Project description:Streptococcus suis 2 Rgg-dependent transcription was analyzed. Microarray analysis was performed using RNA samples isolated from Streptococcus suis 2 wild-type strain 05ZYH33 as well as RNA isolated from 05ZYH33 rgg isogenic mutant strain during postexponential phases of growth.
Project description:For a pathogen such as Streptococcus suis serotype 2, ecological success is determined by its ability to sense the environment and mount an appropriate adaptive transcriptional response. Thus, determining conditions for analysis of gene expression in vitro that are representative of the in vivo environment is critical for understanding the contributions of transcriptional response pathways to pathogenesis. In this study, we used analysis of the global expression profile in response to acidic pH in vitro and identified a set of regulated genes involved in diverse cellular processes. 196 (11%) genes were differentially regulated by the acid stress: 92 (47%) were down-regulated at low acid (pH 5.8) relative to the neutral condition (pH 7.2), whereas 104 (53%) were up-regulated at pH 5.8 versus pH 7.2. To confirm the microarray data, 16 genes were measured by quantitative RT-PCR. There was a strong positive correlation (r = 0.96) between the results obtained by microarray and quantitative RT-PCR. The data showed that S. suis S2 is equally capable of inducing an acid tolerance response with maximal protection provided after adaptation at pH 5.8 for survival.
Project description:For a pathogen such as Streptococcus suis serotype 2, ecological success is determined by its ability to sense the environment and mount an appropriate adaptive transcriptional response. Thus, determining conditions for analysis of gene expression in vitro that are representative of the in vivo environment is critical for understanding the contributions of transcriptional response pathways to pathogenesis. In this study, we used analysis of the global expression profile in response to acidic pH in vitro and identified a set of regulated genes involved in diverse cellular processes. 196 (11%) genes were differentially regulated by the acid stress: 92 (47%) were down-regulated at low acid (pH 5.8) relative to the neutral condition (pH 7.2), whereas 104 (53%) were up-regulated at pH 5.8 versus pH 7.2. To confirm the microarray data, 16 genes were measured by quantitative RT-PCR. There was a strong positive correlation (r = 0.96) between the results obtained by microarray and quantitative RT-PCR. The data showed that S. suis S2 is equally capable of inducing an acid tolerance response with maximal protection provided after adaptation at pH 5.8 for survival. A cDNA microarray imprinted with 2156 genes representing about 98% of the Streptococcus suis serotype 2 genome was used for transcriptome analysis. For two-sample (reference vs. test) microarray hybridization, four independent bacterial cultures from each condition (pH 5.8, pH 7.2) were prepared as biological replicates for RNA isolation. Accordingly, four dual-fluorescence-labeled cDNA probes were prepared to hybridize with four slides. Pairwise comparisons were made using dye-swaps to avoid labeling bias. A ratio of mRNA levels (test/reference) was calculated for each gene. Significant changes of gene expression were identified with the SAM software. After the SAM analysis, only genes with at least 2-fold changes in expression were collected for further 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 NimbleGen’s tilling microarray platform. Application of Comparative Phylogenomics to Identify Genetic Differences Relating to Pathogenicity of Streptococcus suis
Project description:MetQ gene of Streptococcus suis serotype 2 deletion strain has attenuated antiphagocytosis. However,the mechanism of antiphagocytosis and pathogenesis of MetQ in SS2 has remained unclear. In this study, stable isotope labeling by amino acids in cell culture (SILAC) based liquid chromatography-mass spectrometry (LC-MS) and subsequent bioinformatics analysis was used to determine differentially expressed proteins of RAW264.7 cells infected with △MetQ and ZY05719, aimed at elucidating the mechanism of antiphagocytosis and innate immunity of macrophages infected by 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.
