Publications

role of the transporter-like sensor kinase cbra in histidine uptake and signal transduction.	cbra is an atypical sensor kinase found in pseudomonas. the autokinase domain is connected to a putative transporter of the sodium/solute symporter family (sssf). cbra functions together with its cognate response regulator, cbrb, and plays an important role in nutrient acquisition, including regulation of hut genes for the utilization of histidine and its derivative, urocanate. here we report on the findings of a genetic and biochemical analysis of cbra with a focus on the function of the putati ...	2015	26148710
the mannitol utilization system of the marine bacterium zobellia galactanivorans.	mannitol is a polyol that occurs in a wide range of living organisms, where it fulfills different physiological roles. in particular, mannitol can account for as much as 20 to 30% of the dry weight of brown algae and is likely to be an important source of carbon for marine heterotrophic bacteria. zobellia galactanivorans (flavobacteriia) is a model for the study of pathways involved in the degradation of seaweed carbohydrates. annotation of its genome revealed the presence of genes potentially i ...	2015	25548051
arabinose and protocatechuate catabolism genes are important for growth of rhizobium leguminosarum biovar viciae in the pea rhizosphere.	to form nitrogen-fixing nodules on pea roots, rhizobium leguminosarum biovar viciae must be competitive in the rhizosphere. our aim was to identify genes important for rhizosphere fitness.	2015	26166901
lipopolysaccharide o-chain core region required for cellular cohesion and compaction of in vitro and root biofilms developed by rhizobium leguminosarum.	the formation of biofilms is an important survival strategy allowing rhizobia to live on soil particles and plant roots. within the microcolonies of the biofilm developed by rhizobium leguminosarum, rhizobial cells interact tightly through lateral and polar connections, forming organized and compact cell aggregates. these microcolonies are embedded in a biofilm matrix, whose main component is the acidic exopolysaccharide (eps). our work shows that the o-chain core region of the r. leguminosarum ...	2015	25416773
the absence of protein y4ys affects negatively the abundance of t3ss mesorhizobium loti secretin, rhcc2, in bacterial membranes.	mesorhizobium loti maff303099 has a functional type iii secretion system (t3ss) that is involved in the determination of nodulation competitiveness on lotus. the m. loti t3ss cluster contains gene y4ys (mlr8765) that codes for a protein of unknown function (y4ys). a mutation in the y4ys gene favors the m. loti symbiotic competitive ability on lotus tenuis cv. esmeralda and affects negatively the secretion of proteins through t3ss. here we localize y4ys in the bacterial membrane using a translati ...	2015	25688250
the yhs-domain of an adenylyl cyclase from mycobacterium phlei is a probable copper-sensor module.	yhs-domains are small protein modules which have been proposed to bind transition-metal ions like the related trash-domains. they are found in a variety of enzymes including copper-transporting atpases and adenylyl cyclases. here we investigate a class iiic adenylyl cyclase from mycobacterium phlei which contains a c-terminal yhs-domain linked to the catalytic domain by a peptide of 8 amino acids. we expressed the isolated catalytic domain and the full-length enzyme in e. coli. the catalytic dom ...	2015	26512893
plant growth-promoting bacteria as inoculants in agricultural soils.	plant-microbe interactions in the rhizosphere are the determinants of plant health, productivity and soil fertility. plant growth-promoting bacteria (pgpb) are bacteria that can enhance plant growth and protect plants from disease and abiotic stresses through a wide variety of mechanisms; those that establish close associations with plants, such as the endophytes, could be more successful in plant growth promotion. several important bacterial characteristics, such as biological nitrogen fixation ...	2015	26537605
dna microarray-based identification of genes regulated by ntrc in bradyrhizobium japonicum.	the bradyrhizobium japonicum ntrbc two-component system is a critical regulator of cellular nitrogen metabolism, including the acquisition and catabolism of nitrogenous compounds. to better define the roles of this system, genome-wide transcriptional profiling was performed to identify the ntrc regulon during the response to nitrogen limitation. upon cells perceiving low intracellular nitrogen, they stimulate the phosphorylation of ntrc, which induces genes responsible for alteration of the core ...	2015	26025905
dephosphorylated npr is involved in an envelope stress response of escherichia coli.	besides the canonical phosphoenolpyruvate-dependent phosphotransferase system (pts) for carbohydrate transport, most proteobacteria possess the so-called nitrogen pts (pts(ntr)) that transfers a phosphate group from phosphoenolpyruvate (pep) over enzyme i(ntr) (ei(ntr)) and npr to enzyme iia(ntr) (eiia(ntr)). the pts(ntr) lacks membrane-bound components and functions exclusively in a regulatory capacity. while eiia(ntr) has been implicated in a variety of cellular processes such as potassium hom ...	2015	25701731
a single serine residue determines selectivity to monovalent metal ions in metalloregulators of the merr family.	merr metalloregulators alleviate toxicity caused by an excess of metal ions, such as copper, zinc, mercury, lead, cadmium, silver, or gold, by triggering the expression of specific efflux or detoxification systems upon metal detection. the sensor protein binds the inducer metal ion by using two conserved cysteine residues at the c-terminal metal-binding loop (mbl). divalent metal ion sensors, such as merr and zntr, require a third cysteine residue, located at the beginning of the dimerization (α ...	2015	25691529
heterologous production of curcuminoids.	curcuminoids, components of the rhizome of turmeric, show several beneficial biological activities, including anticarcinogenic, antioxidant, anti-inflammatory, and antitumor activities. despite their numerous pharmaceutically important properties, the low natural abundance of curcuminoids represents a major drawback for their use as therapeutic agents. therefore, they represent attractive targets for heterologous production and metabolic engineering. the understanding of biosynthesis of curcumin ...	2015	25631288
a jaz protein in astragalus sinicus interacts with a leghemoglobin through the tify domain and is involved in nodule development and nitrogen fixation.	leghemoglobins (lbs) play an important role in legumes-rhizobia symbiosis. lbs bind o2 and protect nitrogenase activity from damage by o2 in nodules, therefore, they are regarded as a marker of active nitrogen fixation in nodules. additionally, lbs are involved in the nitric oxide (no) signaling pathway, acting as a no scavenger during nodule development and nitrogen fixation. however, regulators responsible for lb expression and modulation of lb activity have not been characterized. in our prev ...	2015	26460857
the sugar kinase that is necessary for the catabolism of rhamnose in rhizobium leguminosarum directly interacts with the abc transporter necessary for rhamnose transport.	rhamnose catabolism in rhizobium leguminosarum was found to be necessary for the ability of the organism to compete for nodule occupancy. characterization of the locus necessary for the catabolism of rhamnose showed that the transport of rhamnose was dependent upon a carbohydrate uptake transporter 2 (cut2) abc transporter encoded by rhastpq and on the presence of rhak, a protein known to have sugar kinase activity. a linker-scanning mutagenesis analysis of rhak showed that the kinase and transp ...	2015	26416834
