+ Site Statistics
+ Search Articles
+ PDF Full Text Service
How our service works
Request PDF Full Text
+ Follow Us
Follow on Facebook
Follow on Twitter
Follow on LinkedIn
+ Subscribe to Site Feeds
Most Shared
PDF Full Text
+ Translate
+ Recently Requested

The resistance-nodulation-division efflux pump EmhABC influences the production of 2,4-diacetylphloroglucinol in Pseudomonas fluorescens 2P24



The resistance-nodulation-division efflux pump EmhABC influences the production of 2,4-diacetylphloroglucinol in Pseudomonas fluorescens 2P24



Microbiology 156(Pt 1): 39-48



The polyketide metabolite 2,4-diacetylphloroglucinol (2,4-DAPG) plays a major role in the biological control of soil-borne plant diseases by Pseudomonas fluorescens 2P24. Two mutants (PM810 and PM820) with increased extracellular accumulation of 2,4-DAPG were isolated using transposon mutagenesis. The disrupted genes in these two mutants shared >80 % identity with the genes of the EmhR-EmhABC resistance-nodulation-division (RND) efflux system of P. fluorescens cLP6a. The deletion of emhA (PM802), emhB (PM803) or emhC (PM804) genes in strain 2P24 increased the extracellular accumulation of 2,4-DAPG, whereas the deletion of the emhR (PM801) gene decreased the biosynthesis of 2,4-DAPG. The promoter assay confirmed the elevated transcription of emhABC in the EmhR disrupted strain (PM801) and an indirect negative regulation of 2,4-DAPG biosynthetic locus transcription by the EmhABC efflux pump. Induction by exogenous 2,4-DAPG led to remarkable differences in transcription of chromosome-borne phlA : : lacZ fusion in PM901 and PM811 (emhA(-)) strains. Additionally, the EmhABC system in strain 2P24 was involved in the resistance to a group of toxic compounds, including ampicillin, chloramphenicol, tetracycline, ethidium bromide and crystal violet. In conclusion, our results suggest that the EmhABC system is an important element that influences the production of antibiotic 2,4-DAPG and enhances resistance to toxic compounds in P. fluorescens 2P24.

Please choose payment method:






(PDF emailed within 0-6 h: $19.90)

Accession: 035923479

Download citation: RISBibTeXText

PMID: 19833777

DOI: 10.1099/mic.0.031161-0


Related references

The EmhABC efflux pump in Pseudomonas fluorescens LP6a is involved in naphthalene tolerance but not efflux. Applied Microbiology and Biotechnology 97(6): 2587-2596, 2013

Mutations in the central cavity and periplasmic domain affect efflux activity of the resistance-nodulation-division pump EmhB from Pseudomonas fluorescens cLP6a. Journal of Bacteriology 188(1): 115-123, 2006

Physico-chemical factors affect chloramphenicol efflux and EmhABC efflux pump expression in Pseudomonas fluorescens cLP6a. Research in Microbiology 164(2): 172-180, 2013

An alternative physiological role for the EmhABC efflux pump in Pseudomonas fluorescens cLP6a. Bmc Microbiology 11: 252, 2011

Posttranscriptional regulation of 2,4-diacetylphloroglucinol production by GidA and TrmE in Pseudomonas fluorescens 2P24. Applied and Environmental Microbiology 80(13): 3972-3981, 2014

The EmhABC efflux pump decreases the efficiency of phenanthrene biodegradation by Pseudomonas fluorescens strain LP6a. Applied Microbiology and Biotechnology 95(3): 757-766, 2012

Multiple-level regulation of 2,4-diacetylphloroglucinol production by the sigma regulator PsrA in Pseudomonas fluorescens 2P24. Plos one 7(11): E50149, 2012

Effect of the hfq gene on 2,4-diacetylphloroglucinol production and the PcoI/PcoR quorum-sensing system in Pseudomonas fluorescens 2P24. Fems Microbiology Letters 309(1): 16-24, 2010

Experimental evidence on the functional agent of 2,4-diacetylphloroglucinol in Biocontrol activity of Pseudomonas fluorescens 2P24. Weishengwu Xuebao 44(5): 663-666, 2004

Role of the membrane fusion protein in the assembly of resistance-nodulation-cell division multidrug efflux pump in Pseudomonas aeruginosa. Biochemical and Biophysical Research Communications 322(2): 483-489, 2004

Localization of the outer membrane subunit OprM of resistance-nodulation-cell division family multicomponent efflux pump in Pseudomonas aeruginosa. Journal of Biological Chemistry 275(39): 30064-8, 2000

Identification and characterization of the emhABC efflux system for polycyclic aromatic hydrocarbons in Pseudomonas fluorescens cLP6a. Journal of Bacteriology 185(21): 6233-6240, 2003

Contribution of resistance-nodulation-division efflux pump operon smeU1-V-W-U2-X to multidrug resistance of Stenotrophomonas maltophilia. Antimicrobial Agents and ChemoTherapy 55(12): 5826-5833, 2011

Inducible Expression of a Resistance-Nodulation-Division-Type Efflux Pump in Staphylococcus aureus Provides Resistance to Linoleic and Arachidonic Acids. Journal of Bacteriology 197(11): 1893-1905, 2015

Resistance-nodulation-cell division-type efflux pump involved in aminoglycoside resistance in Acinetobacter baumannii strain BM4454. Antimicrobial Agents and ChemoTherapy 45(12): 3375-3380, 2001