Project description:Avian Pathogenic Escherichia coli (APEC) are a group of extra-intestinal E. coli that infect poultry, and are able to cause a variety of diseases, systemic or localized, collectively designated as colibacillosis. Colibacillosis is the most common bacterial illness in poultry production, resulting in significant economic losses world-wide. Despite of its importance, pathogenicity mechanisms of APEC strains remain not completelly elucidated and available vaccines are not fully effectives. In order to better understand which genes could be related to pathogenicity in different APEC isolated, a microarray analyses of two APEC strains representing: Swollen Head Syndrome and Omphalitis was carried out. We used the microarray methodology to evaluate the expression profile of two different APEC strains
Project description:Colisepticemia caused by avian pathogenic Escherichia coli (APEC) results in annual multimillion dollar losses to the poultry industry. Recent research suggests that APEC may have an important role in public health as well. Generally, colisepticemia follows a respiratory tract infection in which APEC penetrate the respiratory epithelium to enter the bloodstream. From the bloodstream, bacteria may spread to various internal organs resulting in perihepatitis, pericarditis, and other conditions. The aim of this study was to identify molecular mechanisms enabling APEC to survive and grow in the bloodstream. To do so, we compared the transcriptome of APEC O1 during growth in Luria-Bertani broth and chicken serum. Selected genes that were significantly up-regulated in chicken serum were then subjected to mutational analysis to confirm their role in APEC pathogenesis. Several categories of genes, predicted to contribute to adaptation and growth in the avian host, were identified. These included several known virulence genes and genes involved in adaptive metabolism, protein transport, biosynthesis pathways, stress resistance, and virulence regulation. Several genes with unknown function, which were localized to pathogenicity islands or APEC O1’s large virulence plasmid, were also identified, suggesting that they too contribute to survival in chicken serum. This genome-wide analysis provides novel insight into processes that are essential to APEC O1’s survival and growth in chicken serum. Two-condition experiment: LB vs. chicken serm; four biological replicates, independently grown and harvested.
Project description:Avian Pathogenic Escherichia coli (APEC) are a group of extra-intestinal E. coli that infect poultry, and are able to cause a variety of diseases, systemic or localized, collectively designated as colibacillosis. Colibacillosis is the most common bacterial illness in poultry production, resulting in significant economic losses world-wide. Despite of its importance, pathogenicity mechanisms of APEC strains remain not completelly elucidated and available vaccines are not fully effectives. In order to better understand which genes could be related to pathogenicity in different APEC isolated, a microarray analyses of two APEC strains representing: Swollen Head Syndrome and Omphalitis was carried out.
Project description:Colisepticemia caused by avian pathogenic Escherichia coli (APEC) results in annual multimillion dollar losses to the poultry industry. Recent research suggests that APEC may have an important role in public health as well. Generally, colisepticemia follows a respiratory tract infection in which APEC penetrate the respiratory epithelium to enter the bloodstream. From the bloodstream, bacteria may spread to various internal organs resulting in perihepatitis, pericarditis, and other conditions. The aim of this study was to identify molecular mechanisms enabling APEC to survive and grow in the bloodstream. To do so, we compared the transcriptome of APEC O1 during growth in Luria-Bertani broth and chicken serum. Selected genes that were significantly up-regulated in chicken serum were then subjected to mutational analysis to confirm their role in APEC pathogenesis. Several categories of genes, predicted to contribute to adaptation and growth in the avian host, were identified. These included several known virulence genes and genes involved in adaptive metabolism, protein transport, biosynthesis pathways, stress resistance, and virulence regulation. Several genes with unknown function, which were localized to pathogenicity islands or APEC O1’s large virulence plasmid, were also identified, suggesting that they too contribute to survival in chicken serum. This genome-wide analysis provides novel insight into processes that are essential to APEC O1’s survival and growth in chicken serum.