loss of the nodule-specific cysteine rich peptide, ncr169, abolishes symbiotic nitrogen fixation in the medicago truncatula dnf7 mutant.	host compatible rhizobia induce the formation of legume root nodules, symbiotic organs within which intracellular bacteria are present in plant-derived membrane compartments termed symbiosomes. in medicago truncatula nodules, the sinorhizobium microsymbionts undergo an irreversible differentiation process leading to the development of elongated polyploid noncultivable nitrogen fixing bacteroids that convert atmospheric dinitrogen into ammonia. this terminal differentiation is directed by the hos ...	2015	26401023
knotted1-like homeobox 3: a new regulator of symbiotic nodule development.	knox transcription factors (tfs) regulate different aspects of plant development essentially through their effects on phytohormone metabolism. in particular, knox tf shootmeristemless activates the cytokinin biosynthesis isopentenyl transferase (ipt) genes in the shoot apical meristem. however, the role of knox tfs in symbiotic nodule development and their possible effects on phytohormone metabolism during nodulation have not been studied to date. cytokinin is a well-known regulator of nodule de ...	2015	26351356
identification of a core set of rhizobial infection genes using data from single cell-types.	genome-wide expression studies on nodulation have varied in their scale from entire root systems to dissected nodules or root sections containing nodule primordia (np). more recently efforts have focused on developing methods for isolation of root hairs from infected plants and the application of laser-capture microdissection technology to nodules. here we analyze two published data sets to identify a core set of infection genes that are expressed in the nodule and in root hairs during infection ...	2015	26284091
remodeling of the infection chamber before infection thread formation reveals a two-step mechanism for rhizobial entry into the host legume root hair.	in many legumes, root entry of symbiotic nitrogen-fixing rhizobia occurs via host-constructed tubular tip-growing structures known as infection threads (its). here, we have used a confocal microscopy live-tissue imaging approach to investigate early stages of it formation in medicago truncatula root hairs (rhs) expressing fluorescent protein fusion reporters. this has revealed that its only initiate 10 to 20 h after the completion of rh curling, by which time major modifications have occurred wi ...	2015	25659382
mini-tn7 vectors for stable expression of diguanylate cyclase pled* in gram-negative bacteria.	the cyclic diguanylate (c-di-gmp) is currently considered an ubiquitous second messenger in bacteria that influences a wide range of cellular processes. one of the methodological approaches to unravel c-di-gmp regulatory networks involves raising the c-di-gmp intracellular levels, e.g. by expressing a diguanylate cyclase (dgc), to provoke phenotypic changes.	2015	26415513
gene expression of type vi secretion system associated with environmental survival in acidovorax avenae subsp. avenae by principle component analysis.	valine glycine repeat g (vgrg) proteins are regarded as one of two effectors of type vi secretion system (t6ss) which is a complex multi-component secretion system. in this study, potential biological roles of t6ss structural and vgrg genes in a rice bacterial pathogen, acidovorax avenae subsp. avenae (aaa) rs-1, were evaluated under seven stress conditions using principle component analysis of gene expression. the results showed that growth of the pathogen was reduced by h₂o₂ and paraquat-induc ...	2015	26378528
legume-rhizobia signal exchange: promiscuity and environmental effects.	although signal exchange between legumes and their rhizobia is among the best-known examples of this biological process, most of the more characterized data comes from just a few legume species and environmental stresses. although a relative wealth of information is available for some model legumes and some of the major pulses such as soybean, little is known about tropical legumes. this relative disparity in current knowledge is also apparent in the research on the effects of environmental stre ...	2015	26441880
quinol oxidase encoded by cyoabcd in rhizobium etli cfn42 is regulated by actsr and is crucial for growth at low ph or low iron conditions.	rhizobium etli aerobically respires with several terminal oxidases. the quinol oxidase (cyo) encoded by cyoabcd is needed for efficient adaptation to low oxygen conditions and cyo transcription is upregulated at low oxygen. this study sought to determine how transcription of the cyo operon is regulated. the 5' sequence upstream of cyo was analysed in silico and revealed putative binding sites for actr of the actsr two-component regulatory system. the expression of cyo was decreased in an actsr m ...	2015	26297648
draft genome sequence of the bacteriocin-producing bradyrhizobium japonicum strain fn1.	bradyrhizobium japonicum strain fn1 was found to produce bacteriocin-like zones of clearing when tested against other strains of bradyrhizbia. the genome was sequenced, and several putative bacteriocin-producing genes, in addition to the expected genes involved in nodulation and nitrogen fixation, were identified.	2015	26227594
symbiotic potential and survival of native rhizobia kept on different carriers.	native rhizobia are ideal for use as commercial legume inoculants. the characteristics of the carrier used to store the inoculants are important for the survival and symbiotic potential of the rhizobia. the objective of this study was to investigate the effects of peat (peat), perlite sugarcane bagasse (psb), carboxymethyl cellulose plus starch (cmcs), and yeast extract mannitol supplemented with mannitol (yemm) on the survival, nodulation potential and n2 fixation capacity of the native strains ...	2015	26413054
a bioinformatics insight to rhizobial globins: gene identification and mapping, polypeptide sequence and phenetic analysis, and protein modeling.	globins (glbs) are proteins widely distributed in organisms. three evolutionary families have been identified in glbs: the m, s and t glb families. the m glbs include flavohemoglobins (fhbs) and single-domain glbs (sdgbs); the s glbs include globin-coupled sensors (gcss), protoglobins and sensor single domain globins, and the t glbs include truncated glbs (thbs). structurally, the m and s glbs exhibit 3/3-folding whereas the t glbs exhibit 2/2-folding. glbs are widespread in bacteria, including ...	2015	26594329
regulatory nodd1 and nodd2 genes of rhizobium tropici strain ciat 899 and their roles in the early stages of molecular signaling and host-legume nodulation.	nodulation and symbiotic nitrogen fixation are mediated by several genes, both of the host legume and of the bacterium. the rhizobial regulatory nodd gene plays a critical role, orchestrating the transcription of the other nodulation genes. rhizobium tropici strain ciat 899 is an effective symbiont of several legumes-with an emphasis on common bean (phaseolus vulgaris)-and is unusual in carrying multiple copies of nodd, the roles of which remain to be elucidated.	2015	25880529
