Project description:Campylobacter, a major foodborne pathogen, is increasingly resistant to macrolide antibibotics. previous findings suggeted that development of macrolide resistance in campylobacter requires a multi-step process, but the molecular mechanisms involved in the process are not known. In our study, multiple seriess of macrolide-resistant C. jejuni mutants were selected in vitro by stepwise exposure of C. jejuni 81-176 to increasing concentrations of erythromycin and tylosin. A set of the selected resistance were subjected to microarray and the the global transcriptional profile was analyzed. In this sery, DNA microarray was used to compare the gene expression profiles of macrolide resistant strains (76E2, 76E8 and 76E64) with its parent wild-type strain C. jejuni 81-176. This assay identified a large number of genes that showed >1.5 fold changes (q-value<0.1) in expression in the macrolide resistant strains. The up-regulated genes are involved in surface structure,ribosomal, heat shock and some specific Misc memerbrane , while the majority of the down-regulated genes are involved in energy metabolism, amino acid biosynthesis. The over-expression of genes involved in surface structure and Misc memerbrance was associated with the development of intermedial-level resistance to macrolide in campylobacter 81-176. Keywords:intermedial-level macrolide resistant C. jejuni selected from C. jejuni 81-176. step-wise selection.
Project description:Campylobacter, a major foodborne pathogen, is increasingly resistant to macrolide antibibotics. previous findings suggeted that development of macrolide resistance in campylobacter requires a multi-step process, but the molecular mechanisms involved in the process are not known. In our study, multiple seriess of macrolide-resistant C. jejuni mutants were selected in vitro by stepwise exposure of C. jejuni 81-176 to increasing concentrations of erythromycin and tylosin. A set of the selected resistance were subjected to microarray and the the global transcriptional profile was analyzed. In this sery, DNA microarray was used to compare the gene expression profiles of macrolide resistant strains (76E2, 76E8 and 76E64) with its parent wild-type strain C. jejuni 81-176. This assay identified a large number of genes that showed >1.5 fold changes (q-value<0.1) in expression in the macrolide resistant strains. The up-regulated genes are involved in surface structure,ribosomal, heat shock and some specific Misc memerbrane , while the majority of the down-regulated genes are involved in energy metabolism, amino acid biosynthesis. The over-expression of genes involved in surface structure and Misc memerbrance was associated with the development of intermedial-level resistance to macrolide in campylobacter 81-176. Keywords:intermedial-level macrolide resistant C. jejuni selected from C. jejuni 81-176. step-wise selection. The design utilized an available two color microarray slide for the entire transcriptome of Campylobacter jejuni. Four hybridizations were performed each with independently extracted samples of either macrolide susceptible C. jejuni 81-176 cDNA samples or macrolide resistant C. jejuni cDNA samples. A dye swap was utilized to help minimize dye dependent bias. Thus there were three to four biological replicates of each sample.
Project description:Campylobacter, a major foodborne pathogen, is increasingly resistant to macrolide antibibotics. Previous findings suggested that development of macrolide resistance in Campylobacter requires a multi-step process, but the molecular mechanisms involved in the process are not known. In our study, erythromycin-resistant C. jejuni mutant (R) was selected in vitro by stepwise exposure of C. jejuni NCTC11168(S) to increasing concentrations of erythromycin.The resistant were subjected to microarray and the the global transcriptional profile was analyzed. In this series, DNA microarray was used to compare the gene expression profiles of the macrolide-resistant strain with its parent wild-type strain NCTC11168. A large number of gene showed significant changes in R. The up-regulated genes in the resistant strains are involved in miscellaneous periplasmic proteins, efflux protein and putative aminotransferase, while the majority of the down-regulated genes are involved in electron transport, lipoprotein, heat shock protein and unknown function proteins. The over-expression of efflux pump and periplasmic protein was involved in the development of resistance to macrolide in C. jejuni.
Project description:Campylobacter, a major foodborne pathogen, is increasingly resistant to macrolide antibibotics. Previous findings suggested that development of macrolide resistance in Campylobacter requires a multi-step process, but the molecular mechanisms involved in the process are not known. In our study, erythromycin-resistant C. jejuni mutant (R) was selected in vitro by stepwise exposure of C. jejuni NCTC11168(S) to increasing concentrations of erythromycin.The resistant were subjected to microarray and the the global transcriptional profile was analyzed. In this series, DNA microarray was used to compare the gene expression profiles of the macrolide-resistant strain with its parent wild-type strain NCTC11168. A large number of gene showed significant changes in R. The up-regulated genes in the resistant strains are involved in miscellaneous periplasmic proteins, efflux protein and putative aminotransferase, while the majority of the down-regulated genes are involved in electron transport, lipoprotein, heat shock protein and unknown function proteins. The over-expression of efflux pump and periplasmic protein was involved in the development of resistance to macrolide in C. jejuni. An eight chip study using total RNA recovered from four separate resistant-type cultures of Erythrocin-resistant Campylobacter jejuni NCTC111168 (R) and four separate cultures of Campylobacter jejuni NCTC111168 (S). Each chip measures the expression level of 1634 genes from Campylobacter jejuni NCTC11168.
