fibronectin in vitro. In addition, a bmaC deletion mutant was impaired in the ability of B. suis to attach to immobilized fibronectin and to the surface of HeLa and A549 cells and was out-competed by the wild-type strain in co-infection experiments. Finally, anti-fibronectin or anti-BmaC antibodies significantly inhibited the binding of wild-type bacteria to HeLa cells. Our results highlight the role of a novel monomeric autotransporter protein in the adhesion of B. suis to the extracellular matrix and non-phagocytic cells via fibronectin binding.
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Affiliation(s)
- Diana M Posadas
- Fundación Instituto Leloir, IIBBA CONICET and FCEyN, Universidad de Buenos Aires, Patricias Argentinas 435, (C1405BWE) Buenos Aires, Argentina
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34
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Cao M, Feng Y, Wang C, Zheng F, Li M, Liao H, Mao Y, Pan X, Wang J, Hu D, Hu F, Tang J. Functional definition of LuxS, an autoinducer-2 (AI-2) synthase and its role in full virulence of Streptococcus suis serotype 2. J Microbiol 2011; 49:1000-11. [PMID: 22203565 DOI: 10.1007/s12275-011-1523-1] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2011] [Accepted: 12/13/2011] [Indexed: 12/22/2022]
Abstract
Quorum sensing is a widespread chemical communication in response to fluctuation of bacterial population density, and has been implicated into bacterial biofilm formation and regulation of expression of virulence factors. The luxS gene product, S-ribosylhomocysteinase, catalizes the last committed step in biosynthetic pathway of autoinducer 2 (AI-2), a signaling molecule for inter-species quorum sensing. We found a luxS homologue in 05ZYH33, an epidemic strain of Streptococcus suis serotype 2 (SS2) in China. A luxS null mutant (ΔluxS) of 05ZYH33 strain was obtained using an approach of homologous recombination. LuxS was determined to be required for AI-2 production in 05ZYH33 strain of S. suis 2. Inactivation of luxS gene led to a wide range of phenotypic changes including thinner capsular walls, increased tolerance to H(2)O(2), reduced adherence capacity to epithelial cells, etc. In particular, loss of LuxS impaired dramatically its full virulence of SS2 in experimental model of piglets, and functional complementation restored it nearly to the level of parent strain. Genome-wide transcriptome analyses suggested that some known virulence factors such as CPS are down-regulated in the ΔluxS mutant, which might in part explain virulence attenuation by luxS deletion. Similarly, 29 of 71 genes with different expression level were proposed to be targets candidate regulated by LuxS/AI-2-dependent quorum sensing.
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Affiliation(s)
- Min Cao
- Department of Microbiology, Third Military Medical University, Chongqing, P. R. China
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VimA-dependent modulation of acetyl coenzyme A levels and lipid A biosynthesis can alter virulence in Porphyromonas gingivalis. Infect Immun 2011; 80:550-64. [PMID: 22144476 DOI: 10.1128/iai.06062-11] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
The Porphyromonas gingivalis VimA protein has multifunctional properties that can modulate several of its major virulence factors. To further characterize VimA, P. gingivalis FLL406 carrying an additional vimA gene and a vimA-defective mutant in a different P. gingivalis genetic background were evaluated. The vimA-defective mutant (FLL451) in the P. gingivalis ATCC 33277 genetic background showed a phenotype similar to that of the vimA-defective mutant (FLL92) in the P. gingivalis W83 genetic background. In contrast to the wild type, gingipain activity was increased in P. gingivalis FLL406, a vimA chimeric strain. P. gingivalis FLL451 had a five times higher biofilm-forming capacity than the parent strain. HeLa cells incubated with P. gingivalis FLL92 showed a decrease in invasion, in contrast to P. gingivalis FLL451 and FLL406, which showed increases of 30 and 40%, respectively. VimA mediated coenzyme A (CoA) transfer to isoleucine and reduced branched-chain amino acid metabolism. The lipid A content and associated proteins were altered in the vimA-defective mutants. The VimA chimera interacted with several proteins which were found to have an LXXTG motif, similar to the sorting motif of gram-positive organisms. All the proteins had an N-terminal signal sequence with a putative sorting signal of L(P/T/S)X(T/N/D)G and two unique signatures of EXGXTX and HISXXGXG, in addition to a polar tail. Taken together, these observations further confirm the multifunctional role of VimA in modulating virulence possibly through its involvement in acetyl-CoA transfer and lipid A synthesis and possibly by protein sorting.
