Identification and functional analysis of recent IS transposition events in rhizobia.

Rhizobia are alpha- and beta- Proteobacteria that, through the establishment of symbiotic interactions with leguminous plants, are able to fix atmospheric nitrogen as ammonium. The successful establishment of a symbiotic interaction is highly dependent on the availability of nitrogen sources in the soil, and on the specific rhizobia strain. Insertion sequences (ISs) are simple transposable genetic elements that can move to different locations within the host genome and are known to play an important evolutionary role, contributing to genome plasticity by acting as recombination hot-spots, and disrupting coding and regulatory sequences.

Comparative Proteomic Analysis Revealing ActJ-Regulated Proteins in .

To adapt to different environmental conditions, relies on finely tuned regulatory networks, most of which are unexplored to date. We recently demonstrated that deletion of the two-component system ActJK renders an acid-vulnerable phenotype in and negatively impacts bacteroid development and nodule occupancy as well. To fully understand the role of ActJ in acid tolerance, wild-type and ΔJ proteomes were compared in the presence or absence of acid stress by nanoflow ultrahigh-performance liquid chromatography coupled to mass spectrometry.

ubiF is involved in acid stress tolerance and symbiotic competitiveness in Rhizobium favelukesii LPU83.

The acidity of soils significantly reduces the productivity of legumes mainly because of the detrimental effects of hydrogen ions on the legume plants, leading to the establishment of an inefficient symbiosis and poor biological nitrogen fixation. We recently reported the analysis of the fully sequenced genome of Rhizobium favelukesii LPU83, an alfalfa-nodulating rhizobium with a remarkable ability to grow, nodulate and compete in acidic conditions. To gain more insight into the genetic mechanisms leading to acid tolerance in R.

Genome mining of Burkholderia ambifaria strain T16, a rhizobacterium able to produce antimicrobial compounds and degrade the mycotoxin fusaric acid.

Burkholderia ambifaria T16 is a bacterium isolated from the rhizosphere of barley plants that showed a remarkable antifungal activity. This strain was also able to degrade fusaric acid (5-Butylpyridine-2-carboxylic acid) and detoxify this mycotoxin in inoculated barley seedlings. Genes and enzymes responsible for fusaric acid degradation have an important biotechnological potential in the control of fungal diseases caused by fusaric acid producers, or in the biodegradation/bio catalysis processes of pyridine derivatives.

The phylogeny of the genus supports its transfer to the family .

The genus encompasses five validly described species belonging to the betaproteobacterial class. Recognized for their potential biotechnological uses, they were first described as belonging to the genus . The phylogeny of the 16S rRNA gene of the original strains as well as newly described species led to a description of these strains within a new bacterial genus, .