Gene expression profiling of Escherichia coli in response to interactions with the lettuce rhizosphere
Article first published online: 20 AUG 2012
© 2012 The Authors Journal of Applied Microbiology © 2012 The Society for Applied Microbiology
Journal of Applied Microbiology
Volume 113, Issue 5, pages 1076–1086, November 2012
How to Cite
Hou, Z., Fink, R.C., Black, E.P., Sugawara, M., Zhang, Z., Diez-Gonzalez, F. and Sadowsky, M.J. (2012), Gene expression profiling of Escherichia coli in response to interactions with the lettuce rhizosphere. Journal of Applied Microbiology, 113: 1076–1086. doi: 10.1111/j.1365-2672.2012.05412.x
- Issue published online: 17 OCT 2012
- Article first published online: 20 AUG 2012
- Accepted manuscript online: 26 JUL 2012 12:15AM EST
- Manuscript Accepted: 21 JUL 2012
- Manuscript Revised: 9 JUL 2012
- Manuscript Received: 4 JUN 2012
- University of Minnesota Healthy Food and Healthy Lives Institute
- Escherichia coli ;
- lettuce rhizosphere;
The objective of this study was to examine transcriptional changes in Escherichia coli when the bacterium was growing in the lettuce rhizoshpere.
Methods and Results
A combination of microarray analyses, colonization assays and confocal microscopy was used to gain a more complete understanding of bacterial genes involved in the colonization and growth of E. coli K12 in the lettuce root rhizosphere using a novel hydroponic assay system. After 3 days of interaction with lettuce roots, E. coli genes involved in protein synthesis, stress responses and attachment were up-regulated. Mutants in curli production (crl, csgA) and flagella synthesis (fliN) had a reduced capacity to attach to roots as determined by bacterial counts and by confocal laser scanning microscopy.
This study indicates that E. coli K12 has the capability to colonize lettuce roots by using attachment genes and can readily adapt to the rhizosphere of lettuce plants.
Significance and Impact of the Study
Results of this study show curli production and biofilm modulation genes are important for rhizosphere colonization and may provide useful targets to disrupt this process. Further studies using pathogenic strains will provide additional information about lettuce–E. coli interactions.