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Thomas RJ. Receptor mimicry as novel therapeutic treatment for biothreat agents. Bioeng Bugs 2011; 1:17-30. [PMID: 21327124 DOI: 10.4161/bbug.1.1.10049] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2009] [Revised: 09/10/2009] [Accepted: 09/11/2009] [Indexed: 12/20/2022] Open
Abstract
The specter of intentional release of pathogenic microbes and their toxins is a real threat. This article reviews the literature on adhesins of biothreat agents, their interactions with oligosaccharides and the potential for anti-adhesion compounds as an alternative to conventional therapeutics. The minimal binding structure of ricin has been well characterised and offers the best candidate for successful anti-adhesion therapy based on the Galβ1-4GlcNAc structure. The botulinum toxin serotypes A-F bind to a low number of gangliosides (GT1b, GQ1b, GD1a and GD1b) hence it should be possible to determine the minimal structure for binding. The minimal disaccharide sequence of GalNAcβ1-4Gal found in the gangliosides asialo-GM1 and asialo-GM2 is required for adhesion for many respiratory pathogens. Although a number of adhesins have been identified in bacterial biothreat agents such as Yersinia pestis, Bacillus anthracis, Francisella tularensis, Brucella species and Burkholderia pseudomallei, specific information regarding their in vivo expression during pneumonic infection is lacking. Limited oligosaccharide inhibition studies indicate the potential of GalNAcβ1-4Gal, GalNAcβ-3Gal and the hydrophobic compound, para-nitrophenol as starting points for the rational design of generic anti-adhesion compounds. A cocktail of multivalent oligosaccharides based on the minimal binding structures of identified adhesins would offer the best candidates for anti-adhesion therapy.
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Czibener C, Ugalde JE. Identification of a unique gene cluster of Brucella spp. that mediates adhesion to host cells. Microbes Infect 2011; 14:79-85. [PMID: 21911075 DOI: 10.1016/j.micinf.2011.08.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2011] [Revised: 07/19/2011] [Accepted: 08/20/2011] [Indexed: 12/29/2022]
Abstract
Brucella, the causative agent of brucellosis, a major zoonotic disease affecting a broad range of mammals, is a gram-negative bacterium whose virulence is dependent on the capacity to attach and invade different cells of the host. The bacterium is able to infect through a diverse repertoire of epitheliums: skin, airways or gastric. Although much has been studied on the mechanisms Brucella uses to establish an intracellular replication niche, almost none is known on how the bacterium adheres and invades host cells. We report here the identification of a pathogenicity island that harbors a gene homologous to proteins with bacterial immunoglobulin-like domains present in other pathogens that play a role in attachment and invasion. Deletion of the entire island results in a mutant with a reduced attachment capacity measured by intracellular replication and adhesion assays. Intraperitoneal and oral experimental infection of mice strongly suggests that this island plays a role during the oral infection probably mediating attachment and trespassing of the gastric epithelium to establish a systemic infection.
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Affiliation(s)
- Cecilia Czibener
- Instituto de Investigaciones Biotecnológicas Dr. Rodolfo A. Ugalde, IIB-INTECH, CONICET, Universidad Nacional de San Martín, San Martín, Buenos Aires, Argentina
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Filifactor alocis has virulence attributes that can enhance its persistence under oxidative stress conditions and mediate invasion of epithelial cells by porphyromonas gingivalis. Infect Immun 2011; 79:3872-86. [PMID: 21825062 DOI: 10.1128/iai.05631-11] [Citation(s) in RCA: 88] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Filifactor alocis, a Gram-positive anaerobic rod, is one of the most abundant bacteria identified in the periodontal pockets of periodontitis patients. There is a gap in our understanding of its pathogenicity and ability to interact with other periodontal pathogens. To evaluate the virulence potential of F. alocis and its ability to interact with Porphyromonas gingivalis W83, several clinical isolates of F. alocis were characterized. F. alocis showed nongingipain protease and sialidase activities. In silico analysis revealed the molecular relatedness of several virulence factors from F. alocis and P. gingivalis. In contrast to P. gingivalis, F. alocis was relatively resistant to oxidative stress and its growth was stimulated under those conditions. Biofilm formation was significantly increased in coculture. There was an increase in adherence and invasion of epithelial cells in coculture compared with P. gingivalis or F. alocis monocultures. In those epithelial cells, endocytic vesicle-mediated internalization was observed only during coculture. The F. alocis clinical isolate had an increased invasive capacity in coculture with P. gingivalis compared to the ATCC 35896 strain. In addition, there was variation in the proteomes of the clinical isolates compared to the ATCC 35896 strain. Hypothetical proteins and those known to be important virulence factors in other bacteria were identified. These results indicate that F. alocis has virulence properties that may enhance its ability to survive and persist in the periodontal pocket and may play an important role in infection-induced periodontal disease.
