Publications
| Title | Abstract | Year Filter | PMID(sorted ascending) Filter |
|---|
| correlation between infection by rhizobium leguminosarum and lectin on the surface of pisum sativum l. roots. | the lectin on the surface of 4- and 5-dold pea roots was located by the use of indirect immunofluorescence. specific antibodies raised in rabbits against pea seed isolectin 2, which crossreact with root lectins, were used as primary immunoglobulins and were visualized with fluorescein- or tetramethylrhodamine-isothiocyanate-labeled goat antirabbit immunoglobulin g. lectin was observed on the tips of newly formed, growing root hairs and on epidermal cells located just below the young hairs. on bo ... | 1986 | 24232144 |
| effects of sodium chloride and polyethylene glycol on root-hair infection and nodulation of vicia faba l. plants by rhizobium leguminosarum. | the effects of sodium chloride and polyethylene glycol (peg) on the interaction between rhizobium leguminosarum strain 29d and root hairs of field bean (vicia faba l. cv. maris bead) plants were investigated. two levels each of nacl (50 and 100 mol·m(-3)) and peg (100 and 200 mol·m(-3)) were given at the time of root-hair formation. scanning electron microscopy showed rhizobial attachment and colonization on root-hair tips. adhesion of rhizobia in both lateral and polar orientation, sometimes as ... | 1986 | 24240297 |
| toxin-antitoxin systems: biology, identification, and application. | toxin-antitoxin (ta) systems are small genetic elements composed of a toxin gene and its cognate antitoxin. the toxins of all known ta systems are proteins while the antitoxins are either proteins or non-coding rnas. based on the molecular nature of the antitoxin and its mode of interaction with the toxin the ta modules are currently grouped into five classes. in general, the toxin is more stable than the antitoxin but the latter is expressed to a higher level. if supply of the antitoxin stops, ... | 2013 | 24251069 |
| an underground tale: contribution of microbial activity to plant iron acquisition via ecological processes. | iron (fe) deficiency in crops is a worldwide agricultural problem. plants have evolved several strategies to enhance fe acquisition, but increasing evidence has shown that the intrinsic plant-based strategies alone are insufficient to avoid fe deficiency in fe-limited soils. soil micro-organisms also play a critical role in plant fe acquisition; however, the mechanisms behind their promotion of fe acquisition remain largely unknown. | 2013 | 24265348 |
| an underground tale: contribution of microbial activity to plant iron acquisition via ecological processes. | iron (fe) deficiency in crops is a worldwide agricultural problem. plants have evolved several strategies to enhance fe acquisition, but increasing evidence has shown that the intrinsic plant-based strategies alone are insufficient to avoid fe deficiency in fe-limited soils. soil micro-organisms also play a critical role in plant fe acquisition; however, the mechanisms behind their promotion of fe acquisition remain largely unknown. | 2013 | 24265348 |
| growth regulators, rhizobium and nodulation in peas : the cytokinin content of a wild-type and a ti-plasmid-containing strain of r. leguminosarum. | the cytokinin content of roots and nodules of pea and the culture supernatants from two strains of rhizobium leguminosarum has been examined. roots, nodules and wild-type rhizobium culture medium contained very little cytokinin as indicated by bioassay. chemical ionisation gas chromatography-mass spectrometric analysis of the isopentenyladenine content of the culture medium from the rhizobium strains confirmed that the content of the wild-type was low (approx. 1 ng dm(-3)) but that it was increa ... | 1982 | 24271872 |
| bacteroid-encoded proteins are secreted into the peribacteroid space by rhizobium leguminosarum. | bacteroids of rhizobium leguminosarum in root nodules of pisum sativum are enclosed by a plant-derived peribacteriod membrane (pbm). the contents of the interstitial peribacteroid space (pbs) between bacteroid membrane and pbm were isolated by a controlled osmotic shock of pbm-enclosed bacteroids and analysed by two-dimensional gel electrophoresis. silver staining revealed approximately 40 pbs polypeptides. ex planta (35)s-methionine labeling of pbm-enclosed bacteroids revealed that about 90% of ... | 1988 | 24272260 |
| characterization of sym plasmids of rhizobium leguminosarum strains able to nodulate pisum sativum cv afghanistan. | rhizobium leguminosarum strains that can form nodules on pisum sativum cv. afghanistan have been reported as uncommon in europe, north america and africa [11, 12]. the organization of the nodulation regions of the symbiotic plasmids of five strains of r. leguminosarum originating from denmark [9], which can nodulate p. sativum cv. afghanistan, was compared with that of a turkish strain (tom [18]) by dna hybridizations. four of the five danish strains were found to be very similar to the turkish ... | 1988 | 24272399 |
| rhizobium leguminosarum genes required for expression and transfer of host specific nodulation. | the contributions of various nod genes from rhizobium leguminosarum biovar viceae to host-specific nodulation have been assessed by transferring specific genes and groups of genes to r. leguminosarum bv. trifolii and testing the levels of nodulation on pisum sativum (peas) and vicia hirsuta. many of the nod genes are important in determination of host-specificity; the node gene plays a key (but not essential) role and the efficiency of transfer of host specific nodulation increased with addition ... | 1989 | 24272714 |
| involvement of rhizobium leguminosarum nodulation genes in gene expression in pea root hairs. | the mrna population in pea root hairs was characterized by means of in vitro translation of total root hair rna followed by 2-dimensional gel electrophoresis of the translation products. root hairs contain several mrnas not detectable in total rna preparations from roots. most of these root hair-specific mrnas occur in elongating root hairs at higher levels than in mature root hairs. the expression of some genes in pea root hairs is typically affected by inoculation with rhizobium leguminosarum. ... | 1989 | 24272795 |
