1
|
Guo J, Deng X, Zhang Y, Song S, Zhao T, Zhu D, Cao S, Baryshnikov PI, Cao G, Blair HT, Chen C, Gu X, Liu L, Zhang H. The Flagellar Transcriptional Regulator FtcR Controls Brucella melitensis 16M Biofilm Formation via a betI-Mediated Pathway in Response to Hyperosmotic Stress. Int J Mol Sci 2022; 23:ijms23179905. [PMID: 36077302 PMCID: PMC9456535 DOI: 10.3390/ijms23179905] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Revised: 08/26/2022] [Accepted: 08/27/2022] [Indexed: 11/16/2022] Open
Abstract
The expression of flagellar proteins in Brucella species likely evolved through genetic transference from other microorganisms, and contributed to virulence, adaptability, and biofilm formation. Despite significant progress in defining the molecular mechanisms behind flagellar gene expression, the genetic program controlling biofilm formation remains unclear. The flagellar transcriptional factor (FtcR) is a master regulator of the flagellar system’s expression, and is critical for B. melitensis 16M’s flagellar biogenesis and virulence. Here, we demonstrate that FtcR mediates biofilm formation under hyperosmotic stress. Chromatin immunoprecipitation with next-generation sequencing for FtcR and RNA sequencing of ftcR-mutant and wild-type strains revealed a core set of FtcR target genes. We identified a novel FtcR-binding site in the promoter region of the osmotic-stress-response regulator gene betI, which is important for the survival of B. melitensis 16M under hyperosmotic stress. Strikingly, this site autoregulates its expression to benefit biofilm bacteria’s survival under hyperosmotic stress. Moreover, biofilm reduction in ftcR mutants is independent of the flagellar target gene fliF. Collectively, our study provides new insights into the extent and functionality of flagellar-related transcriptional networks in biofilm formation, and presents phenotypic and evolutionary adaptations that alter the regulation of B. melitensis 16M to confer increased tolerance to hyperosmotic stress.
Collapse
Affiliation(s)
- Jia Guo
- State International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
| | - Xingmei Deng
- State International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
| | - Yu Zhang
- State International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
| | - Shengnan Song
- State International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
| | - Tianyi Zhao
- State International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
| | - Dexin Zhu
- State International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
| | - Shuzhu Cao
- State International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
| | - Peter Ivanovic Baryshnikov
- State International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
- College of Veterinary, Altai State Agricultural University, 656000 Barnaul, Russia
| | - Gang Cao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan 430000, China
| | - Hugh T. Blair
- State International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
- International Sheep Research Center, School of Agriculture and Environment, Massey University, Palmerston North 4442, New Zealand
| | - Chuangfu Chen
- State International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
| | - Xinli Gu
- State International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
| | - Liangbo Liu
- State International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
- Correspondence: (L.L.); (H.Z.); Tel.: +86-0993-2057971 (L.L. & H.Z.)
| | - Hui Zhang
- State International Joint Research Center for Animal Health Breeding, College of Animal Science and Technology, Shihezi University, Shihezi 832003, China
- Correspondence: (L.L.); (H.Z.); Tel.: +86-0993-2057971 (L.L. & H.Z.)
| |
Collapse
|
2
|
Coloma-Rivero RF, Flores-Concha M, Molina RE, Soto-Shara R, Cartes Á, Oñate ÁA. Brucella and Its Hidden Flagellar System. Microorganisms 2021; 10:83. [PMID: 35056531 PMCID: PMC8781033 DOI: 10.3390/microorganisms10010083] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Revised: 12/21/2021] [Accepted: 12/28/2021] [Indexed: 01/18/2023] Open
Abstract
Brucella, a Gram-negative bacterium with a high infective capacity and a wide spectrum of hosts in the animal world, is found in terrestrial and marine mammals, as well as amphibians. This broad spectrum of hosts is closely related to the non-classical virulence factors that allow this pathogen to establish its replicative niche, colonizing epithelial and immune system cells, evading the host's defenses and defensive response. While motility is the primary role of the flagellum in most bacteria, in Brucella, the flagellum is involved in virulence, infectivity, cell growth, and biofilm formation, all of which are very important facts in a bacterium that to date has been described as a non-motile organism. Evidence of the expression of these flagellar proteins that are present in Brucella makes it possible to hypothesize certain evolutionary aspects as to where a free-living bacterium eventually acquired genetic material from environmental microorganisms, including flagellar genes, conferring on it the ability to reach other hosts (mammals), and, under selective pressure from the environment, can express these genes, helping it to evade the immune response. This review summarizes relevant aspects of the presence of flagellar proteins and puts into context their relevance in certain functions associated with the infective process. The study of these flagellar genes gives the genus Brucella a very high infectious versatility, placing it among the main organisms in urgent need of study, as it is linked to human health by direct contact with farm animals and by eventual transmission to the general population, where flagellar genes and proteins are of great relevance.
