Editor: Christoph Tebbe
Quorum-sensing effects in the antagonistic rhizosphere bacterium Serratia plymuthica HRO-C48
Article first published online: 24 DEC 2008
© 2008 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved
FEMS Microbiology Ecology
Volume 67, Issue 3, pages 468–478, March 2009
How to Cite
Müller, H., Westendorf, C., Leitner, E., Chernin, L., Riedel, K., Schmidt, S., Eberl, L. and Berg, G. (2009), Quorum-sensing effects in the antagonistic rhizosphere bacterium Serratia plymuthica HRO-C48. FEMS Microbiology Ecology, 67: 468–478. doi: 10.1111/j.1574-6941.2008.00635.x
- Issue published online: 2 FEB 2009
- Article first published online: 24 DEC 2008
- Received 11 March 2008; revised 7 October 2008; accepted 18 October 2008.First published online 24 December 2008.
- Serratia plymuthica;
- quorum sensing;
- volatile organic compounds;
- antagonistic mechanisms
The rhizosphere-associated bacterium Serratia plymuthica HRO-C48 is not only able to suppress symptoms caused by soil-borne pathogens but is also able to stimulate growth of plants. Detailed knowledge about the underlying mechanisms and regulation are crucial for the application in biocontrol strategies. To analyse the influence of N-acyl homoserine lactone (AHL)-mediated communication on the biocontrol activity, the AHL-degrading lactonase AiiA was heterologously expressed in the strain, resulting in abolished AHL production. The comparative analysis of the wild type and AHL negative mutants led to the identification of new AHL-regulated phenotypes. In the pathosystem Verticillium dahliae–oilseed rape, the essential role of AHL-mediated signaling for disease suppression was demonstrated. In vitro, the regulatory function of AHLs in the synthesis of the plant growth hormone indole-3-acetic acid is shown for the first time. Additionally, swimming motility was found to be negatively AHL regulated. In contrast, production of extracellular hydrolytic enzymes is shown to be positively AHL-regulated. HRO-C48 emits a broad spectrum of volatile organic compounds that are involved in antifungal activity and, interestingly, whose relative abundances are influenced by quorum sensing (QS). This study shows that QS is crucial for biocontrol activity of S. plymuthica and discusses the impact for the application of the strain as a biocontrol agent.