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Expression data of Actinobacillus pleuropneumoniae 4074 in response to epinephrine and norepinephrine

ABSTRACT: Bacteria can use host hormones as environment cue to modulate their pathogenic processes, which was discovered to play essential role in disease development. Actinobacillus pleuropneumoniae is one of the most important porcine respiratory pathogens causing great economic losses in the pig industry worldwide. Stress factors were found to contribute to the outcome of A. pleuropneumoniae infection. To test whether A. pleuropneumoniae could respond to host stress hormone catecholamines, the gene expression profiles after epinephrine (Epi) and norepinephrine (NE) treatment were compared with the untreated bacteria using microarray. Although the bacterial growth was not affected in the conditions tested, 157 and 104 genes associated with various function categories including many virulence factors were differentially expressed by Epi and NE treatment. 18 common genes were regulated by the two hormones, these genes included genes encoding virulence factors and potential responsors of Epi and NE. Further investigations on virulence traits demonstrated that cytotoxic activity was enhanced by Epi but repressed by NE in accordance with the regulations on apxIA. Biofilm formation was not affected by the two hormones despite that the biofilm formation gene pgaB was affected. Adhesion to host cells was induced by NE but not by Epi, possibly involving other putative adhesins affected by the hormones in addition to the autotransporter adhesin (APL_0443). Our study demonstrated that A. pleuropneumoniae could actively respond to catecholamines to control its virulence traits. The different regulated genes and effects caused by Epi and NE suggested A. pleuropneumoniae may have multiple responsive systems to sense different type of catecholamine hormones.

ORGANISM(S): Actinobacillus pleuropneumoniae Actinobacillus pleuropneumoniae serovar 1 str. 4074

PROVIDER: GSE25516 | GEO | 2012/03/19

SECONDARY ACCESSION(S): PRJNA133769

REPOSITORIES: GEO

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Project description:Bacteria can use host hormones as environment cue to modulate their pathogenic processes, which was discovered to play essential role in disease development. Actinobacillus pleuropneumoniae is one of the most important porcine respiratory pathogens causing great economic losses in the pig industry worldwide. Stress factors were found to contribute to the outcome of A. pleuropneumoniae infection. To test whether A. pleuropneumoniae could respond to host stress hormone catecholamines, the gene expression profiles after epinephrine (Epi) and norepinephrine (NE) treatment were compared with the untreated bacteria using microarray. Although the bacterial growth was not affected in the conditions tested, 157 and 104 genes associated with various function categories including many virulence factors were differentially expressed by Epi and NE treatment. 18 common genes were regulated by the two hormones, these genes included genes encoding virulence factors and potential responsors of Epi and NE. Further investigations on virulence traits demonstrated that cytotoxic activity was enhanced by Epi but repressed by NE in accordance with the regulations on apxIA. Biofilm formation was not affected by the two hormones despite that the biofilm formation gene pgaB was affected. Adhesion to host cells was induced by NE but not by Epi, possibly involving other putative adhesins affected by the hormones in addition to the autotransporter adhesin (APL_0443). Our study demonstrated that A. pleuropneumoniae could actively respond to catecholamines to control its virulence traits. The different regulated genes and effects caused by Epi and NE suggested A. pleuropneumoniae may have multiple responsive systems to sense different type of catecholamine hormones. Transcriptional profiles were analyzed using microarray to compared the epinephrine (Epi) or norepinephrine(NE) treated and untreated A. pleuropneumoniae. All samples were harvested from middle exponential phase (4 hours after sub-culture) at the OD600=1.435M-BM-10.065 for control, OD600=1.461M-BM-10.019 for Epi treated strain and OD600=1.545M-BM-10.115 for NE treated strain. Three biological replicates were conducted for each treatment. The total RNA were extracted and hybridized with the whole genome microarray of A. pleuropneumoniae. The signal intensities were normalized and transformed into log2 values. The genes with fold change M-bM-^IM-% 1.5 and P < 0.05 were selected as differentially expressed.

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. Transcriptional profiles were analyzed using microarray to compared the epinephrine (Epi) or norepinephrine (NE) treated and untreated Campylobacter jejuni NCTC 11168. NE or Epi treated and untreated cultures of C. jejuni NCTC 11168 were collected at the mid-log phase (?36 h cultures). Three (for NE or Epi treated culture) or four (for untreated control culture) independent biological replicates were performed. Total RNA was extracted using RiboPure™-Bacteria Kit (Ambion, Life Technologies) according to the manufacturer’s instructions. The quality and quantity of total RNA were determined by an Agilent Bioanalyzer 2100. Total RNA was amplified and labeled by Low Input Quick Amp Labeling Kit, One-Color, following the manufacturer’s instructions. Labeled cRNA were purified by RNeasy mini kit (QIAGEN, GmBH, Germany). Each Slide was hybridized with 600ng Cy3-labeled cRNA using Gene Expression Hybridization Kit (Agilent technologies, Santa Clara, CA, US) in Hybridization Oven, according to the manufacturer’s instructions. After 17 hours hybridization, slides were washed in staining dishes with Gene Expression Wash Buffer Kit (Agilent technologies, Santa Clara, CA, US), followed the manufacturer’s instructions. Slides were scanned by Agilent Microarray Scanner with default settings, Dye channel: Green, Scan resolution=5?m, PMT 100%, 10%, 16bit. Data were extracted with Feature Extraction software 10.7. Raw data were normalized by Quantile algorithm, Gene Spring Software 11.0. The genes with fold change ? 1.5 and P < 0.05 were selected as differentially expressed.