Project description:Campylobacter, a major foodborne pathogen, is increasingly resistant to macrolide antibibotics. Previous findings suggeted that development of macrolide resistance in campylobacter requires a multi-step process, but the molecular mechanisms involved in the process are not known. In our study, multiple series of macrolide-resistant C. jejuni mutants were selected in vitro by stepwise exposure of C. jejuni NCTC11168 to increasing concentrations of erythromycin and tylosin. A set of the selected resistance were subjected to microarray and the the global transcriptional profile was analyzed. In this sery, DNA microarray was used to compare the gene expression profiles of macrolide resistant strains (68E1, 68E8 and 68E64) with its parent wild-type strain NCTC11168. The assay identified a small number of genes that showed significant changes (q-value<0.1) in expression in the low-level macrolide resistant strain 68E1, while a large number of gene showing significant changes in intermedia-level resistant stran 68E8 and high-level resistant strain 68 E64. The up-regulated genes in the resistant strains are involved in miscellaneous periplasmic proteins, efflux protienand putative aminotransferase, while the majority of the down-regulated genes are involved in electron transport,lipoprotein, heat shock protein and unknown function proteins. These findings suggest that there is not much change in low-level macrolide resistant C. jejuni strain. The over-expression of efflux pump and periplasmic protein was involved in the development of resistance to macrolide in C. jejuni. Keywords: macrolide resistant C. jejuni selected from NCTC 11168 step-wise selection.
Project description:This study investigates the CsrA regulon of the food-borne pathogen Campylobacter jejuni. Direct RNA binding targets of CsrA in two strains of C. jejuni, NCTC11168 and 81-176, were determined using RIP-seq.
Project description:Campylobacter, a major foodborne pathogen, is increasingly resistant to macrolide antibibotics. Previous findings suggeted that development of macrolide resistance in campylobacter requires a multi-step process, but the molecular mechanisms involved in the process are not known. In our study, multiple series of macrolide-resistant C. jejuni mutants were selected in vitro by stepwise exposure of C. jejuni NCTC11168 to increasing concentrations of erythromycin and tylosin. A set of the selected resistance were subjected to microarray and the the global transcriptional profile was analyzed. In this sery, DNA microarray was used to compare the gene expression profiles of macrolide resistant strains (68E1, 68E8 and 68E64) with its parent wild-type strain NCTC11168. The assay identified a small number of genes that showed significant changes (q-value<0.1) in expression in the low-level macrolide resistant strain 68E1, while a large number of gene showing significant changes in intermedia-level resistant stran 68E8 and high-level resistant strain 68 E64. The up-regulated genes in the resistant strains are involved in miscellaneous periplasmic proteins, efflux protienand putative aminotransferase, while the majority of the down-regulated genes are involved in electron transport,lipoprotein, heat shock protein and unknown function proteins. These findings suggest that there is not much change in low-level macrolide resistant C. jejuni strain. The over-expression of efflux pump and periplasmic protein was involved in the development of resistance to macrolide in C. jejuni. Keywords: macrolide resistant C. jejuni selected from NCTC 11168 step-wise selection. The design utilized an available two color microarray slide for the entire transcriptome of Campylobacter jejuni. Four hybridizations were performed each with independently extracted samples of either macrolide susceptible C. jejuni NCTC11168 cDNA samples or macrolide resistant C.jejuni cDNA samples. A dye swap was utilized to help minimize dye dependent bias. Thus, there were four biological replicates of each sample.
Project description:Campylobacter jejuni is the leading cause of campylobacteriosis in the developed world. Although most cases are caused by consumption of contaminated meat, a significant proportion is caused by consumption of contaminated water. Some C. jejuni isolates are better than others at surviving in water, which suggests that these strains are better adapted to transmission by water than others. The aim of this study is to investigate this phenomenon further. CFU counts and viability assays showed that strain 81116 survives better than strain 81-176 in a defined freshwater medium at 4°C. Comparative transcriptomic profiling using microarray revealed that these strains respond differently to water. This series presents the transcriptome of strain 81-176 in water.
Project description:This study investigates the CsrA regulon of the food-borne pathogen Campylobacter jejuni. Direct RNA binding targets of CsrA in two strains of C. jejuni, NCTC11168 and 81-176, were determined using RIP-seq. Identification of CsrA binding sites in two C. jejuni strains using RIP-seq