Campylobacter jejuni interactions with Acanthamoeba castellanii
Ontology highlight
ABSTRACT:
ORGANISM(S): Acanthamoeba castellanii Campylobacter jejuni
PROVIDER: GSE206909 | GEO | 2022/11/02
REPOSITORIES: GEO
Similar Datasets
Project description:Transcriptional regulation mediates adaptation of pathogens to environmental stimuli and is important for host colonisation. The Campylobacter jejuni genome sequence reveals a surprisingly small set of regulators, mostly of unknown function, suggesting an intricate regulatory network. Interestingly, C. jejuni lacks the homologues of ubiquitous regulators involved in stress response found in many other Gram-negative bacteria. Nonetheless, cj1000 is predicted to code for the sole LysR-type regulator in the C. jejuni genome, and thus may be involved in major adaptation pathways. A cj1000 mutant strain was constructed and found to be attenuated in its ability to colonise 1-day old chicks. Complementation of cj1000 mutation restored the colonisation ability to that of wild type levels. The mutant strain was also outcompeted in a competitive colonisation assay of the piglet intestine. High resolution oxygraphy was carried out for the first time on C. jejuni and revealed a role for Cj1000 in controlling O2 consumption. Furthermore, microarray analysis of the cj1000 mutant revealed both direct and indirect regulatory targets, including genes involved in energy metabolism and oxidative stress defences. These results highlight the importance of Cj1000 regulation in host colonisation and in major physiological pathways.
2013-07-03 | GSE43792 | GEO
Project description:Transcriptional regulation mediates adaptation of pathogens to environmental stimuli and is important for host colonisation. The Campylobacter jejuni genome sequence reveals a surprisingly small set of regulators, mostly of unknown function, suggesting an intricate regulatory network. Interestingly, C. jejuni lacks the homologues of ubiquitous regulators involved in stress response found in many other Gram-negative bacteria. Nonetheless, cj1000 is predicted to code for the sole LysR-type regulator in the C. jejuni genome, and thus may be involved in major adaptation pathways. A cj1000 mutant strain was constructed and found to be attenuated in its ability to colonise 1-day old chicks. Complementation of cj1000 mutation restored the colonisation ability to that of wild type levels. The mutant strain was also outcompeted in a competitive colonisation assay of the piglet intestine. High resolution oxygraphy was carried out for the first time on C. jejuni and revealed a role for Cj1000 in controlling O2 consumption. Furthermore, microarray analysis of the cj1000 mutant revealed both direct and indirect regulatory targets, including genes involved in energy metabolism and oxidative stress defences. These results highlight the importance of Cj1000 regulation in host colonisation and in major physiological pathways. Microarray data was collected from three independent biological replicates and 3-9 technical replicates for each biological replicate.
2013-07-03 | E-GEOD-43792 | biostudies-arrayexpress
Project description:Transcriptional profile of C. jejuni NCTC11168 while growing in MEM medium containing L-fucose. We hypothesize that certain C. jejuni strains, containing A certain genomic island, have acquired the ability to metabolize fucose. This study demonstrates the transcriptional profile C. jejuni growth while utilizing fucose.
2011-04-01 | GSE28294 | GEO
Project description:While growing in the human intestine, C. jejuni grows within the mucus layer. The largest constituents of this layer are the large mucin glycoproteins. A transcriptomic profile of C. jejuni NCTC11168 growing in a mucin-containing minimal medium seeks to describe the effect of the presence of mucin proteins on the transcriptome of C. jejuni.
2011-04-01 | GSE28295 | GEO
Project description:In order to cause disease, the food- and water-borne pathogen Campylobacter jejuni must face the extreme acidity of the host stomach as well as cope with pH fluctuations in the intestine. In the present study, C. jejuni NCTC 11168 was grown under mild acidic conditions mimicking those encountered in the intestine. The resulting transcriptional profiles revealed how this bacterium fine-tunes gene expression in response to acid stress. This adaptation involves differential expression of respiratory pathways, induction of genes for phosphate transport and repression of energy generation and intermediary metabolism genes. Keywords: acid shock; dose response; transcriptional response to 3 mild-acidic pH growth conditions (pH6.5, pH 6.0 and pH5.0)
2008-01-21 | GSE9920 | GEO
Project description:Growth of Campylobacter jejuni in butyrate, including deletions of a TCS involved in sensing this response
2021-01-01 | GSE142852 | GEO
Project description:Campylobacter jejuni causes food- and water-borne gastroenteritis, and as such must survive passage through the stomach in order to reach the gastrointestinal tract. While little is known about how C. jejuni survives transit through the stomach, its low infectious dose suggests it is well equipped to sense and respond to acid shock. In this study, the transcriptional profile of C. jejuni NCTC 11168 was obtained after exposure to in in vivo (piglet stomach) acid shock. Keywords: acid shock; in vivo study; transit through the host stomach
2008-01-21 | GSE9938 | GEO
Project description:During colonization in the host gastrointestinal tract, the enteric bacteria Campylobacter jejuni is exposed to a variety of signaling molecules including the catecholamine hormones epinephrine (Epi) and norepinephrine (NE). NE has been determined to stimulate the growth of C. jejuni as well as increase its pathogenicity. To investigate the mechanisms of NE or Epi on the biology of C. jejuni, the global gene expression profiles of C. jejuni NCTC 11168 cultured in iron-restricted medium were analyzed in response to NE or Epi. Totally, 183 and 156 genes were differentially expressed by NE and Epi respectively, with 102 differentially expressed genes common between the two treatments. These genes are involved in diverse cellular functions including iron uptake systems, motility, virulence, oxidative stress response, nitrosative stress tolerance, enzyme metabolism, DNA repair and metabolism and ribosomal protein biosynthesis. Adherence to and invasion of Caco-2 cells by C. jejuni were enhanced upon exposure to NE or Epi. These results indicated that NE and Epi have similar effects on the gene expression of C. jejuni and that the effects on gene expression may contribute to elucidate the mechanisms on interaction between host and C. jejuni.