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Sialidase and sialoglycoproteases can modulate virulence in Porphyromonas gingivalis. Infect Immun 2011; 79:2779-91. [PMID: 21502589 DOI: 10.1128/iai.00106-11] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
The Porphyromonas gingivalis recombinant VimA can interact with the gingipains and several other proteins, including a sialidase. Sialylation can be involved in protein maturation; however, its role in virulence regulation in P. gingivalis is unknown. The three sialidase-related proteins in P. gingivalis showed the characteristic sialidase Asp signature motif (SXDXGXTW) and other unique domains. To evaluate the roles of the associated genes, randomly chosen P. gingivalis isogenic mutants created by allelic exchange and designated FLL401 (PG0778::ermF), FLL402 (PG1724::ermF), and FLL403 (PG0352::ermF-ermAM) were characterized. Similar to the wild-type strain, FLL402 and FLL403 displayed a black-pigmented phenotype in contrast to FLL401, which was not black pigmented. Sialidase activity in P. gingivalis FLL401 was reduced by approximately 70% in comparison to those in FLL402 and FLL403, which were reduced by approximately 42% and 5%, respectively. Although there were no changes in the expression of the gingipain genes, their activities were reduced by 60 to 90% in all the isogenic mutants compared to that for the wild type. Immunoreactive bands representing the catalytic domains for RgpA, RgpB, and Kgp were present in FLL402 and FLL403 but were missing in FLL401. While adhesion was decreased, the capacity for invasion of epithelial cells by the isogenic mutants was increased by 11 to 16% over that of the wild-type strain. Isogenic mutants defective in PG0778 and PG0352 were more sensitive to hydrogen peroxide than the wild type. Taken together, these results suggest that the P. gingivalis sialidase activity may be involved in regulating gingipain activity and other virulence factors and may be important in the pathogenesis of this organism.
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Godefroid M, Svensson MV, Cambier P, Uzureau S, Mirabella A, De Bolle X, Van Cutsem P, Widmalm G, Letesson JJ. Brucella melitensis 16M produces a mannan and other extracellular matrix components typical of a biofilm. ACTA ACUST UNITED AC 2010; 59:364-77. [PMID: 20497223 DOI: 10.1111/j.1574-695x.2010.00689.x] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Mutations in the Brucella melitensis quorum-sensing (QS) system are involved in the formation of clumps containing an exopolysaccharide. Here, we show that the overexpression of a gene called aiiD in B. melitensis gives rise to a similar clumping phenotype. The AiiD enzyme degrades AHL molecules and leads therefore to a QS-deficient strain. We demonstrated the presence of exopolysaccharide and DNA, two classical components of extracellular matrices, in clumps produced by this strain. We also observed that the production of outer membrane vesicles is strongly increased in the aiiD-overexpressing strain. Moreover, this strain allowed us to purify the exopolysaccharide and to obtain its composition and the first structural information on the complex exopolysaccharide produced by B. melitensis 16M, which was found to have a molecular weight of about 16 kDa and to be composed of glucosamine, glucose and mostly mannose. In addition, we found the presence of 2- and/or 6-substituted mannosyl residues, which provide the first insights into the linkages involved in this polymer. We used a classical biofilm attachment assay and an HeLa cell infection model to demonstrate that the clumping strain is more adherent to polystyrene plates and to HeLa cell surfaces than the wild-type one. Taken together, these data reinforce the evidence that B. melitensis could form biofilms in its lifecycle.
