Next Article in Journal
Isolation and Characterization of Ftsz Genes in Cassava
Next Article in Special Issue
Requirements for Efficient Thiosulfate Oxidation in Bradyrhizobium diazoefficiens
Previous Article in Journal / Special Issue
NAD1 Controls Defense-Like Responses in Medicago truncatula Symbiotic Nitrogen Fixing Nodules Following Rhizobial Colonization in a BacA-Independent Manner
Article Menu
Issue 12 (December) cover image

Export Article

Open AccessArticle
Genes 2017, 8(12), 389; https://doi.org/10.3390/genes8120389

Transcriptome Analysis of Paraburkholderia phymatum under Nitrogen Starvation and during Symbiosis with Phaseolus Vulgaris

Department of Plant and Microbial Biology, University of Zurich, CH-8057 Zurich, Switzerland
*
Author to whom correspondence should be addressed.
Received: 31 October 2017 / Revised: 29 November 2017 / Accepted: 4 December 2017 / Published: 15 December 2017
(This article belongs to the Special Issue Genetics and Genomics of the Rhizobium-Legume Symbiosis)
View Full-Text   |   Download PDF [2050 KB, uploaded 15 December 2017]   |  

Abstract

Paraburkholderia phymatum belongs to the β-subclass of proteobacteria. It has recently been shown to be able to nodulate and fix nitrogen in symbiosis with several mimosoid and papilionoid legumes. In contrast to the symbiosis of legumes with α-proteobacteria, very little is known about the molecular determinants underlying the successful establishment of this mutualistic relationship with β-proteobacteria. In this study, we performed an RNA-sequencing (RNA-seq) analysis of free-living P. phymatum growing under nitrogen-replete and -limited conditions, the latter partially mimicking the situation in nitrogen-deprived soils. Among the genes upregulated under nitrogen limitation, we found genes involved in exopolysaccharides production and in motility, two traits relevant for plant root infection. Next, RNA-seq data of P. phymatum grown under free-living conditions and from symbiotic root nodules of Phaseolus vulgaris (common bean) were generated and compared. Among the genes highly upregulated during symbiosis, we identified—besides the nif gene cluster—an operon encoding a potential cytochrome o ubiquinol oxidase (Bphy_3646-49). Bean root nodules induced by a cyoB mutant strain showed reduced nitrogenase and nitrogen fixation abilities, suggesting an important role of the cytochrome for respiration inside the nodule. The analysis of mutant strains for the RNA polymerase transcription factor RpoN (σ54) and its activator NifA indicated that—similar to the situation in α-rhizobia—P. phymatum RpoN and NifA are key regulators during symbiosis with P. vulgaris. View Full-Text
Keywords: differential gene expression; rhizobia; infection; nitrogen fixation; nodulation; NifA; cytochrome; sigma factor; exopolysaccharides; motility differential gene expression; rhizobia; infection; nitrogen fixation; nodulation; NifA; cytochrome; sigma factor; exopolysaccharides; motility
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. (CC BY 4.0).

Supplementary material

SciFeed

Share & Cite This Article

MDPI and ACS Style

Lardi, M.; Liu, Y.; Purtschert, G.; Bolzan de Campos, S.; Pessi, G. Transcriptome Analysis of Paraburkholderia phymatum under Nitrogen Starvation and during Symbiosis with Phaseolus Vulgaris. Genes 2017, 8, 389.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Genes EISSN 2073-4425 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top