leghemoglobin is nitrated in functional legume nodules in a tyrosine residue within the heme cavity by a nitrite/peroxide-dependent mechanism.	protein tyrosine (tyr) nitration is a post-translational modification yielding 3-nitrotyrosine (no2 -tyr). formation of no2 -tyr is generally considered as a marker of nitro-oxidative stress and is involved in some human pathophysiological disorders, but has been poorly studied in plants. leghemoglobin (lb) is an abundant hemeprotein of legume nodules that plays an essential role as an o2 transporter. liquid chromatography coupled to tandem mass spectrometry was used for a targeted search and qu ...	2015	25603991
a genomic encyclopedia of the root nodule bacteria: assessing genetic diversity through a systematic biogeographic survey.	root nodule bacteria are free-living soil bacteria, belonging to diverse genera within the alphaproteobacteria and betaproteobacteria, that have the capacity to form nitrogen-fixing symbioses with legumes. the symbiosis is specific and is governed by signaling molecules produced from both host and bacteria. sequencing of several model rnb genomes has provided valuable insights into the genetic basis of symbiosis. however, the small number of sequenced rnb genomes available does not currently ref ...	2015	25685260
identification of ferredoxin ii as a major calcium binding protein in the nitrogen-fixing symbiotic bacterium mesorhizobium loti.	legumes establish with rhizobial bacteria a nitrogen-fixing symbiosis which is of the utmost importance for both plant nutrition and a sustainable agriculture. calcium is known to act as a key intracellular messenger in the perception of symbiotic signals by both the host plant and the microbial partner. regulation of intracellular free ca(2+) concentration, which is a fundamental prerequisite for any ca(2+)-based signalling system, is accomplished by complex mechanisms including ca(2+) binding ...	2015	25648224
ensifer-mediated transformation: an efficient non-agrobacterium protocol for the genetic modification of rice.	while agrobacterium-mediated transformation (amt) remains the most widely used technique for gene transfer in plants, interest exists for the use of non-agrobacterium gene delivery systems due to freedom-to-operate issues that remain with amt across several jurisdictions. in addition, the plant pathogenic mode of action of agrobacterium tumefaciens significantly increases the costs to passage engineered cultivars through the regulatory process. ensifer adhaerens (ov14) is a soil-related bacteriu ...	2015	26543735
bacterial genospecies that are not ecologically coherent: population genomics of rhizobium leguminosarum.	biological species may remain distinct because of genetic isolation or ecological adaptation, but these two aspects do not always coincide. to establish the nature of the species boundary within a local bacterial population, we characterized a sympatric population of the bacterium rhizobium leguminosarum by genomic sequencing of 72 isolates. although all strains have 16s rrna typical of r. leguminosarum, they fall into five genospecies by the criterion of average nucleotide identity (ani). many ...	2015	25589577
genomic features separating ten strains of neorhizobium galegae with different symbiotic phenotypes.	the symbiotic phenotype of neorhizobium galegae, with strains specifically fixing nitrogen with either galega orientalis or g. officinalis, has made it a target in research on determinants of host specificity in nitrogen fixation. the genomic differences between representative strains of the two symbiovars are, however, relatively small. this introduced a need for a dataset representing a larger bacterial population in order to make better conclusions on characteristics typical for a subset of t ...	2015	25933608
evolution of intra-specific regulatory networks in a multipartite bacterial genome.	reconstruction of the regulatory network is an important step in understanding how organisms control the expression of gene products and therefore phenotypes. recent studies have pointed out the importance of regulatory network plasticity in bacterial adaptation and evolution. the evolution of such networks within and outside the species boundary is however still obscure. sinorhizobium meliloti is an ideal species for such study, having three large replicons, many genomes available and a signifi ...	2015	26340565
nitrite-oxidizing bacterium nitrobacter winogradskyi produces n-acyl-homoserine lactone autoinducers.	nitrobacter winogradskyi is a chemolithotrophic bacterium that plays a role in the nitrogen cycle by oxidizing nitrite to nitrate. here, we demonstrate a functional n-acyl-homoserine lactone (acyl-hsl) synthase in this bacterium. the n. winogradskyi genome contains genes encoding a putative acyl-hsl autoinducer synthase (nwi0626, nwii) and a putative acyl-hsl autoinducer receptor (nwi0627, nwir) with amino acid sequences 38 to 78% identical to those in rhodopseudomonas palustris and other rhizob ...	2015	26092466
transcriptome profiling of a rhizobium leguminosarum bv. trifolii rosr mutant reveals the role of the transcriptional regulator rosr in motility, synthesis of cell-surface components, and other cellular processes.	rhizobium leguminosarum bv. trifolii is a soil bacterium capable of establishing a symbiotic relationship with red clover (trifolium pratense). the presence of surface polysaccharides and other extracellular components as well as motility and competitiveness are essential traits for both adaptation of this bacterium to changing environmental conditions and successful infection of host plant roots. the r. leguminosarum bv. trifolii rosr gene encodes a protein belonging to the family of ros/mucr t ...	2015	26715155
sinorhizobium meliloti phage φm9 defines a new group of t4 superfamily phages with unusual genomic features but a common t=16 capsid.	relatively little is known about the phages that infect agriculturally important nitrogen-fixing rhizobial bacteria. here we report the genome and cryo-electron microscopy structure of the sinorhizobium meliloti-infecting t4 superfamily phage φm9. this phage and its close relative rhizobium phage vb_rlem_p10vf define a new group of t4 superfamily phages. these phages are distinctly different from the recently characterized cyanophage-like s. meliloti phages of the φm12 group. structurally, φm9 h ...	2015	26311868
physiological and molecular aspects of tolerance to environmental constraints in grain and forage legumes.	despite the agronomical and environmental advantages of the cultivation of legumes, their production is limited by various environmental constraints such as water or nutrient limitation, frost or heat stress and soil salinity, which may be the result of pedoclimatic conditions, intensive use of agricultural lands, decline in soil fertility and environmental degradation. the development of more sustainable agroecosystems that are resilient to environmental constraints will therefore require bette ...	2015	26287163
pseudomonas aeruginosa mifs-mifr two-component system is specific for α-ketoglutarate utilization.	pseudomonas aeruginosa is a gram-negative, metabolically versatile opportunistic pathogen that elaborates a multitude of virulence factors, and is extraordinarily resistant to a gamut of clinically significant antibiotics. this ability, in part, is mediated by two-component regulatory systems (tcs) that play a crucial role in modulating virulence mechanisms and metabolism. mifs (pa5512) and mifr (pa5511) form one such tcs implicated in biofilm formation. mifs is a sensor kinase whereas mifr belo ...	2015	26114434