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Affiliation(s)
- Marie Godefroid
- Unité de Recherche en Biologie Moléculaire, Facultés Universitaires Notre-Dame de la Paix, Namur, Belgium
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Samadder P, Xicohtencatl-Cortes J, Saldana Z, Jordan D, Tarr PI, Kaper JB, Giron JA. The Escherichia coli ycbQRST operon encodes fimbriae with laminin-binding and epithelial cell adherence properties in Shiga-toxigenic E. coli O157:H7. Environ Microbiol 2009; 11:1815-26. [PMID: 19508558 PMCID: PMC2888687 DOI: 10.1111/j.1462-2920.2009.01906.x] [Citation(s) in RCA: 39] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The human pathogen Shiga-toxigenic Escherichia coli (STEC) O157:H7 contains a ycbQRST fimbrial-like operon, which shares significant homology to the family of F17 fimbrial biogenesis genes f17ADCG found in enterotoxigenic E. coli. We report that growth of STEC O157:H7 strain EDL933 in minimal Minca medium at 37°C and during adherence to epithelial cells led to the production of fine peritrichous fimbriae, which were found to be composed of a major subunit of 18 kDa whose N-terminal amino acid sequence matched the predicted protein product of the ycbQ gene; and showed significant homology to the F17a-A fimbrin. Similar to the F17 fimbriae, the purified STEC fimbriae and the recombinant YcbQ protein fused to a His peptide tag bound laminin, but not fibronectin or collagen. Thus, we propose the name E. coli YcbQ laminin-binding fimbriae (ELF) to designate the fimbriae encoded by the ycbQRST operon. The role of ELF as an adherence factor of STEC to cultured epithelial cells was investigated. We provide compelling evidence demonstrating that ELF contributes to adherence of STEC to human intestinal epithelial cells and to cow and pig gut tissue in vitro. Deletion in the fimbrin subunit gene elfA (or ycbQ) in STEC strain EDL933 led to an isogenic strain, which showed significant reduction (60%) in adherence to HEp-2 cells in comparison with the parental strain. In addition, antibodies against the purified ELF also partially blocked adherence of two STEC O157:H7 strains. These observations suggest that ELF functions as an accessory adherence factor that, along with other known redundant adhesins, contributes to the overall adhesive properties of STEC O157:H7 providing these organisms with ecological advantages to survive in different hosts and in the environment.
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Affiliation(s)
- Partha Samadder
- Department of Immunobiology, University of Arizona, Tucson, AZ, 85724, USA
| | | | - Zeus Saldana
- Department of Immunobiology, University of Arizona, Tucson, AZ, 85724, USA
| | - Dianna Jordan
- Department of Veterinary Diagnostic and Production Animal Medicine, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA
| | - Phillip I. Tarr
- Department of Pediatrics, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - James B. Kaper
- Department of Microbiology and Immunology, University of Maryland School of Medicine, 685 West Baltimore St., Baltimore, MD 21201, USA
| | - Jorge A. Giron
- Department of Immunobiology, University of Arizona, Tucson, AZ, 85724, USA
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Smooth Brucella strains invade and replicate in human lung epithelial cells without inducing cell death. Microbes Infect 2009; 11:476-83. [PMID: 19397873 DOI: 10.1016/j.micinf.2009.01.010] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2008] [Revised: 01/22/2009] [Accepted: 01/27/2009] [Indexed: 11/22/2022]
Abstract
Inhalation is a common route for Brucella infection. We investigated whether Brucella species can invade and replicate within alveolar(A549) and bronchial (Calu-6 and 16HBE14o-) human epithelial cells. The number of adherent and intracellular bacteria was higher for rough strains (Brucella canis and Brucella abortus RB51) than for smooth strains (B. abortus 2308 and Brucella suis 1330). Only smooth strains exhibited efficient intracellular replication (1.5-3.5 log increase at 24 h p.i.). A B. abortus mutant with defective expression of the type IV secretion system did not replicate. B. abortus internalization was inhibited by specific inhibitors of microfilaments, microtubules and PI3-kinase activity. As assessed with fluorescent probes, B. abortus infection did not affect the viability of A549 and 16HBE14o- cells, but increased the percentage of injured cells (both strains) and dead cells (RB51) in Calu-6 cultures. LDH levels were increased in supernatants of Calu-6 and 16HBE14o- cells infected with B. abortus RB51, and to a lower extent in Calu-6 infected with B. abortus 2308. No apoptosis was detected by TUNEL upon infection with smooth or rough B. abortus. This study shows that smooth brucellae can infect and replicate in human respiratory epithelial cells inducing minimal or null cytotoxicity.
