An epigenetic switch activates bacterial quorum sensing and horizontal transfer of an integrative and conjugative element.

Horizontal transfer of the integrative and conjugative element ICEMlSymR7A converts non-symbiotic Mesorhizobium spp. into nitrogen-fixing legume symbionts. Here, we discover subpopulations of Mesorhizobium japonicum R7A become epigenetically primed for quorum-sensing (QS) and QS-activated horizontal transfer.

Transcriptomics reveal core activities of the plant growth-promoting bacterium RAY209 during interaction with canola and soybean roots.

The plant growth-promoting rhizobacterium RAY209 is capable of establishing strong root attachment during early plant development at 7 days post-inoculation. The transcriptional response of RAY209 was measured using RNA-seq during early (day 2) and sustained (day 7) root colonization of canola plants, capturing RAY209 differentiation from a medium-suspended cell state to a strongly root-attached cell state. Transcriptomic data was collected in an identical manner during RAY209 interaction with soybean roots to explore the putative root colonization response to this globally relevant crop.

Complete Genome Sequence of RAY209, a Plant Growth-Promoting Rhizobacterium for Canola and Soybean.

Herein, we report the genome sequence of strain RAY209, a plant growth-promoting rhizobacterium that is used in commercial inoculants for canola and soybean. The genome of RAY209 has a consensus of 6,528,879 bp and an estimated 5,721 coding sequences.

Temporal variation in the prevalence and species richness of Campylobacter spp. in a prairie watershed impacted by urban and agricultural mixed inputs.

Campylobacter spp. are a substantial cause of gastroenteritis worldwide. Human infection can result from ingestion of contaminated food or water from a variety of sources, including the consumption of fresh produce that is contaminated with the pathogen via the use of contaminated irrigation water.

Draft Genome Sequence and Annotation of Phyllosphere-Persisting Salmonella enterica subsp. enterica Serovar Livingstone Strain CKY-S4, Isolated from an Urban Lake in Regina, Canada.

Here, we report the first draft genome sequence of Salmonella enterica subsp. enterica serovar Livingstone. This S.

A previously uncharacterized tetratricopeptide-repeat-containing protein is involved in cell envelope function in Rhizobium leguminosarum.

Rhizobium leguminosarum is a soil bacterium that is an intracellular symbiont of leguminous plants through the formation of nitrogen-fixing root nodules. Due to the changing environments that rhizobia encounter, the cell is often faced with a variety of cell altering stressors that can compromise the cell envelope integrity. A previously uncharacterized operon (RL3499-RL3502) has been linked to proper cell envelope function, and mutants display pleiotropic phenotypes including an inability to grow on peptide-rich media.

Legume seed exudates and Physcomitrella patens extracts influence swarming behavior in Rhizobium leguminosarum.

Plants are known to secrete chemical compounds that can change the behavior of rhizosphere-inhabiting bacteria. We investigated the effects of extracts from legume host plants on the swarming behavior of Rhizobium leguminosarum bv. viciae.

Evaluation of two quantitative PCR assays using Bacteroidales and mitochondrial DNA markers for tracking dog fecal contamination in waterbodies.

This study describes a comparative performance evaluation of two qPCR assays targeting a dog-associated Bacteroidales 16S rRNA genetic marker (CanBac-UCD) and a dog mitochondrial DNA (mtDNA) marker. The same fecal and environmental samples were assayed for the two markers thereby allowing direct comparison. A wide range of non-target species including, human, pig, horse, deer, mountain goat, bison, caribou, and moose were tested.

Persistence of host-associated Bacteroidales gene markers and their quantitative detection in an urban and agricultural mixed prairie watershed.

Microbial source tracking is an emerging tool developed to protect water sources from faecal pollution. In this study, we evaluated the suitability of real time-quantitative PCR (qPCR) Taqman assays developed for detection of host-associated Bacteroidales markers in a prairie watershed. The qPCR primers and probes used in this study exhibited high accuracy (88-96% sensitivity and ≥ 99% host specificity) in detecting Bacteroidales spp.

Mutation of a broadly conserved operon (RL3499-RL3502) from Rhizobium leguminosarum biovar viciae causes defects in cell morphology and envelope integrity.

The bacterial cell envelope is of critical importance to the function and survival of the cell; it acts as a barrier against harmful toxins while allowing the flow of nutrients into the cell. It also serves as a point of physical contact between a bacterial cell and its host. Hence, the cell envelope of Rhizobium leguminosarum is critical to cell survival under both free-living and symbiotic conditions.

Characterization and functional analysis of seven flagellin genes in Rhizobium leguminosarum bv. viciae. Characterization of R. leguminosarum flagellins.

Background: Rhizobium leguminosarum bv. viciae establishes symbiotic nitrogen fixing partnerships with plant species belonging to the Tribe Vicieae, which includes the genera Vicia, Lathyrus, Pisum and Lens. Motility and chemotaxis are important in the ecology of R.

Characterization of swarming motility in Rhizobium leguminosarum bv. viciae.

We have characterized swarming motility in Rhizobium leguminosarum strains 3841 and VF39SM. Swarming was dependent on growth on energy-rich media, and both agar concentration and incubation temperature were critical parameters for surface migration. A cell density-dependent lag period was observed before swarming motility was initiated.

Regulation of flagellar, motility and chemotaxis genes in Rhizobium leguminosarum by the VisN/R-Rem cascade.

In this paper, we describe the regulatory roles of VisN, VisR and Rem in the expression of flagellar, motility and chemotaxis genes in Rhizobium leguminosarum biovar viciae strains VF39SM and 3841. Individual mutations in the genes encoding these proteins resulted in a loss of motility and an absence of flagella, indicating that these regulatory genes are essential for flagellar synthesis and function. Transcriptional experiments involving gusA-gene fusions in wild-type and mutant backgrounds were performed to identify the genes under VisN/R and Rem regulation.