identification and classification of rhizobia by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry.	mass spectrometry (ms) has been widely used for specific, sensitive and rapid analysis of proteins and has shown a high potential for bacterial identification and characterization. type strains of four species of rhizobia and escherichia coli dh5α were employed as reference bacteria to optimize various parameters for identification and classification of species of rhizobia by matrix-assisted laser desorption/ionization time-of-flight ms (maldi tof ms). the parameters optimized included culture m ...	2015	26500417
novel mixed-linkage β-glucan activated by c-di-gmp in sinorhizobium meliloti.	an artificial increase of cyclic diguanylate (c-di-gmp) levels in sinorhizobium meliloti 8530, a bacterium that does not carry known cellulose synthesis genes, leads to overproduction of a substance that binds the dyes congo red and calcofluor. sugar composition and methylation analyses and nmr studies identified this compound as a linear mixed-linkage (1 → 3)(1 → 4)-β-d-glucan (ml β-glucan), not previously described in bacteria but resembling ml β-glucans found in plants and lichens. this uniqu ...	2015	25650430
phytostabilization of moderate copper contaminated soils using co-inoculation of vicia faba with plant growth promoting bacteria.	there is a need to conduct research on the selection of microbial isolates from rhizosphere of plants growing on heavy metal contaminated soils for specific restoration programs. this article suggest a consortium of bacteria combining rhizobium sp. ccnwsx0481, rhizobium leguminosarum bv. viciae, enterobacter cloacae and pseudomonas sp. 2(2010) that was examined for the ability to promote vicia faba.l. growth when cultivated on the vineyard of soil moderately contaminated with copper. data showed ...	2015	24338717
against friend and foe: type 6 effectors in plant-associated bacteria.	bacterial secretion systems play critical roles in communication with neighboring bacteria and in the modulation of host immune responses via the secretion of small proteins called effectors. several secretion systems have been identified and these are denoted types i-vii. of these, the type vi secretion system (t6ss) and its effectors were only recently elucidated. most studies on the role and significance of the t6ss and its effectors have focused on human pathogens. in this review, type 6 eff ...	2015	25732741
rhizobium leguminosarum hupe is a highly-specific diffusion facilitator for nickel uptake.	bacteria require nickel transporters for the synthesis of ni-containing metalloenzymes in natural, low nickel habitats. in this work we carry out functional and topological characterization of rhizobium leguminosarum hupe, a nickel permease required for the provision of this element for [nife] hydrogenase synthesis. expression studies in the escherichia coli nikabcde mutant strain hyd723 revealed that hupe is a medium-affinity permease (apparent km 227 ± 21 nm; vmax 49 ± 21 pmol ni(2+) min(-1) m ...	2015	25652141
rapd-inferred genetic variability of some indigenous rhizobium leguminosarum isolates from red clover (trifolium pratense l.) nodules.	the application of commercial rhizobial inoculants to legume crops is proving to be an alternative to synthetic fertilizer use. the challenge for sustainable agriculture resides in the compatibility between crop, inoculants and environmental conditions. the evaluation of symbiotic efficiency and genetic diversity of indigenous rhizobial strains could lead to the development of better inoculants and increased crop production. the genetic variability of 32 wild indigenous rhizobial isolates was as ...	2015	26344027
pseudorhizobium pelagicum gen. nov., sp. nov. isolated from a pelagic mediterranean zone.	two novel alphaproteobacteria strains, r1-200b4(t) and r2-400b4, were isolated from the mediterranean sea off the coast of alicante in spain. the phylogenetic analysis of the 16s rrna gene showed that they are related to members of family rhizobiaceae. the 16s rrna gene sequence of strain r1-200b4(t) presents 97.0% and 95.6% similarity with respect to the type strains of the type species from genera neorhizobium and rhizobium, neorhizobium galegae hambi 540(t) and rhizobium leguminosarum usda 23 ...	2015	26078205
cicer canariense, an endemic legume to the canary islands, is nodulated in mainland spain by fast-growing strains from symbiovar trifolii phylogenetically related to rhizobium leguminosarum.	cicer canariense is a threatened endemic legume from the canary islands where it can be nodulated by mesorhizobial strains from the symbiovar ciceri, which is the common worldwide endosymbiont of cicer arietinum linked to the genus mesorhizobium. however, when c. canariense was cultivated in a soil from mainland spain, where the symbiovar ciceri is present, only fast-growing rhizobial strains were unexpectedly isolated from its nodules. these strains were classified into the genus rhizobium by a ...	2015	26032249
structural elucidation of the outer core tetrasaccharide isolated from the lps of rhizobium leguminosarum bv. trifolii strain 24.	the outer core oligosaccharide (os) was isolated from the lipopolysaccharide (lps) of rhizobium leguminosarum bv. trifolii strain 24 after smith degradation and then studied by sugar and methylation analyses along with nmr and mass spectrometry methods. negative-ion electrospray (esi-ms) mass spectrum showed two molecular ions at m/z 686.3 and 728.3, which corresponded to the core os having the composition rha2quinackdh. the mass difference between both ions indicated that the higher molecule ma ...	2015	25880336
[population structure of the clover rhizobia rhizobium leguminosarum bv. trifolii upon transition from soil into the nodular niche].	high-throughput sequencing of the amplicon gene library revealed variations in the population structure of clover rhizobia (rhizobium leguminosarum bv. trifolii) upon transition from soil into the root nodules of the host plant (trifolium-hybridum). analysis of rhizobial-diversity using the noda gene revealed 3258 and 1449 nucleotide sequences (allelic-variants) for the soil and root nodule population, respectively. they were combined into 29 operational taxonomic units (otu) according to the 97 ...	2015	25844461
[influence of calcium and rhizobial infections (rhizobium leguminosarum) on the dynamics of nitric oxide (no) content in roots of etiolated pea (pisum sativum l.) seedlings].	the effect of exogenous calcium (ca2+) and rhizobial infections (rhizobium leguminosarum bv viceae) on the dynamics of the level of nitric oxide (no) was studied in cross cuts of roots of two-day-old etiolated pea seedlings (pisum sativum l.) using a daf-2da fluorescent probe. fluctuations of the no level, indicating the presence of a rhythm in the generation of no in roots, were observed during the incubation of seedlings in water, a cacl2 solution, and with rhizobial infections. exogenous fact ...	2015	25726667
genetic diversity of rhizobium from nodulating beans grown in a variety of mediterranean climate soils of chile.	in spite of potentially being an important source of rhizobial diversity and a key determinant of common bean productivity, there is a paucity of data on rhizobium genetic variation and species composition in the important bean producing area of chile and only one species has been documented (rhizobium leguminosarum). in this study, 240 rhizobium isolates from torcaza bean (phaseolus vulgaris l.) nodules established in the highest bean producing area in chile (33°34's-70°38'w and 37°36's-71°47'w ...	2015	25533847
