Project description:Through a system-level analysis of non-essential two-component signal transduction systems (TCS) genes in Brucella ovis, we have discovered that deletion of an HWE histidine kinase, BOV_1602, leads to significant increase in resistance to SDS detergent and other anionic or zwitterionic detergents. To better understand this detergent resistance phenotype, we performed RNA-seq experiment using both WT and ∆BOV_1602 cultured on no stress (TASB) or TSAB supplemented with 0.004% SDS.
Project description:Brucella dynamically engage macrophages while trafficking to an intracellular replicative niche as macrophages, the first line of innate host defense, attempt to eliminate organisms. Brucella melitensis, B. neotomae, and B. ovis are highly homologous, yet exhibit a range of host pathogenicity and specificity. RAW 264.7 macrophages infected with B. melitensis, and B. ovis exhibit divergent patterns of bacterial persistence and clearance; conversely, B. melitensis and B. neotomae exhibit similar patterns of infection. Evaluating early macrophage interaction with Brucella spp. allows discovery of host entry and intracellular translocation mechanisms, rather than bacterial replication. Microarray analysis of macrophage transcript levels following a 4 hr Brucella spp. infection revealed 130 probe sets altered compared to uninfected macrophages; specifically, 72 probe sets were increased and 58 probe sets were decreased with any Brucella spp. Interestingly, much of the inflammatory response was not regulated by the number of Brucella gaining intracellular entry, as macrophage transcript levels were often equivalent among B. melitensis, B. ovis, and B. neotomae infections. An additional 33 probe sets were identified with altered macrophage transcript levels among Brucella spp. infections that may correlate with species specific host defenses and intracellular survival. Gene ontological categorization unveiled genes altered among species are involved in cell growth and maintenance, response to external stimuli, transcription regulation, transporter activity, endopeptidase inhibitor activity and G-protein mediated signaling. Host transcript profiles provide a foundation to understand variations in Brucella spp. infections, while structure of the macrophage response and intracellular niche of Brucella spp. will be revealed through piecewise consideration of host signaling pathways. Keywords: Macrophage, intracellular pathogen, Brucella melitensis, Brucella neotomae, Brucella ovis, inflammatory immune response, species specificity
Project description:This SuperSeries is composed of the following subset Series: GSE35612: Microarray analysis of gene expression in rams experimentally infected with a rough virulent strain of Brucella ovis (acute phase) GSE35613: Microarray analysis of gene expression in rams experimentally infected with a rough virulent strain of Brucella ovis (chronic 1 phase) GSE35614: Microarray analysis of gene expression in rams experimentally infected with a rough virulent strain of Brucella ovis (chronic 2 phase) Refer to individual Series
Project description:Wild-type Brucella ovis ATCC 25840 requires the addition of 5% CO2 to the atmosphere to grow on either nutrient agar plates or in liquid broth culture. The goal of this study was to measure the transcriptional response of two Brucella ovis strains under high (5%) and low (0.04%) CO2. The two strains assayed were 1) wild-type and 2) a spontaneous mutant that can be cultivated in standard atmospheric levels of CO2 (~0.04%). Wild-type B. ovis harbors a single nucleotide insertion at the 3' end of a beta carbonic anhydrase gene, bcaA, which renders it non-functional. The spontaneous mutant lost this nucleotide insertion, which restored the consensus reading frame and results in a functional BcaA protein.
Project description:Infection of sheep with Brucella ovis results in ovine brucellosis, a disease characterized by infertility in rams, abortion in ewes and increased perinatal mortality in lambs. During the course of the infection both the ovine immune response and host cell gene expression are modified. The objective of this research was to conduct a preliminary characterization of differential gene expression in rams experimentally infected with B. ovis by microarray hybridization and real-time RT-PCR.
Project description:Infection of sheep with Brucella ovis results in ovine brucellosis, a disease characterized by infertility in rams, abortion in ewes and increased perinatal mortality in lambs. During the course of the infection both the ovine immune response and host cell gene expression are modified. The objective of this research was to conduct a preliminary characterization of differential gene expression in rams experimentally infected with B. ovis by microarray hybridization and real-time RT-PCR. Six hybridizations were conducted using total RNA from three individual infected sheep at 15 and 60 days post infection. In each comparison, the control channels contained total RNA from each of the same three sheep at 0 days post infection. Ratios were calculated as B. ovis-infected sheep at 15 and 60 dpc versus uninfected animals at 0 dpc.