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Rossetti CA, Galindo CL, Lawhon SD, Garner HR, Adams LG. Brucella melitensis global gene expression study provides novel information on growth phase-specific gene regulation with potential insights for understanding Brucella:host initial interactions. BMC Microbiol 2009; 9:81. [PMID: 19419566 PMCID: PMC2684542 DOI: 10.1186/1471-2180-9-81] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2008] [Accepted: 05/06/2009] [Indexed: 01/18/2023] Open
Abstract
BACKGROUND Brucella spp. are the etiological agents of brucellosis, a zoonotic infectious disease that causes abortion in animals and chronic debilitating illness in humans. Natural Brucella infections occur primarily through an incompletely defined mechanism of adhesion to and penetration of mucosal epithelium. In this study, we characterized changes in genome-wide transcript abundance of the most and the least invasive growth phases of B. melitensis cultures to HeLa cells, as a preliminary approach for identifying candidate pathogen genes involved in invasion of epithelial cells. RESULTS B. melitensis at the late logarithmic phase of growth are more invasive to HeLa cells than mid-logarithmic or stationary growth phases. Microarray analysis of B. melitensis gene expression identified 414 up- and 40 down-regulated genes in late-log growth phase (the most invasive culture) compared to the stationary growth phase (the least invasive culture). As expected, the majority of up-regulated genes in late-log phase cultures were those associated with growth, including DNA replication, transcription, translation, intermediate metabolism, energy production and conversion, membrane transport, and biogenesis of the cell envelope and outer membrane; while the down-regulated genes were distributed among several functional categories. CONCLUSION This Brucella global expression profile study provides novel information on growth phase-specific gene expression. Further characterization of some genes found differentially expressed in the most invasive culture will likely bring new insights into the initial molecular interactions between Brucella and its host.
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Affiliation(s)
- Carlos A Rossetti
- Department of Veterinary Pathobiology, College of Veterinary Medicine & Biomedical Sciences, Texas A&M University, College Station, TX 77483-4467, USA.
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The type 4 pili of enterohemorrhagic Escherichia coli O157:H7 are multipurpose structures with pathogenic attributes. J Bacteriol 2008; 191:411-21. [PMID: 18952791 DOI: 10.1128/jb.01306-08] [Citation(s) in RCA: 66] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Enterohemorrhagic Escherichia coli (EHEC) O157:H7 produces long bundles of polar type 4 pili (T4P) called HCP (for hemorrhagic coli pili) that form physical bridges between bacteria associating with human and animal epithelial cells. Here, we sought to further investigate whether HCP possessed other pathogenicity attributes associated with T4P production. Comparative studies performed with wild-type EHEC EDL933 and an isogenic hcpA mutant revealed that HCP play different roles in the biology of this organism. We found that in addition to promoting bacterial attachment to host cells, HCP mediate (i) invasion of epithelial cells, (ii) hemagglutination of rabbit erythrocytes, (iii) interbacterial connections conducive to biofilm formation, (iv) specific binding to host extracellular matrix proteins laminin and fibronectin but not collagen, and (v) twitching motility. Nonadherent laboratory E. coli strain HB101 complemented with hcpABC genes on plasmid pJX22, which specifies for HCP overproduction in EDL933, became hyperadherent and invasive and produced a thick biofilm, suggesting that the presence of HCP confers HB101(pJX22) new attributes otherwise not exhibited by HB101. Analogous to other bacteria in which T4P are involved in the pathogenesis of several infectious diseases, our data strongly suggest that HCP display multiple functions that may contribute to EHEC colonization of different hosts and to virulence, survival, and transmission of this food-borne pathogen.
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Pei J, Turse JE, Ficht TA. Evidence of Brucella abortus OPS dictating uptake and restricting NF-kappaB activation in murine macrophages. Microbes Infect 2008; 10:582-90. [PMID: 18457975 DOI: 10.1016/j.micinf.2008.01.005] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2007] [Revised: 12/08/2007] [Accepted: 01/11/2008] [Indexed: 11/16/2022]
Abstract
Smooth Brucella abortus S2308 is virulent while rough derivatives are attenuated. Intracellular killing is often blamed for these differences. In the studies described, uptake kinetics and interaction of S2308 and S2308 manBA::Tn5 (CA180) rough mutants with macrophages were investigated. The results revealed that smooth B. abortus was rapidly internalized, achieving a maximum level in less than 5 min without additional uptake over the next 30 min. In contrast, continued uptake of the rough mutant was observed and only achieves a maximum level after 30 min. The results were confirmed by the differences in F-actin polymerization, lipid raft staining, early endosome colocalization and electron microscopic observations after smooth and rough Brucella infection. We also demonstrated for the first time that uptake of S2308, but not rough mutant CA180 was PI3-kinase and toll-like receptor 4 (TLR4) dependent. Differences in uptake were associated with differences in macrophage activation with regard to NF-kappaB translocation and cytokine production. These results provide evidence that the presence of B. abortus OPS dictates the interactions between Brucella and specific cell surface receptors minimizing macrophage activation and enhancing Brucella survival and/or persistence.