counter-transcribed rnas of rhizobium leguminosarum repabc plasmids exert incompatibility effects only when highly expressed.	the six plasmids of rhizobium leguminosarum vf39sm comprise nearly 35% of the bacterium's genome and are all repabc replicons. the repabc operons of the three largest plasmids of vf39sm were found to have strong incompatibility determinants in the non-protein coding regions. however, in all three repabc operons, the intergenic region between repb and repc was the strongest incompatibility factor; this intergenic region has been shown, for most repabc plasmids, to encode a counter-transcribed rna ...	2015	25530178
population genomics analysis of legume host preference for specific rhizobial genotypes in the rhizobium leguminosarum bv. viciae symbioses.	rhizobium leguminosarum bv. viciae establishes root nodule symbioses with several legume genera. although most isolates are equally effective in establishing symbioses with all host genera, previous evidence suggests that hosts select specific rhizobial genotypes among those present in the soil. we have used population genomics to further investigate this observation. pisum sativum, lens culinaris, vicia sativa, and v. faba plants were used to trap rhizobia from a well-characterized soil, and po ...	2015	25514682
genetic differentiation of trifolium repens microsymbionts deriving from zn-pb waste-heap and control area in poland.	the aim of this work was to determine the genetic structure of rhizobium leguminosarum bv. trifolii population isolated from root nodules of trifolium repens growing in heavy metal contaminated bolesław waste-heap area and compare it with that of an unpolluted control bolestraszyce population. the 684-bp long dinitrogenase reductase (nifh) gene fragments were amplified in a pcr reaction and then sequenced. an analysis of nifh gene amplicons of 21 rhizobial strains from each of the studied popula ...	2015	25400035
rhizobium sophorae sp. nov. and rhizobium sophoriradicis sp. nov., nitrogen-fixing rhizobial symbionts of the medicinal legume sophora flavescens.	five bacterial strains representing 45 isolates originated from root nodules of the medicinal legume sophora flavescens were defined as two novel groups in the genus rhizobium based on their phylogenetic relationships estimated from 16s rrna genes and the housekeeping genes reca, glnii and atpd. these groups were distantly related to rhizobium leguminosarum usda 2370(t) (95.6 % similarity for group i) and rhizobium phaseoli atcc 14482(t) (93.4 % similarity for group ii) in multilocus sequence an ...	2015	25385989
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 gr ...	2015	25370751
mechanisms behind bacteria induced plant growth promotion and zn accumulation in brassica juncea.	the growth and metal-extraction efficiency of plants exposed to toxic metals has been reported to be enhanced by inoculating plants with certain bacteria but the mechanisms behind this process remain unclear. we report results from glasshouse experiments on brassica juncea plants exposed to 400mgznkg(-1) that investigated the abilities of pseudomonas brassicacearum and rhizobium leguminosarum to promote growth, coupled with synchrotron based μxanes analysis to probe zn speciation in the plant ro ...	2015	25464287
[characteristics of natural selection in populations of nodule bacteria (rhizobium leguminosarum) interacting with different host plants].	using high throughput sequencing of the noda gene, we studied the population dynamics of rhizobium leguminosarum (bv. viciae, bv. trifolii) in rhizospheric and nodular subpopulations associated with the leguminous plants representing different cross-inoculation groups (vicia sativa, lathyrus pratensis of the vetch/vetchling/pea group and trifolium hybridum of the clover group). the "rhizosphere-nodules" transitions result in either an increase or decrease in the frequencies of 10 of the 23 opera ...	2015	27169225
site-specific distribution and competitive ability of indigenous bean-nodulating rhizobia isolated from organic fields in minnesota.	organic dry bean production systems have received increasing interest in many regions of the us, including minnesota. thus, improving biological n2 fixation would be highly beneficial for organic crop production. to date, only limited work has been done to select efficient n2-fixing rhizobia for organic dry bean production. in this study, soil samples from 25 organic fields in minnesota, with a previous cropping history of dry beans, soybeans or both, were collected during may to july 2012. gene ...	2015	26403588
rhizobial diversity and nodulation characteristics of the extremely promiscuous legume sophora flavescens.	in present study, we report our extensive survey on the diversity and biogeography of rhizobia associated with sophora flavescens, a sophocarpidine (matrine)-containing medicinal legume. we additionally investigated the cross nodulation, infection pattern, light and electron microscopies of root nodule sections of s. flavescens infected by various rhizobia. seventeen genospecies of rhizobia belonging to five genera with seven types of symbiotic nodc genes were found to nodulate s. flavescens in ...	2015	26389798
rhizobium ecuadorense sp. nov., an indigenous n2-fixing symbiont of the ecuadorian common bean (phaseolus vulgaris l.) genetic pool.	there are two major centres of genetic diversification of common bean (phaseolus vilgaris l.), the mesoamerican and the andean, and the legume is capable of establishing nitrogen-fixing symbioses with several rhizobia; rhizobium etli seems to be the dominant species in both centres. another genetic pool of common bean, in peru and ecuador, is receiving increasing attention, and studies of microsymbionts from the region can help to increase our knowledge about coevolution of this symbiosis. we ha ...	2015	26297041
[antioxidative function of katg gene in rhizobium leguminosarum].	catalase-peroxidase katg can protect bacteria from damage of reactive oxygen species. this study investigated the antioxidative function of catalase - peroxidase gene katg in rhizobium leguminosarum 3841.	2015	26710603
[influence of environmental factors on the generation of nitric oxide in the roots of etiolated pea seedlings].	the article studies the nitric oxide (no) levels in the roots of etiolated seedlings of garden peas (pisum sativum l.) using the daf-2da fluorescent probe and fluorescent microscopy. cross sections of roots of 100-150 microm (the site of a root which is 10-15 mm from the apex) are analyzed. it is shown that the level of no in the roots after 24 h increased by more than a factor of 2 in the versions with nano2 and sodium nitroprusside. at feeding the seedlings with kno3, a peak in the accumulatio ...	2015	22567891
[influence of rhizobial (rhizobium leguminosarum) inoculation and calcium ions on the nadph oxidase activity in roots of etiolated pea (pisum sativum l.) seedlings].	changes in the functional activity of the nadph oxidase in the microsomal fraction of roots of etiolated pea seedlings, caused by rhizobial inoculation and calcium ions (ca2+), are shown. the enzyme activity in a medium with an exogenous source of ca2+ (cacl2, 100 microm) fluctuated, increasing 5 to 20 min and decreasing 10 and 30 min after addition. a calcium chelator (ethylene glycol tetraacetic acid (edta), 100 microm) potentiated the decrease in the enzyme activity in the presence of exogeno ...	2015	23882941
mgte from rhizobium leguminosarum is a mg²⁺ channel essential for growth at low ph and n2 fixation on specific plants.	mgte is predicted to be a rhizobium leguminosarum channel and is essential for growth when both mg²⁺ is limiting and the ph is low. n₂was only fixed at 8% of the rate of wild type when the crop legume pisum sativum was inoculated with an mgte mutant of r. leguminosarum and, although bacteroids were present, they were few in number and not fully developed. r. leguminosarum mgte was also essential for n₂fixation on the native legume vicia hirsuta but not when in symbiosis with vicia faba. the impo ...	2015	26422403
