Project description:Brucella canis is a facultative intracellular pathogen that preferentially infects members of the Canidae family. Here, we report the genome sequencing of two Brucella canis strains isolated from humans and one isolated from a dog host.
Project description:In China, brucellosis is an endemic disease typically caused by Brucella melitensis infection (biovars 1 and 3). Brucella canis infection in dogs has not traditionally recognized as a major problem. In recent years however, brucellosis resulting from Brucella canis infection has also been reported, suggesting that infections from this species may be increasing. Data concerning the epidemiology of brucellosis resulting from Brucella canis infection is limited. Therefore, the purpose of this study was to assess the diversity among Chinese Brucella canis strains for epidemiological purposes. First, we employed a 16-marker VNTR assay (Brucella MLVA-16) to assess the diversity and epidemiological relationship of 29 Brucella canis isolates from diverse locations throughout China with 38 isolates from other countries. MLVA-16 analysis separated the 67 Brucella canis isolates into 57 genotypes that grouped into five clusters with genetic similarity coefficients ranging from 67.73 to 100%. Moreover, this analysis revealed a new genotype (2-3-9-11-3-1-5-1:118), which was present in two isolates recovered from Guangxi in 1986 and 1987. Second, multiplex PCR and sequencing analysis were used to determine whether the 29 Chinese Brucella canis isolates had the characteristic BMEI1435 gene deletion. Only two isolates had this deletion. Third, amplification of the omp25 gene revealed that 26 isolates from China had a T545C mutation. Collectively, this study reveals that considerable diversity exists among Brucella canis isolates in China and provides resources for studying the genetic variation and microevolution of Brucella.
Project description:Canine brucellosis is a major underestimated zoonosis that remains endemic in many areas of the world. A recent phylogeographic investigation including 53 Brucella canis field isolates revealed the existence of two major lineages worldwide. Here, we report genome sequencing of 5 representative isolates of different clades identified in this study.
Project description:Brucella canis infects several species of animals, and canine is the preferred host. Genome sequences of strains from different hosts are valuable for comparative analysis of host adaptation and microevolution. Here, we report the genome sequence of Brucella canis strain 118, a strain isolated from canine.
Project description:Brucella canis is considered a rare cause of human brucellosis because of difficulties in presumptive diagnosis and underestimation of the incidence. Here, we report the draft genome sequence of a Brucella canis isolate, BCB018, isolated from a human patient, providing precious resources for comparative genomics analysis of Brucella field strains.
Project description:Gram-negative bacteria release nanovesicles, called outer membrane vesicles (OMVs), from their outer membrane. Proteomics has been used to determine their composition. OMVs contain proteins able to elicit an immune response, so they have been proposed as a model to develop acellular vaccines. In this study, OMVs of Brucella suis, B. ovis, B. canis, and B. neotomae were purified and analyzed by SDS-PAGE, transmission electron microscopy and liquid chromatography coupled to mass spectrometry to determine the pan-proteome of these vesicles. In addition, antigenic proteins were detected by western blot with anti-Brucella sera. The in silico analysis of the pan-proteome revealed many homologous proteins, such as Omp16, Omp25, Omp31, SodC, Omp2a, and BhuA. Proteins contained in the vesicles from different Brucella species were detected by anti-Brucella sera. The occurrence of previously described immunogenic proteins derived from OMVs supports the use of these vesicles as candidates to be evaluated as an acellular brucellosis vaccine.
Project description:Brucella spp. are facultative intracellular pathogens and zoonotic agents which pose a great threat to human health. Twelve different Brucella species have been identi?ed to date. Here, we report the complete genome sequence of a Brucella canis GB1 strain, which contains two circular chromosomes of 3,277,308?bp in total.
Project description:BACKGROUND:Canine brucellosis, due to Brucella canis, is a worldwide zoonosis that remains endemic in South America, including Brazil. Implementation of powerful whole-genome sequencing approaches allowed exploring the Brucella genus considered as monomorphic, with, to date, more than 500 genomes available in public databases. Nevertheless, with under-representation of B. canis genomes -only twenty complete or draft genomes-, lack of knowledge about this species is still considerable. This report describes a comparative genomics-based phylogeographic investigation of 53 B. canis strains, including 28 isolates paired-end sequenced in this work. RESULTS:Obtained results allow identifying a SNP panel species-specific to B. canis of 1086 nucleotides. In addition, high-resolution analyses assess the epidemiological relationship between worldwide isolates. Our findings show worldwide strains are distributed among 2 distinct lineages. One of them seems to be specific to South American strains, including Brazil. B. canis South American strains may be identified by a SNP panel of 15 nucleotides, whereas a 22 SNP panel is sufficient to define contamination origin from Brazil. These results lead to the proposal of a possible spread route for dog brucellosis through South America. Additionally, whole-genome analyses highlight the remarkable genomic stability of B. canis strains over time and the sustainability of the infection in São Paulo over 12 year-period. CONCLUSIONS:Significant increase of B. canis genomes available in public databases provides new insights into B. canis infection in South America, including Brazil, as well as in the world, and also offers new perspectives for the Brucella genus largo sensu.
Project description:Canine brucellosis, caused by Brucella canis, is a disease of dogs and represents a public health concern as it can be transmitted to humans. Canine brucellosis is on the rise in the United States and there is currently no vaccine for use in dogs. Mice have been extensively utilized to investigate host-pathogen interactions and vaccine candidates for smooth Brucella species and could serve a similar role for studying B. canis. However, comparatively little is known about B. canis infection in mice. The objective of this study was to characterize the kinetics of colonization and pathogenicity of B. canis in mice in order to evaluate the mouse as a model for studying this pathogen. C57BL/6 mice were inoculated intraperitoneally with 105, 107, or 109 CFU of Brucella canis RM6/66 and euthanized 1-, 2-, 4-, 6-, 9-, and 12-weeks post-inoculation. B. canis induced splenomegaly in mice infected with 109 CFU at 1- and 2 weeks post-inoculation while no gross lesions were observed in other dose groups. Infection at the two higher doses resulted in dose-dependent granulomatous hepatitis and histiocytic infiltration of the spleen and mesenteric lymph nodes by 1-2 weeks. B. canis was cultured from the liver, spleen, uterus, bone marrow, lung, and kidney in all groups with colonization declining at a slow but steady rate throughout the experiment. Clearance was achieved by 9 weeks 105 CFU group and by 12 weeks in the 107 CFU group, while B. canis persisted in the spleen until 12 weeks in the highest dose group. Although B. canis does not demonstrate significant replication in C57BL/6 mice, it has the ability to establish an infection, induce splenomegaly, and persist for several weeks in multiple organs. Moreover, 1 x 107 CFU appears to be a suitable challenge dose for investigating vaccine safety.
Project description:This is a report of whole-genome sequences of a Brucella abortus strain and two Brucella suis strains isolated from bovine in Zimbabwe. These strains were selected based on their origin and data obtained when using multiplex PCR assays, then sequenced using next-generation sequencing technologies.