2011-04-01 | GSE25478 | GEO
Project description:Antimicrobial Susceptibility Prediction and Core Genome Multilocus Sequence Typing (cgMLST) of Acinetobacter baumannii
| PRJNA809687 | ENA
Project description:Antimicrobial Susceptibility Prediction and Core Genome Multilocus Sequence Typing (cgMLST) of Pseudomonas aeruginosa
Project description:Avian pathogenic Escherichia coli (APEC) is considered one of the most common infectious bacterial diseases resulting in significant economic losses in poultry industry worldwide. In order to investigate the association between host immune resistance and miRNA expression in the pathogenic process induced by APEC, miRNA expression profiles in broilers spleen were performed by Solexa deep sequencing from three different treatment groups including non-challenged (NC), challenged-mild pathology (MD), and challenged-severe pathology (SV).In total, 3 462 706, 3 586 689, and 3 591 027 clean reads were obtained for NC, MD, and SV, respectively. After comparing the miRNA expression patterns, 27 differentially expressed miRNAs were identified among the three response groups, which included 13 miRNAs between NC and MD, 17 between NC and SV, and 14 between MD and SV. For these miRNAs, different expression in MD and SV suggested they may have resistance activity in APEC infection. Through integrated analysis of miRNA and mRNA expression patterns, 43 negative pairs between miRNA and mRNA (r < -0.80) were obtained. 4 miRNAs were validated to be significant negatively correlated to targets by quantitative real time PCR: gga-miR-21 (CLEC3B and GGTLA1), gga-miR-429 (TMEFF2, CDC20, SHISA2 and NOX4), gga-miR-146b (LAT2 and WNK1), and gga-miR-215 (C7 and ASL2). Additionally, the expression of gga-miR-21 and gga-miR-146b was significantly up-regulated by LPS induced in HD11 macrophage cell. In contrast, gga-miR-429 has no significant change. In summary, we present the first report that characterized the miRNA profiles of chicken spleen in response to APEC infection, and identified several candidate miRNAs which might accelerate host immune response through down-regulating their specific target genes. Through the intra-air sac route into the left thoracic air sac, 240 non-vaccinated males at 4 weeks of age were challenged with 0.1 ml APEC O1 (10^8 colony forming units) and another 120 non-vaccinated males were non-challenged but treated with 0.1 ml PBS. Detailed information on the APEC O1 strain and challenge process was described by previously described study. Necropsy was performed at 1 day post challenge, and a summarized lesion ranging from 0 to 7 was determined for each APEC-challenged bird. Birds with lesions scoring 0-2 were regarded as mild infection, and those scoring 4-7 were designated as severe infection. The mild and severe pathology meant that birds were resistant and susceptible to APEC infection, respectively. Then, spleens from three groups, consisting of non-challenged, challenged-mild pathology and challenged-severe pathology were subjected to Solexa deep sequencing to investigate the dynamics of chicken miRNA expression.
Project description:Neisseria meningitidis is a major cause of bacterial meningitis and septicemia worldwide. Seven new serogroup C meningococci were isolated from two provinces of China in January, 2006. Their PorA VR types were P1.20, 9. Multilocus sequence typing results indicated that they all belonged to ST-7. It is a new serogroup C N. meningitidis sequence type clone identified in China. Here we also present the results of a genomic comparison of these isolates with other 15 N. meningitidis serogroup A and B isolates, which belonged to ST-7, based on comparative genomic hybridization analysis. The data described here would be helpful to monitor the spread of this new serogroup C meningococci sequence type clone in China and worldwide. Keywords: comparative genomic hybridization
2007-10-11 | GSE7331 | GEO
Project description:Development and Evaluating a core genome multilocus sequence typing (cgMLST) scheme for whole-genome sequence-based typing of Clostridioides difficile
Project description:APEC most often infect chickens, turkeys, ducks, and other avian species, and therefore pose a significant economic burden on the poultry industry worldwide. Few studies have analyzed the genome-wide transcriptional profile of APEC during infection in vivo. In this study, we examined the genome-wide transcriptional response of APEC O2 strain E058 in an in vivo chicken infection model to better understand the factors necessary for APEC colonization, growth, and survival in vivo. An Affymetrix multigenome DNA microarray, which contains most of the genomic open reading frames of E. coli K-12 strain MG1655, uropathogenic E. coli strain CFT073, and E. coli O157:H7 strain EDL 933, was used to profile the gene expression in APEC E058.The genes highly expressed during infection were involved in metabolism, iron acquisition or transport, virulence, response to stress, and biological regulation. Many genes encoding putative or hypothetical proteins were also strongly upregulated, implying that some undiscovered mechanism may underlie APEC pathogenesis.