characterization of the temperate phage vb_rlem_ppf1 and its site-specific integration into the rhizobium leguminosarum f1 genome.	bacteriophages may play an important role in regulating population size and diversity of the root nodule symbiont rhizobium leguminosarum, as well as participating in horizontal gene transfer. although phages that infect this species have been isolated in the past, our knowledge of their molecular biology, and especially of genome composition, is extremely limited, and this lack of information impacts on the ability to assess phage population dynamics and limits potential agricultural applicatio ...	2016	26377943
[the effect of cadmium on the efficiency of development of legume-rhizobium symbiosis].	screening of nodule bacteria (rhizobia) forming symbiotic relationships with legumes has been performed in order to isolate strains resistant to cadmium ions in a wide range of concentrations (6-132 mg/kg). the effect ofcadmium salts (6, 12, 24 mg/kg) on the legume-rhizobium symbiosis ofthe pea pisum sativum l. with rhizobium leguminosarum and of the fodder galega galega orientalis lam. with rhizobium galegae has been studied under experimental laboratory conditions. no statistically significant ...	2016	26638242
rhizobium acidisoli sp. nov., isolated from root nodules of phaseolus vulgaris in acid soils.	two gram-negative, aerobic, non-motile, rod-shaped bacterial strains, fh13t and fh23, representing a novel group of rhizobium isolated from root nodules of phaseolus vulgaris in mexico, were studied by a polyphasic analysis. phylogeny of 16s rrna gene sequences revealed them to be members of the genus rhizobium related most closely to 'rhizobium anhuiense' ccbau 23252 (99.7 % similarity), rhizobium leguminosarum usda 2370t (98.6 %), and rhizobium sophorae ccbau 03386t and others ( ≤ 98.3 %). in ...	2016	26530784
measurements of carbon utilization by single bacterial species in sterile soil: insights into rhizobium spp.	the aim of this work was to develop a tool to investigate the influence of soil factors on carbon utilization activity of single micro-organisms.	2016	27155348
genetic diversity of rhizobia nodulating native vicia spp. in sweden.	despite the recognition that rhizobium leguminosarum sv. viciae is the most common symbiont of vicia species worldwide, there is no available information on rhizobia nodulating native vicia species in sweden. we have therefore studied the genetic diversity and phylogeny of root nodule bacteria isolated from v. cracca, v. hirsuta, v. sepium, v. tetrasperma and v. sylvatica growing in different locations in sweden as well as an isolate each from v. cracca in tromsø, norway, and v. multicaulis in s ...	2016	26924220
multiplicity of sulfate and molybdate transporters and their role in nitrogen fixation in rhizobium leguminosarum bv. viciae rlv3841.	rhizobium leguminosarum rlv3841 contains at least three sulfate transporters, i.e., sulabcd, sulp1 and sulp2, and a single molybdate transporter, modabc. sulabcd is a high-affinity transporter whose mutation prevented growth on a limiting sulfate concentration, while sulp1 and sulp2 appear to be low-affinity sulfate transporters. modabc is the sole high-affinity molybdate transport system and is essential for growth with no3(-) as a nitrogen source on limiting levels of molybdate (<0.25 μm). how ...	2016	26812045
phylogenetic distribution and evolutionary pattern of an α-proteobacterial small rna gene that controls polyhydroxybutyrate accumulation in sinorhizobium meliloti.	it has become clear that srnas play relevant regulatory functions in bacteria. however, a comprehensive understanding of their biological roles considering evolutionary aspects has not been achieved for most of them. thus, we have characterized the evolutionary and phylogenetic aspects of the sinorhizobium meliloti mmgr gene encoding the small rna mmgr, which has been recently reported to be involved in the regulation of polyhydroxybutyrate accumulation in this bacterium. we constructed a covari ...	2016	27033949
repb proteins of the multipartite rhizobium leguminosarum bv. trifolii genome discriminate between centromere-like pars sequences for plasmid segregational stability.	the plasmids of the rhizobiaceae family members and other alphaproteobacteria are usually large, low copy-number and contain all elements necessary for active segregation and replication located in one operon comprising repabc genes. the genome of rhizobium leguminosarum bv. trifolii ta1 (rtta1) consists of a chromosome and four plasmids (prleta1a-d) with repabc operons. in this work, centromere-binding repb proteins of four rtta1 plasmids were studied. stability assays of the truncated derivati ...	2016	27480612
lipogenesis and redox balance in nitrogen-fixing pea bacteroids.	within legume root nodules, rhizobia differentiate into bacteroids that oxidize host-derived dicarboxylic acids, which is assumed to occur via the tricarboxylic acid (tca) cycle to generate nad(p)h for reduction of n2 metabolic flux analysis of laboratory-grown rhizobium leguminosarum showed that the flux from [(13)c]succinate was consistent with respiration of an obligate aerobe growing on a tca cycle intermediate as the sole carbon source. however, the instability of fragile pea bacteroids pre ...	2016	27501983
local genetic structure and worldwide phylogenetic position of symbiotic rhizobium leguminosarum strains associated with a traditional cultivated crop, vicia ervilia, from northern morocco.	a total of 212 symbiotic bacteria were isolated from nodules of vicia ervilia, a traditional crop cultivated in northern morocco. the isolates were recovered from 10 different sites, trapped each time with the local cultivar grown in the same field. four loci were sequenced in order to characterize the isolates, including two housekeeping genes (reca and glnii), one plasmidic symbiotic gene (nodc) and one locus from another plasmid (prl11). in several isolates, two different copies of glnii were ...	2016	27394068
symbiont abundance is more important than pre-infection partner choice in a rhizobium - legume mutualism.	it is known that the genetic diversity of conspecific rhizobia present in root nodules differs greatly among populations of a legume species, which has led to the suggestion that both dispersal limitation and the local environment affect rhizobial genotypic composition. however, it remains unclear whether rhizobial genotypes residing in root nodules are representative of the entire population of compatible symbiotic rhizobia. since symbiotic preferences differ among legume populations, the genet ...	2016	27269381
[secretion of phenolic compounds into root exudates of pea seedlings upon inoculation with rhizobium leguminosarum bv. viceae or pseudomonas siringae pv. pisi].	the content of apigenin, naringenin, pisatin, dibutyl-ortho-phthalate, and n-phenyl-2-naphthyl-amine were assayed in root exudates of pea (pisum sativum l.) seedlings one day after their inoculation with rhizobium leguminosarum, bv. viceae or pseudomonas siringae pv. pisi, which represent, respectively, mutualistic and antagonistic strategies of interaction with a host plant. after inoculation with either bacteria, the concentrations of apigenin and pisatin in the root exudates were equal, where ...	2016	27266251
