Pseudomonas syringae Differentiates into Phenotypically Distinct Subpopulations During Colonization of a Plant Host

Rufi�n, Jos� S.; S�nchez-Romero, Mar�a Antonia; L�pez-M�rquez, Diego; Macho, Alberto P.; Mansfield, John W.; Arnold, Dawn L.; Ruiz-Albert, Javier; Casades�s, Josep; Beuz�n, Carmen R.

Abstract

© 2016 Society for Applied Microbiology and John Wiley & Sons Ltd Bacterial microcolonies with heterogeneous sizes are formed during colonization of Phaseolus vulgaris by Pseudomonas syringae. Heterogeneous expression of structural and regulatory components of the P. syringae type III secretion system (T3SS), essential for colonization of the host apoplast and disease development, is likewise detected within the plant apoplast. T3SS expression is bistable in the homogeneous environment of nutrient-limited T3SS-inducing medium, suggesting that subpopulation formation is not a response to different environmental cues. T3SS bistability is reversible, indicating a non-genetic origin, and the T3SSHIGH and T3SSLOW subpopulations show differences in virulence. T3SS bistability requires the transcriptional activator HrpL, the double negative regulatory loop established by HrpV and HrpG, and may be enhanced through a positive feedback loop involving HrpA, the main component of the T3SS pilus. To our knowledge, this is the first example of phenotypic heterogeneity in the expression of virulence determinants during colonization of a non-mammalian host.

• Journal Article Type: Article
• Acceptance Date: Aug 9, 2016
• Online Publication Date: Aug 11, 2016
• Publication Date: Oct 1, 2016
• Deposit Date: Aug 11, 2016
• Publicly Available Date: Sep 9, 2017
• Journal: Environmental Microbiology
• Print ISSN: 1462-2912
• Electronic ISSN: 1462-2920
• Publisher: Wiley
• Peer Reviewed: Peer Reviewed
• Volume: 18
• Issue: 10
• Pages: 3593-3605
• DOI: https://doi.org/10.1111/1462-2920.13497
• Keywords: phenotypic heterogeneity, bacterial pathogen, bistability, plant host, 27 type III secretion system, bacterial effectors, virulence, host adaptation
• Public URL: https://uwe-repository.worktribe.com/output/909051
• Publisher URL: http://dx.doi.org/10.1111/1462-2920.13497
• Additional Information: Additional Information : This is the peer reviewed version of the following article: Rufian, J. S., Sanchez-Romero, M.-A., Lopez-Marquez, D., Macho, A. P., Mansfield, J. W., Arnold, D. L., Ruiz-Albert, J., Casadesus, J. and Beuzon, C. R. (2016) Pseudomonas syringae differentiates into phenotypically distinct subpopulations during colonization of a plant host. Environmental Microbiology, which has been published in final form at http://dx.doi.org/10.1111/1462-2920.13497. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving.
• Contract Date: Aug 11, 2016