Collapse
Affiliation(s)
| | | | | | | | | | - Ángel A. Oñate
- Laboratory of Molecular Immunology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepción, Concepción 4030000, Chile; (R.F.C.-R.); (M.F.-C.); (R.E.M.); (R.S.-S.); (Á.C.)
| |
Collapse
|
3
|
Whatmore AM, Foster JT. Emerging diversity and ongoing expansion of the genus Brucella. INFECTION GENETICS AND EVOLUTION 2021; 92:104865. [PMID: 33872784 DOI: 10.1016/j.meegid.2021.104865] [Citation(s) in RCA: 32] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2021] [Revised: 04/12/2021] [Accepted: 04/14/2021] [Indexed: 12/15/2022]
Abstract
Remarkable genetic diversity and breadth of host species has been uncovered in the Brucella genus over the past decade, fundamentally changing our concept of what it means to be a Brucella. From ocean fishes and marine mammals, to pond dwelling amphibians, forest foxes, desert rodents, and cave-dwelling bats, Brucella have revealed a variety of previously unknown niches. Classical microbiological techniques have been able to help us classify many of these new strains but at times have limited our ability to see the true relationships among or within species. The closest relatives of Brucella are soil bacteria and the adaptations of Brucella spp. to live intracellularly suggest that the genus has evolved to live in vertebrate hosts. Several recently discovered species appear to have phenotypes that are intermediate between soil bacteria and core Brucella, suggesting that they may represent ancestral traits that were subsequently lost in the traditional species. Remarkably, the broad relationships among Brucella species using a variety of sequence and fragment-based approaches have been upheld when using comparative genomics with whole genomes. Nonetheless, genomes are required for fine-scale resolution of many of the relationships and for understanding the evolutionary history of the genus. We expect that the coming decades will reveal many more hosts and previously unknown diversity in a wide range of environments.
Collapse
Affiliation(s)
- Adrian M Whatmore
- OIE and FAO Brucellosis Reference Laboratory, Department of Bacteriology, Animal and Plant Health Agency (APHA), Woodham Lane, Addlestone, Surrey, United Kingdom.
| | - Jeffrey T Foster
- Pathogen and Microbiome Institute, Northern Arizona University, Flagstaff, AZ, USA
| |
Collapse
|
4
|
Coloma-Rivero RF, Gómez L, Alvarez F, Saitz W, Del Canto F, Céspedes S, Vidal R, Oñate AA. The Role of the Flagellar Protein FlgJ in the Virulence of Brucella abortus. Front Cell Infect Microbiol 2020; 10:178. [PMID: 32411617 PMCID: PMC7198779 DOI: 10.3389/fcimb.2020.00178] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Accepted: 04/03/2020] [Indexed: 12/28/2022] Open
Abstract
Brucella abortus is a facultative intracellular pathogen that causes a zoonosis called brucellosis. This disease leads to abortion and infertility in cattle, and diverse complications in humans. B. abortus is a successful intracellular bacterium that has developed the ability to evade the host's immune system and it replicates in professional and non-professional phagocytic cells, persisting in the different tissues, and organs of its hosts. It has been described that Brucella expresses a polar flagellum under certain conditions, but its function is still unknown. In this study we evaluated the role of the FlgJ, a protein, presumably a peptidoglycan hydrolase involved in flagellum formation and in the virulence of B. abortus strain 2308. B. abortus 2308 ΔflgJ mutant and complemented strains were constructed to study the function of the FlgJ protein in the context of the virulence of this pathogen in in vitro and in vivo assays. The results showed that the elimination of the flgJ gene delays the growth rate of B. abortus in culture, reduces its intracellular survival capacity in professional and non-professional phagocytic cells, rendering it unable to escape from the endocytic route and not reaching the endoplasmic reticulum. It also negatively affects their persistence in BALB/c mice. Functionally, the B. abortus 2308 flgJ gene restored motility to an E. coli flgJ mutant gene. Furthermore, it was discovered that the production of FlgJ protein is associated with the bacterial adherence by B. abortus. Therefore, although the specific function of the polar flagellum for Brucella is unknown, the data indicates that the flagellar flgJ gene and its product are required for full virulence of B. abortus 2308, since its deletion significantly reduces the fitness of this pathogen in vitro and in vivo.
