Project description:Erythromycin is the drug of choice to treat campylobacteriosis, but resistance to this antibiotic is rising. The adaptive mechanisms employed by Campylobacter jejuni to erythromycin treatment remain unknown. The aim of this study is to determine the molecular basis underlying Campylobacter’s immediate response to Ery treatment.
Project description:Erythromycin is the drug of choice to treat campylobacteriosis, but resistance to this antibiotic is rising. The adaptive mechanisms employed by Campylobacter jejuni to erythromycin treatment remain unknown. The aim of this study is to determine the molecular basis underlying CampylobacterM-bM-^@M-^Ys immediate response to Ery treatment. The design utilized an available two color microarray slide for the entire transcriptome of Campylobacter jejuni macrolide resistant strain JL272. One hybridizations were performed: sham-treated JL272 v.s. lethal dose erythromycin treated JL272. Samples were independently grown and harvested. There were three biological replicates of each sample.
Project description:Erythromycin is the drug of choice to treat campylobacteriosis, but resistance to this antibiotic is rising. The adaptive mechanisms employed by Campylobacter jejuni to erythromycin treatment remain unknown. The aim of this study is to determine the molecular basis underlying Campylobacter’s immediate response to Ery treatment.
Project description:Erythromycin is the drug of choice to treat campylobacteriosis, but resistance to this antibiotic is rising. The adaptive mechanisms employed by Campylobacter jejuni to erythromycin treatment remain unknown. The aim of this study is to determine the molecular basis underlying Campylobacter’s immediate response to Ery treatment.
Project description:Cj0440c, a putative transcriptional regulator, was over-expressed in the high-level erythromycin-resistant (Eryr) Campylobacter jejuni strains. To determine the role of Cj0440c on the development and fitness of erythromycin resistance in C. jejuni, we knocked out Cj0440c in Eryr strain (R) to obtain the Cj0440c mutants (RM). Then we compared the transcriptome of the Cj0440c mutant with that of the parent strain using DNA microarray. These comparisons identified 9 genes that showed a ≥2-fold change in expression in RM. The differentially expressed genes in RM are related to flagellar biosynthesis and unknown functions. What's more, katA, encoding catalase, down-regulated in RM. Cj0440c may progress flagellar genes expression, help to escape drug pressure and disseminate and colonize smoothly, and Cj0440c in Eryr Campylobacter may protect bacteria from harmful oxygen stress from the host immune system, other microorganism in host intestinal and its own products. These findings indicate that Cj0440c is essential for the fitness (growth) of resistant C. jejuni by controlling the expression of several genes involved in flagellar assembly and catalase, enhancing cell motility for colonization and invasion under the pressure of drug. This study widened our understanding on the molecular mechanism of resistance and provides scientific reference for drug research and application.
Project description:Cj0440c, a putative transcriptional regulator, was over-expressed in the high-level erythromycin-resistant (Eryr) Campylobacter jejuni strains. To determine the role of Cj0440c on the development and fitness of erythromycin resistance in C. jejuni, we knocked out Cj0440c in Eryr strain (R) to obtain the Cj0440c mutants (RM). Then we compared the transcriptome of the Cj0440c mutant with that of the parent strain using DNA microarray. These comparisons identified 9 genes that showed a M-bM-^IM-%2-fold change in expression in RM. The differentially expressed genes in RM are related to flagellar biosynthesis and unknown functions. What's more, katA, encoding catalase, down-regulated in RM. Cj0440c may progress flagellar genes expression, help to escape drug pressure and disseminate and colonize smoothly, and Cj0440c in Eryr Campylobacter may protect bacteria from harmful oxygen stress from the host immune system, other microorganism in host intestinal and its own products. These findings indicate that Cj0440c is essential for the fitness (growth) of resistant C. jejuni by controlling the expression of several genes involved in flagellar assembly and catalase, enhancing cell motility for colonization and invasion under the pressure of drug. This study widened our understanding on the molecular mechanism of resistance and provides scientific reference for drug research and application. An eight-chip study using total RNA recoverd from four separate resistant-type cultures of Erythrocin-resistant Campylobacter jejuni NCTC 111168 (R) and four separate cultures of a mutant strain, erythrocin-resistant Campylobacter jejuni NCTC 11168 delta- Cj0440c (RM), in which Cj0440c is deleted. Each chip measures the expression level of 1634 genes from Campylobacter jejuni NCTC 11168.
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:Erythromycin is the drug of choice to treat campylobacteriosis, but resistance to this antibiotic is rising. The adaptive mechanisms employed by Campylobacter jejuni to erythromycin treatment remain unknown. The aim of this study is to determine the molecular basis underlying CampylobacterM-bM-^@M-^Ys immediate response to Ery treatment. The design utilized an available two color microarray slide for the entire transcriptome of Campylobacter jejuni wild type strain NCTC 11168. One hybridizations were performed: sham-treated NCTC 11168 v.s. lethal dose erythromycin treated NCTC 11168. Samples were independently grown and harvested. There were three biological replicates of each sample.
Project description:Erythromycin is the drug of choice to treat campylobacteriosis, but resistance to this antibiotic is rising. The adaptive mechanisms employed by Campylobacter jejuni to erythromycin treatment remain unknown. The aim of this study is to determine the molecular basis underlying CampylobacterM-bM-^@M-^Ys immediate response to Ery treatment. The design utilized an available two color microarray slide for the entire transcriptome of Campylobacter jejuni wild type strain NCTC 11168. One hybridizations were performed: sham-treated NCTC 11168 v.s. sub-lethal dose erythromycin treated NCTC 11168. Samples were independently grown and harvested. There were three 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. 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.