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Title: Expression data of Actinobacillus pleuropneumoniae 4074, the ΔluxS mutant and AI-2 supplemented ΔluxS mutant      
dateReleased:
11-15-2011
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 μg/ml of nicotinamide adenine dinucleotide (NAD) and 10% (v/v) filtered cattle serum at 37°C. For samples from the mutant supplemented with AI-2, 100μM and 25μM 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 manufacturer’s 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.
privacy:
not applicable
aggregation:
instance of dataset
ID:
E-GEOD-21300
refinement:
raw
alternateIdentifiers:
21300
keywords:
functional genomics
dateModified:
04-18-2012
availability:
available
types:
gene expression
name:
Actinobacillus pleuropneumoniae
ID:
A-GEOD-9691
name:
Agilent A. pleuropneumoniae 15 K expression array
accessURL: https://www.ebi.ac.uk/arrayexpress/files/E-GEOD-21300/E-GEOD-21300.raw.1.zip
storedIn:
ArrayExpress
qualifier:
gzip compressed
format:
TXT
accessType:
download
authentication:
none
authorization:
none
accessURL: https://www.ebi.ac.uk/arrayexpress/files/E-GEOD-21300/E-GEOD-21300.processed.1.zip
storedIn:
ArrayExpress
qualifier:
gzip compressed
format:
TXT
accessType:
download
authentication:
none
authorization:
none
accessURL: https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE21300
storedIn:
Gene Expression Omnibus
qualifier:
not compressed
format:
HTML
accessType:
landing page
primary:
true
authentication:
none
authorization:
none
abbreviation:
EBI
homePage: http://www.ebi.ac.uk/
ID:
SCR:004727
name:
European Bioinformatics Institute
homePage: https://www.ebi.ac.uk/arrayexpress/
ID:
SCR:002964
name:
ArrayExpress

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