Collapse
Affiliation(s)
- Roberto F Coloma-Rivero
- Laboratory of Molecular Immunology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepción, Concepción, Chile
| | - Leonardo Gómez
- Laboratory of Molecular Immunology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepción, Concepción, Chile
| | - Francisco Alvarez
- Laboratory of Molecular Immunology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepción, Concepción, Chile
| | - Waleska Saitz
- Laboratory of Molecular Immunology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepción, Concepción, Chile.,Microbiology and Mycology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Felipe Del Canto
- Microbiology and Mycology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Sandra Céspedes
- Laboratory of Molecular Immunology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepción, Concepción, Chile.,Microbiology and Mycology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Roberto Vidal
- Microbiology and Mycology Program, Institute of Biomedical Sciences, Faculty of Medicine, University of Chile, Santiago, Chile
| | - Angel A Oñate
- Laboratory of Molecular Immunology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepción, Concepción, Chile
| |
Collapse
|
5
|
Sanogo M, Fretin D, Thys E, Saegerman C. Exploring the Diversity of Field Strains of Brucella abortus Biovar 3 Isolated in West Africa. Front Microbiol 2017; 8:1232. [PMID: 28713359 PMCID: PMC5491933 DOI: 10.3389/fmicb.2017.01232] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2016] [Accepted: 06/19/2017] [Indexed: 12/22/2022] Open
Abstract
Brucellosis is one of the most widespread bacterial zoonotic diseases in the world, affecting both humans and domestic and wild animals. Identification and biotyping of field strains of Brucella are of key importance for a better knowledge of the epidemiology of brucellosis, for identifying appropriate antigens, for managing disease outbreaks and for setting up efficient preventive and control programmes. Such data are required both at national and regional level to assess potential threats for public health. Highly discriminative genotyping methods such as the multiple locus variable number of tandem repeats analysis (MLVA) allow the comparison and assessment of genetic relatedness between field strains of Brucella within the same geographical area. In this study, MLVA biotyping data retrieved from the literature using a systematic review were compared using a clustering analysis and the Hunter-Gaston diversity index (HGDI). Thus, the analysis of the 42 MLVA genotyping results found in the literature on West Africa [i.e., from Ivory Coast (1), Niger (1), Nigeria (34), The Gambia (3), and Togo (3)] did not allow a complete assessment of the actual diversity among field strains of Brucella. However, it provided some preliminary indications on the co-existence of 25 distinct genotypes of Brucella abortus biovar 3 in this region with 19 genotypes from Nigeria, three from Togo and one from Ivory Coast, The Gambia, and Niger. The strong and urgent need for more sustainable molecular data on prevailing strains of Brucella in this sub-region of Africa and also on all susceptible species including humans is therefore highlighted. This remains a necessary stage to allow a comprehensive understanding of the relatedness between field strains of Brucella and the epidemiology of brucellosis within West Africa countries.
Collapse
Affiliation(s)
- Moussa Sanogo
- Central Veterinary Laboratory of Bingerville, LANADABingerville, Ivory Coast
| | - David Fretin
- Department of Bacteriology and Immunology, Veterinary and Agro-chemical Research CentreBrussels, Belgium
| | - Eric Thys
- Department of Biomedical Sciences, Institute of Tropical MedicineAntwerp, Belgium
| | - Claude Saegerman
- Research Unit of Epidemiology and Risk Analysis Applied to Veterinary Sciences (UREAR-ULg), Faculty of Veterinary Medicine, Fundamental and Applied Research for Animal and Health Center, University of LiègeLiège, Belgium
| |
Collapse
|
6
|
Brucella abortus: Current Research and Future Trends. CURRENT CLINICAL MICROBIOLOGY REPORTS 2017. [DOI: 10.1007/s40588-017-0052-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
7
|
Ducrotoy M, Bertu W, Matope G, Cadmus S, Conde-Álvarez R, Gusi A, Welburn S, Ocholi R, Blasco J, Moriyón I. Brucellosis in Sub-Saharan Africa: Current challenges for management, diagnosis and control. Acta Trop 2017; 165:179-193. [PMID: 26551794 DOI: 10.1016/j.actatropica.2015.10.023] [Citation(s) in RCA: 126] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2015] [Revised: 09/14/2015] [Accepted: 10/29/2015] [Indexed: 02/04/2023]
Abstract
Brucellosis is a highly contagious zoonosis caused by bacteria of the genus Brucella and affecting domestic and wild mammals. In this paper, the bacteriological and serological evidence of brucellosis in Sub-Saharan Africa (SSA) and its epidemiological characteristics are discussed. The tools available for the diagnosis and treatment of human brucellosis and for the diagnosis and control of animal brucellosis and their applicability in the context of SSA are presented and gaps identified. These gaps concern mostly the need for simpler and more affordable antimicrobial treatments against human brucellosis, the development of a B. melitensis vaccine that could circumvent the drawbacks of the currently available Rev 1 vaccine, and the investigation of serological diagnostic tests for camel brucellosis and wildlife. Strategies for the implementation of animal vaccination are also discussed.