new alkaline lipase from rhizomucor variabilis: biochemical properties and stability in the presence of microbial eps.	a new strain of rhizomucor variabilis producing an active extracellular lipase was identified and characterized in the present studies. the culture conditions were optimized and the highest lipase production amounting to 136 u/ml was achieved after 4 days of cultivation. the optimum ph (5.5) and temperature (28 °c) were determined as the best conditions for r. variabilis lipase production. the isolated enzyme preparation exhibited maximum activity at 40 °c and ph 8.0. lipase from r. variabilis w ...	2016	25643732
characterization and mutagenesis of two novel iron-sulphur cluster pentonate dehydratases.	we describe here the identification and characterization of two novel enzymes belonging to the ilvd/edd protein family, the d-xylonate dehydratase from caulobacter crescentus, cc xydht, (ec 4.2.1.82), and the l-arabonate dehydratase from rhizobium leguminosarum bv. trifolii, rl ardht (ec 4.2.1.25), that produce the corresponding 2-keto-3-deoxy-sugar acids. there is only a very limited amount of characterization data available on pentonate dehydratases, even though the enzymes from these oxidativ ...	2016	27102126
[role of bacterial adhesin rapa1 in formation of efficient symbiosis of rhizobium leguminosarum with bean plants].	bacterial adhesins, the proteins responsible for attachment of plant growth-promoting rhizobacteria to plant roots, are involved in formation of stable associative symbioses. in the present work enhanced expression of the rapa1 adhesin gene in rhizobium leguminosarum pvu5 was shown to improve the efficiency of nodulation on bean roots inoculated with the modified strain. the rapa1 gene was cloned into the pjn105turbo plasmid, this construct was used for transformation of r. leguminosarum pvu5, b ...	2016	26964360
unexpected formation of n'-phenyl-thiophosphorohydrazidic acid o,s-dimethyl ester from acephate: chemical, biotechnical and computational study.	by the nucleophilic attack of phenylhydrazine on acephate in aqueous medium, a stable product n'-phenyl-thiophosphorohydrazidic acid o,s-dimethyl ester (1) was obtained and characterized by elemental, spectral and thermal analysis. thermodynamic parameters, ea, δh°, δs° and δg°, have found to be 62.15, -67.95, -0.068 and -20.05 kj mol(-1) according to the coats-redfern equation. analysis of interaction of 1 with bsa protein was done by using the uv-vis and ftir spectroscopic methods. the observe ...	2016	28330071
rhizobium leguminosarum symbiovar trifolii, ensifer numidicus and mesorhizobium amorphae symbiovar ciceri (or mesorhizobium loti) are new endosymbiotic bacteria of lens culinaris medik.	a total of 142 rhizobial bacteria were isolated from root nodules of lens culinaris medik endemic to tunisia and they belonged to the species rhizobium leguminosarum, and for the first time to ensifer and mesorhizobium, genera never previously described as microsymbionts of lentil. phenotypically, our results indicate that l. culinaris medik strains showed heterogenic responses to the different phenotypic features and they effectively nodulated their original host. based on the concatenation of ...	2016	27267929
rhizobium strains differ considerably in outer membrane permeability and polymyxin b resistance.	six rhizobium (rhizobium leguminosarum bv. trifolii ta1, sinorhizobium meliloti 1021, mesorhizobium huakuii ifo 15243(t), ochrobactrum lupini lup 21(t), bradyrhizobium japonicum usda110 and b. elkanii usda 76) and two escherichia coli strains (e. coli atcc 25922 and e. coli hb 101) were compared in respect to polymyxin b and edta resistance, as well as bacterial outer membrane (om) permeability to a fluorescent hydrophobic agent (n-phenyl-1-naphthylamine - npn). tem (transmission electron micros ...	2016	27253495
inoculation of new rhizobial isolates improve nutrient uptake and growth of bean (phaseolus vulgaris) and arugula (eruca sativa).	in the current agricultural model, the massive use of chemical fertilizer causes environmental and economic losses. inoculation of plant-growth-promoting (pgp) nitrogen-fixing bacteria is an alternative to the use of nitrogen, phosphorus and potassium fertilizers. in this study, rhizobia strains isolated from common bean (phaseolus vulgaris) root nodules were evaluated in an effort to identify an efficient nitrogen-fixing rhizobia strain able to improve bean germination and growth.	2016	26564333
mixed planting with a leguminous plant outperforms bacteria in promoting growth of a metal remediating plant through histidine synthesis.	the effectiveness of plant growth promoting bacteria (pgpb) in improving metal phytoremediation is still limited by stunted plant growth under high soil metal concentrations. meanwhile, mixed planting with leguminous plants is known to improve yield in nutrient deficient soils but the use of a metal tolerant legume to enhance metal tolerance of a phytoremediator has not been explored. we compared the use of pseudomonas brassicacearum, rhizobium leguminosarum, and the metal tolerant leguminous pl ...	2016	26682469
phylogenetic diversity of ammopiptanthus rhizobia and distribution of rhizobia associated with ammopiptanthus mongolicus in diverse regions of northwest china.	aiming to investigate the diversity and distribution of rhizobia associated with ammopiptanthus, an endangered evergreen legume widely distributed in deserts, we characterized a total of 219 nodule isolates from nine sampling sites in northwest china with different soil characteristics based upon restriction fragment length polymorphism (rflp) analysis of 16s ribosomal rna (rrna) and symbiotic genes (nodc and nifh). ten isolates representing different 16s rrna-rflp types were selected for furthe ...	2016	27079453
host factors influencing the retrohoming pathway of group ii intron rmint1, which has an intron-encoded protein naturally devoid of endonuclease activity.	bacterial group ii introns are self-splicing catalytic rnas and mobile retroelements that have an open reading frame encoding an intron-encoded protein (iep) with reverse transcriptase (rt) and rna splicing or maturase activity. some ieps carry a dna endonuclease (en) domain, which is required to cleave the bottom strand downstream from the intron-insertion site for target dna-primed reverse transcription (tprt) of the inserted intron rna. host factors complete the insertion of the intron. by co ...	2016	27588750
transcriptome analysis revealed that a quorum sensing system regulates the transfer of the pat megaplasmid in agrobacterium tumefaciens.	agrobacterium tumefaciens strain p4 is atypical, as the strain is not pathogenic and produces a for this species unusual quorum sensing signal, identified as n-(3-hydroxy-octanoyl)-homoserine lactone (3oh,c8-hsl).	2016	27543103
metabolic modelling reveals the specialization of secondary replicons for niche adaptation in sinorhizobium meliloti.	the genome of about 10% of bacterial species is divided among two or more large chromosome-sized replicons. the contribution of each replicon to the microbial life cycle (for example, environmental adaptations and/or niche switching) remains unclear. here we report a genome-scale metabolic model of the legume symbiont sinorhizobium meliloti that is integrated with carbon utilization data for 1,500 genes with 192 carbon substrates. growth of s. meliloti is modelled in three ecological niches (bul ...	2016	27447951