Project description:Brucella ovis causes an important disease characterized by decreased fertility in rams, sporadic abortions in ewes and increased lamb mortality. The live attenuated B. melitensis Rev.1 vaccine is considered the best vaccine available against this infection. However, this vaccine shows variable protective efficacy ranging from 40% to 100%.The objective of this study was to identify possible correlates of protective response to B. ovis infection through the characterization by microarray hybridization and real-time RT-PCR of inflammatory and immune response genes upregulated in rams previously immunized with the B. melitensis Rev 1 vaccine strain and experimentally challenged with B. ovis. Gene expression profiles were compared before and after challenge with B. ovis between rams protected and those vaccinated but found infected after challenge. The genes upregulated in vaccinated and protected rams provide possible correlates of protective response to B. ovis infection in rams immunized with the B. melitensis Rev 1 vaccine.
Project description:The study demonstrated the gene expression through microarray analysis of total mRNA in rams experimentally infected with a rough (R) virulent strain of Brucella ovis in reproductive organs (epididymus, testicles, ampolae, vesicular glands, bulbourethral glands) and a pool of lymph nodes (inguinal and scrotal) at three different times: acute phase (60 days post challenge [dpc]), chronic phase 1 (120dpc), and chronic phase 2 (240dpc) of infection. To further define the gene expression changes associated with infected rams, the profiles of a control group (0 dpc) of rams was compared using the Affymetrix Bovine Genome Array. Of the 23,000 genes that were analyzed on the array, B. ovis infection in rams’ tissues revealed 139, 930 and 744 Differentially Expressed Genes (DEGs) in the acute, chronic 1, and chronic phase 2 of infection, respectively. Among the three phases of infection, 44 DEGs (30 known and 14 unknown genes) were expressed in common. The biological functions of immune cell trafficking, immunological disease, infectious disease, inflammatory disease, inflammatory response and cellular movement were significant at the three phases of infection. The results support the first microarray analysis of ram tissues infected with an R strain of B. ovis.
Project description:The study demonstrated the gene expression through microarray analysis of total mRNA in rams experimentally infected with a rough (R) virulent strain of Brucella ovis in reproductive organs (epididymus, testicles, ampolae, vesicular glands, bulbourethral glands) and a pool of lymph nodes (inguinal and scrotal) at three different times: acute phase (60 days post challenge [dpc]), chronic phase 1 (120dpc), and chronic phase 2 (240dpc) of infection. To further define the gene expression changes associated with infected rams, the profiles of a control group (0 dpc) of rams was compared using the Affymetrix Bovine Genome Array. Of the 23,000 genes that were analyzed on the array, B. ovis infection in rams’ tissues revealed 139, 930 and 744 Differentially Expressed Genes (DEGs) in the acute, chronic 1, and chronic phase 2 of infection, respectively. Among the three phases of infection, 44 DEGs (30 known and 14 unknown genes) were expressed in common. The biological functions of immune cell trafficking, immunological disease, infectious disease, inflammatory disease, inflammatory response and cellular movement were significant at the three phases of infection. The results support the first microarray analysis of ram tissues infected with an R strain of B. ovis.
Project description:The study demonstrated the gene expression through microarray analysis of total mRNA in rams experimentally infected with a rough (R) virulent strain of Brucella ovis in reproductive organs (epididymus, testicles, ampolae, vesicular glands, bulbourethral glands) and a pool of lymph nodes (inguinal and scrotal) at three different times: acute phase (60 days post challenge [dpc]), chronic phase 1 (120dpc), and chronic phase 2 (240dpc) of infection. To further define the gene expression changes associated with infected rams, the profiles of a control group (0 dpc) of rams was compared using the Affymetrix Bovine Genome Array. Of the 23,000 genes that were analyzed on the array, B. ovis infection in rams’ tissues revealed 139, 930 and 744 Differentially Expressed Genes (DEGs) in the acute, chronic 1, and chronic phase 2 of infection, respectively. Among the three phases of infection, 44 DEGs (30 known and 14 unknown genes) were expressed in common. The biological functions of immune cell trafficking, immunological disease, infectious disease, inflammatory disease, inflammatory response and cellular movement were significant at the three phases of infection. The results support the first microarray analysis of ram tissues infected with an R strain of B. ovis.