2015-02-10 | GSE65187 | GEO
Project description:Campylobacter jejuni is the prevalent cause of bacterial gastroenteritis in human worldwide. The ability to survive stomach acidity is a fundamental requirement for C. jejuni to colonize the host and cause disease. However, the mechanism of C. jejuni acid survival is still unknown. Herein, we demonstrated that C. jejuni is able to survive acidic conditions at pH 4 up to 8 min without a drop in viability. The acid stimulon of C. jejuni 81-176 revealed the up-regulation of many genes important for Campylobacter acid survival such as heat shock genes and genes involved in energy metabolism. On the other hand, the repression of ribosomal genes highlights the ability of C. jejuni to direct its machinery to survive stressful conditions. Prior acid exposure cross-protected C. jejuni against oxidative stress suggesting an overlap in C. jejuni’s responses to various stresses. Interestingly, the induced expression of virulence genes in C. jejuni upon acid exposure such as the Campylobacter invasion antigen (ciaB) indicates that acid stress plays a role in C. jejuni host pathogenesis. Acid exposure significantly enhanced C. jejuni pathogenesis in both eukaryotic cells and G. melonella. To the best of our knowledge, this is the first study characterizes the influence of acid stress on C. jejuni pathogenesis in an infection model. Altogether, this study uncovers the transcriptional profile of C. jejuni in response to acidic conditions as those encountered in the stomach. In addition, our results demonstrate that acid stress jump-starts C. jejuni for efficient gut colonization and host pathogenesis. Campylobacter jejuni is the prevalent cause of bacterial gastroenteritis in human worldwide. The ability to survive stomach acidity is a fundamental requirement for C. jejuni to colonize the host and cause disease. However, the mechanism of C. jejuni acid survival is still unknown. Herein, we demonstrated that C. jejuni is able to survive acidic conditions at pH 4 up to 8 min without a drop in viability. The acid stimulon of C. jejuni 81-176 revealed the up-regulation of many genes important for Campylobacter acid survival such as heat shock genes and genes involved in energy metabolism. On the other hand, the repression of ribosomal genes highlights the ability of C. jejuni to direct its machinery to survive stressful conditions. Prior acid exposure cross-protected C. jejuni against oxidative stress suggesting an overlap in C. jejuni’s responses to various stresses. Interestingly, the induced expression of virulence genes in C. jejuni upon acid exposure such as the Campylobacter invasion antigen (ciaB) indicates that acid stress plays a role in C. jejuni host pathogenesis. Acid exposure significantly enhanced C. jejuni pathogenesis in both eukaryotic cells and G. melonella. To the best of our knowledge, this is the first study characterizes the influence of acid stress on C. jejuni pathogenesis in an infection model. Altogether, this study uncovers the transcriptional profile of C. jejuni in response to acidic conditions as those encountered in the stomach. In addition, our results demonstrate that acid stress jump-starts C. jejuni for efficient gut colonization and host pathogenesis.
2016-10-01 | GSE73793 | GEO
Project description:Major foodborne bacterial pathogens, such as Campylobacter jejuni, have devised complex strategies to establish and foster intestinal infections. For more than two decades researchers have used immortalized cell lines derived from human intestinal tissue to dissect C. jejuni-host cell interactions. Known from these studies is that C. jejuni virulence is multifactorial, requiring a coordinated response to produce virulence factors that facilitate the bacterium’s host-cell interactions. This study was initiated to identify C. jejuni proteins that contribute to adaptation to the host cell environment and cellular invasion. We demonstrated that C. jejuni responds to INT 407 and Caco-2 cells in a similar fashion at the cellular and molecular levels. Active protein synthesis was found to be required for C. jejuni to maximally invade these host cells. Proteomic and transcriptomic approaches were then used to define the protein and gene expression profiles of C. jejuni co-cultured with cells. By focusing on those genes showing increased expression by C. jejuni when co-cultured with epithelial cells, we discovered that C. jejuni quickly adapts to co-culture with epithelial cells by synthesizing gene products that enable it to acquire specific amino acids for growth, scavenge for inorganic molecules including iron, resist reactive oxygen/nitrogen species, and promote bacteria-host cell interactions. Based on these findings, we selected a subset of the genes involved in chemotaxis and the regulation of flagellar assembly and generated C. jejuni deletion mutants for phenotypic analysis. Binding and internalization assays revealed significant differences in the interaction of C. jejuni chemotaxis and flagellar regulatory mutants. The identification of genes involved in C. jejuni adaptation to culture with host cells provides new insights into the infection process.
2019-04-11 | GSE114909 | GEO