Project description:LuxS is an enzyme involved in the activated methyl cycle and the by-product autoinducer 2 (AI-2) was a quorum sensing signal in some species. In our previous study, the functional LuxS in AI-2 production was verified in the porcine respiratory pathogen Actinobacillus pleuropneumoniae. Enhanced biofilm formation and reduced virulence were observed in the luxS mutant. To comprehensively understand the luxS function, in this study, the transcriptional profiles were compared between the A. pleuropneumoniae luxS mutant and its parental strain in four different growth phases using microarray. Many genes associated with infection were differentially expressed. The biofilm formation genes pgaABC in the luxS mutant were up-regulated in early exponential phase, while 8 genes associated with adhesion were down-regulated in late exponential phase. A group of genes involved in iron acquisition and metabolism were regulated in four growth phases. Further investigations on these virulence traits demonstrated that the luxS mutant showed enhanced biofilm formation and reduced adhesion ability and these effects were not due to lack of AI-2. But AI-2 could increase biofilm formation and adhesion of A. pleuropneumoniae independent of LuxS. Growth under iron restricted condition could be controlled by LuxS through AI-2 production. These results revealed pleiotropic roles of LuxS and AI-2 on A. pleuropneumoniae virulence traits. A. pleuropneumoniae strains were cultured in TSB medium supplemented with 10 M-NM-<g/ml of nicotinamide adenine dinucleotide (NAD) and 10% (v/v)filtered cattle serum at 37M-BM-0C. The samples were collected from early exponential phase, middle exponential phase, late exponential phase and stationary phase respectively and the total RNA were extracted using RNA-Solv Reagent (Omega) according to the manufacturerM-bM-^@M-^Ys instructions. For each time point, four biological replicates were combined into two samples. The intensities were normalized and transformed into log2 value.The fold changes >=1.5 or <=-1.5 were selected as differentially expressed genes.

Project description:LuxS is an enzyme involved in the activated methyl cycle. The by-product of this cycle, autoinducer 2 (AI-2), could be an important quorum sensing signal. LuxS was conserved and regulated many behaviors in different bacteria, but in most species, whether the regulations are related to AI-2 mediated quorum sensing is still unknown. In our previous study, Actinobacillus pleuropneumoniae, the etiologic agent of porcine contagious pleuropneumonia, was found to possess the functional LuxS affecting biofilm formation and virulence. In this study, microarray was used to compare the transcriptional profiles of the A. pleuropneumoniae wildtype strain 4074, luxS mutant and its AI-2 supplemented strain in four different growth phases. The results demonstrated that both LuxS and AI-2 played important roles in metabolism of this bacterium. AI-2 did not recover the gene expression changes caused by luxS deletion but caused more extensive metabolic alterations in the luxS mutant in a concentration dependent manner. Regulations of the genes involved in iron metabolism, carbonhydrate transport and host cell adhesion were validated by real-time RT-PCR and phenotypic investigations under different conditions. The results demonstrated that sugar uptake was repressed by LuxS independent of AI-2. However, iron metabolism, an important process of infection for A. pleuropneumoniae, could be controlled by LuxS through AI-2. Adhesion to host cells was also affected by LuxS and AI-2, but exogenous AI-2 displayed more obvious effects. Our results indicated that both LuxS and AI-2 are essential in the metabolism of A. pleuropneumoniae. The function of LuxS/AI-2 displayed pleiotropic roles in different conditions. AI-2 may not serve as a quorum sensing autoinducer but a metabolite or an environmental cue to affect the metabolism and virulence traits of this important pathogen. A. pleuropneumoniae strains were cultured in TSB medium supplemented with 10 M-NM-<g/ml of nicotinamide adenine dinucleotide (NAD) and 10% (v/v) filtered cattle serum at 37M-BM-0C. For samples from the mutant supplemented with AI-2, 100M-NM-<M and 25M-NM-<M AI-2 precursor (DPD) were added into the medium before early exponential phase as well as one hour before late exponential phase to cover the whole growth phase respectively. The samples were collected from early, middle, late exponential phase and stationary phase respectively and the total RNA were extracted using RNA-Solv Reagent (Omega) according to the manufacturerM-bM-^@M-^Ys instructions. For each time point, four biological replicates were combined into two samples. The intensities were normalized and transformed into log2 value. The values for each time point were averaged and the genes with log2 ratio >=1 or <=-1 were selected as differentially expressed genes.

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Expression data of Actinobacillus pleuropneumoniae 4074 in response to epinephrine and norepinephrine

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