a single amino acid substitution in a chitinase of the legume medicago truncatula is sufficient to gain nod-factor hydrolase activity.	the symbiotic interaction between nitrogen-fixing rhizobia and legumes depends on lipo-chitooligosaccharidic nod-factors (nfs). the nf hydrolase mtnfh1 of medicago truncatula is a symbiotic enzyme that hydrolytically inactivates nfs with a c16 : 2 acyl chain produced by the microsymbiont sinorhizobium meliloti 1021. mtnfh1 is related to class v chitinases (glycoside hydrolase family 18) but lacks chitinase activity. here, we investigated the substrate specificity of mtnfh1-related proteins. mtch ...	2016	27383628
a brazilian marseillevirus is the founding member of a lineage in family marseilleviridae.	in 2003, acanthamoeba polyphaga mimivirus (apmv) was discovered as parasitizing acanthamoeba. it was revealed to exhibit remarkable features, especially odd genomic characteristics, and founded viral family mimiviridae. subsequently, a second family of giant amoebal viruses was described, marseilleviridae, whose prototype member is marseillevirus, discovered in 2009. currently, the genomes of seven different members of this family have been fully sequenced. previous phylogenetic analysis suggest ...	2016	26978387
microevolution analysis of bacillus coahuilensis unveils differences in phosphorus acquisition strategies and their regulation.	bacterial genomes undergo numerous events of gene losses and gains that generate genome variability among strains of the same species (microevolution). our aim was to compare the genomes and relevant phenotypes of three bacillus coahuilensis strains from two oligotrophic hydrological systems in the cuatro ciénegas basin (méxico), to unveil the environmental challenges that this species cope with, and the microevolutionary differences in these genotypes. since the strains were isolated from a low ...	2016	26903955
the absence of the n-acyl-homoserine-lactone autoinducer synthase genes trai and ngri increases the copy number of the symbiotic plasmid in sinorhizobium fredii ngr234.	plant-released flavonoids induce the transcription of symbiotic genes in rhizobia and one of the first bacterial responses is the synthesis of so called nod factors. they are responsible for the initial root hair curling during onset of root nodule development. this signal exchange is believed to be essential for initiating the plant symbiosis with rhizobia affiliated with the alphaproteobacteria. here, we provide evidence that in the broad host range strain sinorhizobium fredii ngr234 the compl ...	2016	27917168
reclassification of the taxonomic status of semia3007 isolated in mexico b-11a mex as rhizobium leguminosarum bv. viceae by bioinformatic tools.	evidence based on genomic sequences is extremely important to confirm the phylogenetic relationships within the rhizobium group. semia3007 was analyzed within the mesorhizobium groups to define the underlying causes of taxonomic identification. we previously used biochemical tests and phenotypic taxonomic methods to identify bacteria, which can lead to erroneous classification. an improved understanding of bacterial strains such as the mesorhizobium genus would increase our knowledge of classifi ...	2016	27814683
surface properties of wild-type rhizobium leguminosarum bv. trifolii strain 24.2 and its derivatives with different extracellular polysaccharide content.	rhizobium leguminosarum bv. trifolii is a soil bacterium able to establish symbiosis with agriculturally important legumes, i.e., clover plants (trifolium spp.). cell surface properties of rhizobia play an essential role in their interaction with both biotic and abiotic surfaces. physicochemical properties of bacterial cells are underpinned by the chemical composition of their envelope surrounding the cells, and depend on various environmental conditions. in this study, we performed a comprehens ...	2016	27760230
assembly and transfer of tripartite integrative and conjugative genetic elements.	integrative and conjugative elements (ices) are ubiquitous mobile genetic elements present as "genomic islands" within bacterial chromosomes. symbiosis islands are ices that convert nonsymbiotic mesorhizobia into symbionts of legumes. here we report the discovery of symbiosis ices that exist as three separate chromosomal regions when integrated in their hosts, but through recombination assemble as a single circular ice for conjugative transfer. whole-genome comparisons revealed exconjugants deri ...	2016	27733511
growth rate of and gene expression in bradyrhizobium diazoefficiens usda110 due to a mutation in blr7984, a tetr family transcriptional regulator gene.	previous transcriptome analyses have suggested that a gene cluster including a transcriptional regulator (blr7984) of the tetracycline repressor family was markedly down-regulated in symbiosis. since blr7984 is annotated to be the transcriptional repressor, we hypothesized that it is involved in the repression of genes in the genomic cluster including blr7984 in symbiotic bacteroids. in order to examine the function and involvement of the blr7984 gene in differentiation into bacteroids, we compa ...	2016	27383683
cyanobacteria and eukaryotic algae use different chemical variants of vitamin b12.	eukaryotic microalgae and prokaryotic cyanobacteria are the major components of the phytoplankton. determining factors that govern growth of these primary producers, and how they interact, is therefore essential to understanding aquatic ecosystem productivity. over half of microalgal species representing marine and freshwater habitats require for growth the corrinoid cofactor b12, which is synthesized de novo only by certain prokaryotes, including the majority of cyanobacteria. there are several ...	2016	27040778
plant pathogens affecting the establishment of plant-symbiont interaction.		2016	26834779
the use of transposon insertion sequencing to interrogate the core functional genome of the legume symbiont rhizobium leguminosarum.	the free-living legume symbiont rhizobium leguminosarum is of significant economic value because of its ability to provide fixed nitrogen to globally important leguminous food crops, such as peas and lentils. discovery based research into the genetics and physiology of r. leguminosarum provides the foundational knowledge necessary for understanding the bacterium's complex lifestyle, necessary for augmenting its use in an agricultural setting. transposon insertion sequencing (inseq) facilitates h ...	2016	27920770
the regulatory protein rosr affects rhizobium leguminosarum bv. trifolii protein profiles, cell surface properties, and symbiosis with clover.	rhizobium leguminosarum bv. trifolii is capable of establishing a symbiotic relationship with plants from the genus trifolium. previously, a regulatory protein encoded by rosr was identified and characterized in this bacterium. rosr possesses a cys2-his2-type zinc finger motif and belongs to ros/mucr family of rhizobial transcriptional regulators. transcriptome profiling of the rosr mutant revealed a role of this protein in several cellular processes, including the synthesis of cell-surface comp ...	2016	27602024
exopolysaccharide production by sinorhizobium fredii hh103 is repressed by genistein in a nodd1-dependent manner.	in the rhizobia-legume symbiotic interaction, bacterial surface polysaccharides, such as exopolysaccharide (eps), lipopolysaccharide (lps), k-antigen polysaccharide (kps) or cyclic glucans (cg), appear to play crucial roles either acting as signals required for the progression of the interaction and/or preventing host defence mechanisms. the symbiotic significance of each of these polysaccharides varies depending on the specific rhizobia-legume couple. in this work we show that the production of ...	2016	27486751