Collapse
|
8
|
Phenotypic and genotypic characterization of Brucella strains isolated from autochthonous livestock reveals the dominance of B. abortus biovar 3a in Nigeria. Vet Microbiol 2015; 180:103-8. [DOI: 10.1016/j.vetmic.2015.08.014] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 07/30/2015] [Accepted: 08/14/2015] [Indexed: 12/31/2022]
|
9
|
Mathew C, Stokstad M, Johansen TB, Klevar S, Mdegela RH, Mwamengele G, Michel P, Escobar L, Fretin D, Godfroid J. First isolation, identification, phenotypic and genotypic characterization of Brucella abortus biovar 3 from dairy cattle in Tanzania. BMC Vet Res 2015. [PMID: 26195218 PMCID: PMC4508816 DOI: 10.1186/s12917-015-0476-8] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
BACKGROUND Brucellosis is a disease of worldwide public health and economic importance. Successful control is based on knowledge of epidemiology and strains present in an area. In developing countries, most investigations are based on serological assays. This study aimed at investigating a dairy herd experiencing abortions in order to establish within-herd seroprevalence to Brucella spp., identify, characterize Brucella strains by Multiple Loci Variable Number of Tandem Repeats Analysis (MLVA-VNTR) and investigate possible spillover to other species. RESULTS The within-herd seroprevalence in cattle (n = 200) was 48 % (95 % CI 41-55), using an indirect ELISA, while the Rose Bengal Test (RBT) yielded lower prevalence (21.5 %; 95 % CI 16-27). Two sheep (n = 35) and one goat (n = 50) were seropositive using ELISA while none of the dogs (n = 6) was positive with the RBT. Three Brucella were isolated from an aborted fetus and associated membranes. Real time PCR (IS711), Bruce-ladder and classical biotyping classified the isolates as B. abortus biovar 3. MLVA-VNTR revealed two different but closely related genotypes. The isolates showed unique profiles, providing the first genotypic data from Tanzania. These genotypes were not related to B. abortus biovar 3 reference strain Tulya originally isolated from a human patient in Uganda in 1958, unlike the genotypes isolated and characterized recently in Kenya. High within-herd prevalence, isolation of the pathogen and abortion confirm that B. abortus is circulating in this herd with cattle as reservoir hosts. A low seroprevalence in sheep and goats suggests a spillover of B. abortus from cattle to small ruminants in the herd. CONCLUSIONS This is the first isolation and characterization of B. abortus biovar 3 from a dairy cow with abortion in Tanzania. The origin of the Tanzanian genotypes remain elusive, although they seem to be related to genotypes found in Europe, Turkey and China but not related to B. abortus biovar 3 reference strain or genotypes from Kenya. Importantly, replacement heifers are commonly sourced from large farms like this to smallholder farmers, which poses risk of spread of bacteria to other herds. B. abortus is a significant zoonotic risk and animal health problem in this production system, therefore further studies on humans is recommended.
Collapse
Affiliation(s)
- C Mathew
- Department of Production Animals Clinical Sciences, Norwegian University of Life Science, Oslo, Norway. .,Sokoine University of Agriculture, Morogoro, Tanzania.
| | - M Stokstad
- Department of Production Animals Clinical Sciences, Norwegian University of Life Science, Oslo, Norway.
| | | | - S Klevar
- National Veterinary Institute, Oslo, Norway.
| | - R H Mdegela
- Sokoine University of Agriculture, Morogoro, Tanzania.
| | - G Mwamengele
- Sokoine University of Agriculture, Morogoro, Tanzania.
| | - P Michel
- Veterinary and Agrochemical Research Center, Brussels, Belgium.
| | - L Escobar
- Veterinary and Agrochemical Research Center, Brussels, Belgium.
| | - D Fretin
- Veterinary and Agrochemical Research Center, Brussels, Belgium.
| | - J Godfroid
- Department of Arctic and Marine Biology, University of Tromsø - the Arctic University of Norway, Faculty of Biosciences, Fisheries and Economics, Research Group of Arctic Infection Biology, Langnes, Postbox 6050, 9037, Tromsø, Norway.
| |
Collapse
|