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Affiliation(s)
- Jianwu Pei
- Department of Veterinary Pathobiology, Texas A&M University and Texas Agricultural Experiment Station, College Station, TX 77843-4467, USA
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Hernández-Castro R, Verdugo-Rodríguez A, Puente JL, Suárez-Güemes F. The BMEI0216 gene of Brucella melitensis is required for internalization in HeLa cells. Microb Pathog 2007; 44:28-33. [PMID: 17881185 DOI: 10.1016/j.micpath.2007.08.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2007] [Accepted: 08/01/2007] [Indexed: 01/18/2023]
Abstract
Brucella is an intracellular facultative bacterium able to survive and multiply in professional and non-professional phagocytes. However, its adhesion and invasion mechanisms have not been elucidated yet. In this work, we assess the interruption of a BMEI0216 gene of Brucella melitensis, by using HeLa epithelial cells and murine macrophages for invasion and replication assays. The mutation did not affect survival or multiplication within macrophages. Likewise, invasion assays with HeLa cells revealed no differences at 30 and 45 min, whereas, at 1 and 2h, the infection ability of the mutant was drastically reduced. These results suggest that the BMEI0216 gene is required for B. melitensis internalization.
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Affiliation(s)
- Rigoberto Hernández-Castro
- Departamento de Microbiología e Inmunología, Facultad de Medicina Veterinaria y Zootecnia, Universidad Nacional Autónoma de México, Coyoacán 04510, Mexico
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Uzureau S, Godefroid M, Deschamps C, Lemaire J, De Bolle X, Letesson JJ. Mutations of the quorum sensing-dependent regulator VjbR lead to drastic surface modifications in Brucella melitensis. J Bacteriol 2007; 189:6035-47. [PMID: 17557825 PMCID: PMC1952030 DOI: 10.1128/jb.00265-07] [Citation(s) in RCA: 68] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
Successful establishment of infection by bacterial pathogens requires fine-tuning of virulence-related genes. Quorum sensing (QS) is a global regulation process based on the synthesis of, detection of, and response to small diffusible molecules, called N-acyl-homoserine lactones (AHL), in gram-negative bacteria. In numerous species, QS has been shown to regulate genes involved in the establishment of pathogenic interactions with the host. Brucella melitensis produces N-dodecanoyl homoserine lactones (C(12)-HSL), which down regulate the expression of flagellar genes and of the virB operon (encoding a type IV secretion system), both of which encode surface virulence factors. A QS-related regulator, called VjbR, was identified as a transcriptional activator of these genes. We hypothesized that VjbR mediates the C(12)-HSL effects described above. vjbR alleles mutated in the region coding for the AHL binding domain were constructed to test this hypothesis. These alleles expressed in trans in a DeltavjbR background behave as constitutive regulators both in vitro and in a cellular model of infection. Interestingly, the resulting B. melitensis strains, unable to respond to AHLs, aggregate spontaneously in liquid culture. Preliminary characterization of these strains showed altered expression of some outer membrane proteins and overproduction of a matrix-forming exopolysaccharide, suggesting for the first time that B. melitensis could form biofilms. Together, these results indicate that QS through VjbR is a major regulatory system of important cell surface structures of Brucella and as such plays a key role in host-pathogen interactions.
