Project description:Streptococcus suis is an important zoonotic pathogen that can cause meningitis and sepsis in both pigs and humans. In this study,we evaluated the genetic difference of 40 Streptococcus suis strains belonging to various sequence types by comparative genomic hybridization to identify genes associated with the variation in pathogenicity using NimbleGen’s tilling microarray platform. Application of Comparative Phylogenomics to Identify Genetic Differences Relating to Pathogenicity of Streptococcus suis
Project description:Streptococcus suis serotype 2 is an important pathogen of pigs, and the disease it causes is characterized by meningitis, septicaemia and pneumonia with high mortality. The pathogen is also an emerging zoonotic agent and threatens humans that are exposed to pigs or their by-products. We investigated the response of PBMC (Peripheral Blood Mononuclear Cell), brain and lung tissues to infection with S. suis 2 strain SC19 by using the Affymetrix Porcine Genome Array.
Project description:Identification of Genes and Genomic Islands Correlated with High Pathogenicity through Tilling Microarray-Based Comparative Genomics in S. suis. Streptococcus suis is an important zoonotic pathogen that can cause meningitis and sepsis in both pigs and humans. S. suis isolates have been categorized into groups of different levels of pathogenicity, with sequence type (ST) ST1 clonal complex strains having a higher degree of virulence than other STs. However, the genetic basis of the differences in pathogenicity is still poorly understood. In this study, a comprehensive genomic comparison of 31 S. suis strains from different clinical sources with the genome sequence of the high pathogenicity (HP) strain GZ1 was conducted using NimbleGen’s tilling microarray platform.
Project description:Streptococcus suis is an important emerging worldwide pig pathogen and zoonotic agent with rapid evolution of virulence and drug resistance. Licochalcone A, used in traditional Chinese medicine, exhibits antimicrobial, antioxidant and anti-inflammatory activities. Herein, a whole-genome DNA microarray was used to investigate the global transcriptional regulation of Streptococcus suis 05ZYH33 treated by subinhibitory concentration of licochalcone A. 132 genes were differentially regulated upon liochalcone A treatment, including 78 genes up-regulated and 54 genes down-regulated which included many central biological functions such as metabolism, transcription and translation. We tried to investigate the antimicrobial mechanism of licochalcone A in the aspect of bacterial cell cycle control. Our analysis indicated that licochalcone A might inhibit the growth of S. suis by controlling the replication initiation and cell division through amino acid metabolism.
Project description:Brucella suis infects macrophages and dendritic cells. Wild boars act as reservoirs and carriers of Brucella suis biovar 2, and there is evidence that wild boar can be the main source of infection for domestic pigs through the venereal route. Transmission through this route could be an important path for disesease dissemination. The result from this study will contribute to the overall understanding of the molecular pathogenic mechanisms involved during Brucella suis infection in European wild boar.
Project description:Streptococcus suis serotype 2 is an important pathogen of pigs, and the disease it causes is characterized by meningitis, septicaemia and pneumonia with high mortality. The pathogen is also an emerging zoonotic agent and threatens humans that are exposed to pigs or their by-products. We investigated the response of PBMC (Peripheral Blood Mononuclear Cell), brain and lung tissues to infection with S. suis 2 strain SC19 by using the Affymetrix Porcine Genome Array. Six piglets free of S. suis 2 were allocated randomly to the infected group and the uninfected group. Each piglet of the infected group was intravenous injection with Streptococcus suis 2 strain SC19 at a dose of 3Ã105 colony-forming units (CFU). Each piglet of the noninfected group was treated similarly with an identical volume of PBS as control. At 24 h after challenge, the pigs were slaughtered and their brains, lungs and PBMC were collected with RNase-free equipment for microarray analysis.
Project description:Streptococcus suis is an important zoonotic pathogen that can cause meningitis and sepsis in both pigs and humans. In this study,we evaluated the genetic difference of 40 Streptococcus suis strains belonging to various sequence types by comparative genomic hybridization to identify genes associated with the variation in pathogenicity using NimbleGenM-bM-^@M-^Ys tilling microarray platform. Application of Comparative Phylogenomics to Identify Genetic Differences Relating to Pathogenicity of Streptococcus suis Comparative genomic analysis on the 40 S.suis strains of different serotypes and ST types through tilling arrays
Project description:Identification of Genes and Genomic Islands Correlated with High Pathogenicity through Tilling Microarray-Based Comparative Genomics in S. suis. Streptococcus suis is an important zoonotic pathogen that can cause meningitis and sepsis in both pigs and humans. S. suis isolates have been categorized into groups of different levels of pathogenicity, with sequence type (ST) ST1 clonal complex strains having a higher degree of virulence than other STs. However, the genetic basis of the differences in pathogenicity is still poorly understood. In this study, a comprehensive genomic comparison of 31 S. suis strains from different clinical sources with the genome sequence of the high pathogenicity (HP) strain GZ1 was conducted using NimbleGenM-bM-^@M-^Ys tilling microarray platform. Comparative genomic analysis on the 31 S. suis strains of different serotypes and ST types through tilling arrays.
Project description:Streptococcus suis is a major pig pathogen as well as an emerging zoonotic pathogen. Previous work has demonstrated that the S. suis extracellular amylopullulanase enzyme (ApuA) that degrades {alpha}-glucans also functions as an adhesin for porcine epithelial cells. To identify the mechanisms linking carbohydrate metabolism and virulence, we first compared the transcriptome of S. suis in minimal medium supplemented with glucose to minimal medium containing a complex carbohydrate pullulan as a carbon source. The relative expression of eighteen virulence genes including suilysin and apuA was increased during growth in presence of pullulan, compared to growth in glucose. Increased virulence potential of S. suis grown in pullulan was demonstrated using hemolytic assays and increased adhesion and invasion of porcine epithelial cells in vitro. A metabolic map of S. suis was generated and combined with transcriptome data to visualize the metabolic adaption of S. suis during adhesion and invasion of the porcine epithelial cells representing an in vitro model of infection. The role of carbon catabolite control in virulence gene regulation was investigated and the molecular mechanism of transcriptional regulation was elucidated for apuA. We demonstrate that relief of CcpA repression is a crucial transcriptional control mechanism linking carbohydrate mechanism and virulence. The model for the transcriptional regulation of two important virulence factors apuA and suilysin was verified by qPCR analysis of gene expression in S. suis recovered from the organs and blood of infected pigs.
Project description:Brucella suis infects macrophages and dendritic cells. Wild boars act as reservoirs and carriers of Brucella suis biovar 2, and there is evidence that wild boar can be the main source of infection for domestic pigs through the venereal route. Transmission through this route could be an important path for disesease dissemination. The result from this study will contribute to the overall understanding of the molecular pathogenic mechanisms involved during Brucella suis infection in European wild boar. Experiment Overall Design: In this study we preliminarily characterized differential gene expression in European wild boar naturally infected with Brucella suis biovar 2 using Microarray hybridization and Real Time RT-PCR analysis. Since Brucella suis acts by infecting macrophages, we used spleen cells to analyze the gene expression response to Brucella suis infection.