| Autor: |
Dong, Yi-Hu, Zhang, Xi-Fen, Soo, Hui-Meng Linda, Greenberg, Everett P., Zhang, Lian-Hui |
| Předmět: |
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| Zdroj: |
Molecular Microbiology; Jun2005, Vol. 56 Issue 5, p1287-1301, 15p |
| Abstrakt: |
The response regulator PprB and its cognate sensor PprA were recently reported as a two-component regulatory system that controls membrane permeability and antibiotic sensitivity ofPseudomonas aeruginosa. We found that a Tn5insertion mutation inpprBcaused a drastic reduction in virulence factor production and cell motility. A transcriptome analysis revealed that 175 genes were regulated by PprB. Among the 113 PprB-activated genes, 85.5% are known to be activated byN-3-oxo-dodecanoyl-homoserine lactone (OdDHL) andN-butanoyl-homoserine lactone (BHL). In particular, the expression oflasI,rhlIandrhlR, which encode key components of thelasandrhlquorum-sensing (QS) systems, were significantly decreased in thepprBmutant. These data suggest that PprB might regulate QS signal production. Measurement of OdDHL and BHL in cultures of the mutant sustained this hypothesis. By using various OdDHL- or BHL-responsive QS reporter systems, includinglasB–lacZ,lasI–lacZandrsaL–lacZ, we found that the mutation inpprBresulted in a large decrease in the sensitivity ofP. aeruginosato exogenous OdDHL. However, there was no difference in sensitivity to BHL. Further analysis showed that the OdDHL influx was significantly reduced in thepprBmutant. We conclude that PprB is a novel QS modulator that positively regulatesN-acylhomoserine lactone production probably by affecting the OdDHL signal influx and thereby influences global expression of the QS-dependent genes. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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