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Affiliation(s)
- Sophie Uzureau
- Facultés Universitaires Notre-Dame de la Paix, Unité de Recherche en Biologie Moléculaire, Laboratoire d'Immunologie-Microbiologie, rue de Bruxelles 61, 5000-Namur, Belgium
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Dhand A, Ross JJ. Implantable cardioverter-defibrillator infection due to Brucella melitensis: case report and review of brucellosis of cardiac devices. Clin Infect Dis 2007; 44:e37-9. [PMID: 17243046 DOI: 10.1086/511079] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2006] [Accepted: 11/08/2006] [Indexed: 11/03/2022] Open
Abstract
We report a case of implantable cardioverter-defibrillator infection due to Brucella melitensis and review 5 previously reported cases of Brucella infection of cardiac devices. Device removal, followed by antibiotic therapy for 6 weeks, is probably required for cure. Although rare, reports of Brucella infection of prosthetic implants and devices have increased in the past decade. Brucellosis should be considered in the differential diagnosis of cardiac device infection in patients residing in or traveling to areas of endemicity.
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Affiliation(s)
- Abhay Dhand
- Division of Geographic Medicine and Infectious Diseases, Tufts-New England Medical Center, Boston, Massachusetts
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49
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Castañeda-Roldán EI, Ouahrani-Bettache S, Saldaña Z, Avelino F, Rendón MA, Dornand J, Girón JA. Characterization of SP41, a surface protein of Brucella associated with adherence and invasion of host epithelial cells. Cell Microbiol 2006; 8:1877-87. [PMID: 16817909 DOI: 10.1111/j.1462-5822.2006.00754.x] [Citation(s) in RCA: 57] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Brucella is an invasive organism that multiplies and survives within eukaryotic cells. The brucellae are able to adhere to the surface of cultured epithelial cells, a mechanism that may facilitate penetration and dissemination to other host tissues. However, no adhesins that allow the bacteria to interact with the surface of epithelial cells before migration within polymorphonuclear leukocytes, monocytes and macrophages have been described. Here, we show that Brucella surface proteins (SPs) with apparent molecular masses of 14, 18 and 41 kDa bound selectively to HeLa cells. However, only antibodies directed against the 41 kDa surface protein (SP41) inhibited in dose-response manner, bacterial adherence and invasion of HeLa cells. HeLa cells treated with neuraminidase did not bind SP41, suggesting the involvement of cellular sialic acid residues in this interaction. Biochemical analysis of SP41 revealed that this protein is the predicted product of the ugpB locus, which showed significant homology to the glycerol-3-phosphate-binding ATP-binding cassette (ABC) transporter protein found in several bacterial species. SP41 appears to be exposed on the bacterial surface as determined by immunofluorescence and immunogold labelling with anti-SP41 antibody. An isogenic DeltaugpB mutant showed a significant inhibitory effect on Brucella adherence and invasion of human cultured epithelial cells and this effect could be reversed by restoration of the ugpB on a plasmid. Lastly, we also show that most of the sera from individuals with acute brucellosis, but not sera obtained from healthy donors or patients with chronic brucellosis, mount antibody reactivity against SP41, suggesting that this protein is produced in vivo and that it elicits an antibody immune response. These data are novel findings that offer new insights into understanding the interplay between this bacterium and host target cells, and identify a new target for vaccine development and prevention of brucellosis.
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Affiliation(s)
- Elsa I Castañeda-Roldán
- Centro de Investigaciones en Ciencias Microbiológicas, Benemérita Universidad Autónoma de Puebla, Ciudad Universitaria, Puebla 72570, México
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Fontes P, Alvarez-Martinez MT, Gross A, Carnaud C, Köhler S, Liautard JP. Absence of evidence for the participation of the macrophage cellular prion protein in infection with Brucella suis. Infect Immun 2005; 73:6229-36. [PMID: 16177294 PMCID: PMC1230949 DOI: 10.1128/iai.73.10.6229-6236.2005] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Brucella spp. are stealthy bacteria that enter host cells without major perturbation. The molecular mechanism involved is still poorly understood, although numerous studies have been published on this subject. Recently, it was reported that Brucella abortus utilizes cellular prion protein (PrP(C)) to enter the cells and to reach its replicative niche. The molecular mechanisms involved were not clearly defined, prompting us to analyze this process using blocking antibodies against PrP(C). However, the behavior of Brucella during cellular infection under these conditions was not modified. In a next step, the behavior of Brucella in macrophages lacking the prion gene and the infection of mice knocked out for the prion gene were studied. We observed no difference from results obtained with the wild-type control. Although some contacts between PrP(C) and Brucella were observed on the surface of the cells by using confocal microscopy, we could not show that Brucella specifically bound recombinant PrP(C). Therefore, we concluded from our results that prion protein (PrP(C)) was not involved in Brucella infection.
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