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| Status |
Public on Nov 15, 2011 |
| Title |
Expression data of Actinobacillus pleuropneumoniae 4074, the ΔluxS mutant and AI-2 supplemented ΔluxS mutant |
| Organism |
Actinobacillus pleuropneumoniae |
| Experiment type |
Expression profiling by array
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| Summary |
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.
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| Overall design |
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.
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| Contributor(s) |
Li L, Xu Z, Zhou R, Chen H |
| Citation missing |
Has this study been published? Please login to update or notify GEO. |
| Submission date |
Apr 12, 2010 |
| Last update date |
Sep 03, 2014 |
| Contact name |
Lu Li |
| E-mail(s) |
sakura.tree@163.com, xuzf@mail.hzau.edu.cn, xuzhuofei@sohu.com, kobe2071@tom.com
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| Organization name |
Huazhong Agricultural University
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| Street address |
Shizishan Street 1
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| City |
Wuhan |
| State/province |
Hubei |
| ZIP/Postal code |
430070 |
| Country |
China |
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| Platforms (1) |
| GPL9691 |
Agilent-019883 Actinobacillus pleuropneumoniae expression array |
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| Samples (32)
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| Relations |
| BioProject |
PRJNA126565 |
| Supplementary file |
Size |
Download |
File type/resource |
| GSE21300_RAW.tar |
73.5 Mb |
(http)(custom) |
TAR (of TXT) |
| Processed data included within Sample table |
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