| acyl-homoserine lactone-based quorum sensing in the roseobacter clade: complex cell-to-cell communication controls multiple physiologies. | bacteria have been widely reported to use quorum sensing (qs) systems, which employ small diffusible metabolites to coordinate gene expression in a population density dependent manner. in proteobacteria, the most commonly described qs signaling molecules are n-acyl-homoserine lactones (ahls). recent studies suggest that members of the abundant marine roseobacter lineage possess ahl-based qs systems and are environmentally relevant models for relating qs to ecological success. as reviewed here, t ... | 2013 | 24273537 |
| cyanobase and rhizobase: databases of manually curated annotations for cyanobacterial and rhizobial genomes. | to understand newly sequenced genomes of closely related species, comprehensively curated reference genome databases are becoming increasingly important. we have extended cyanobase (http://genome.microbedb.jp/cyanobase), a genome database for cyanobacteria, and newly developed rhizobase (http://genome.microbedb.jp/rhizobase), a genome database for rhizobia, nitrogen-fixing bacteria associated with leguminous plants. both databases focus on the representation and reusability of reference genome a ... | 2013 | 24275496 |
| cyanobase and rhizobase: databases of manually curated annotations for cyanobacterial and rhizobial genomes. | to understand newly sequenced genomes of closely related species, comprehensively curated reference genome databases are becoming increasingly important. we have extended cyanobase (http://genome.microbedb.jp/cyanobase), a genome database for cyanobacteria, and newly developed rhizobase (http://genome.microbedb.jp/rhizobase), a genome database for rhizobia, nitrogen-fixing bacteria associated with leguminous plants. both databases focus on the representation and reusability of reference genome a ... | 2013 | 24275496 |
| promoters in the nodulation region of the rhizobium leguminosarum sym plasmid prl1ji. | a region of 16.8 kb of the sym(biosis) plasmid prl1ji of rhizobium leguminosarum, consisting of the established 9.7 kb nodulation region which confers nodulation ability on vicia hirsuta and a region of 7.1 kb which appeared to be necessary for nodulation on v. sativa and trifolium subterraneum, was subcloned as fragments of maximally 2.5 kb in a newly developed incq transcriptional fusion vector. the expression of these fragments was studied in rhizobium. one constitutive promoter, pr.nodd, and ... | 1987 | 24276795 |
| global transcriptional response to heat shock of the legume symbiont mesorhizobium loti maff303099 comprises extensive gene downregulation. | rhizobia, the bacterial legume symbionts able to fix atmospheric nitrogen inside root nodules, have to survive in varied environmental conditions. the aim of this study was to analyse the transcriptional response to heat shock of mesorhizobium loti maff303099, a rhizobium with a large multipartite genome of 7.6 mb that nodulates the model legume lotus japonicus. using microarray analysis, extensive transcriptomic changes were detected in response to heat shock: 30% of the protein-coding genes we ... | 2013 | 24277738 |
| global transcriptional response to heat shock of the legume symbiont mesorhizobium loti maff303099 comprises extensive gene downregulation. | rhizobia, the bacterial legume symbionts able to fix atmospheric nitrogen inside root nodules, have to survive in varied environmental conditions. the aim of this study was to analyse the transcriptional response to heat shock of mesorhizobium loti maff303099, a rhizobium with a large multipartite genome of 7.6 mb that nodulates the model legume lotus japonicus. using microarray analysis, extensive transcriptomic changes were detected in response to heat shock: 30% of the protein-coding genes we ... | 2013 | 24277738 |
| pathology-dependent effects linked to small heat shock proteins expression: an update. | small heat shock proteins (small hsps) are stress-induced molecular chaperones that act as holdases towards polypeptides that have lost their folding in stress conditions or consequently of mutations in their coding sequence. a cellular protection against the deleterious effects mediated by damaged proteins is thus provided to cells. these chaperones are also highly expressed in response to protein conformational and inflammatory diseases and cancer pathologies. through specific and reversible m ... | 2012 | 24278676 |
| non-native n-aroyl l-homoserine lactones are potent modulators of the quorum sensing receptor rpar in rhodopseudomonas palustris. | quorum sensing (qs) is a process by which bacteria use low-molecular-weight signaling molecules (or autoinducers) to assess their local population densities and alter gene expression levels at high cell numbers. many gram-negative bacteria use n-acyl l-homoserine lactones (ahls) with aliphatic acyl groups as signaling molecules for qs. however, bacteria that utilize ahls with aroyl acyl groups have been recently discovered; they include the metabolically versatile soil bacterium rhodopseudomonas ... | 2013 | 24281952 |
| non-native n-aroyl l-homoserine lactones are potent modulators of the quorum sensing receptor rpar in rhodopseudomonas palustris. | quorum sensing (qs) is a process by which bacteria use low-molecular-weight signaling molecules (or autoinducers) to assess their local population densities and alter gene expression levels at high cell numbers. many gram-negative bacteria use n-acyl l-homoserine lactones (ahls) with aliphatic acyl groups as signaling molecules for qs. however, bacteria that utilize ahls with aroyl acyl groups have been recently discovered; they include the metabolically versatile soil bacterium rhodopseudomonas ... | 2013 | 24281952 |
| the phosphopantetheinyl transferases: catalysis of a post-translational modification crucial for life. | covering: up to 2013. although holo-acyl carrier protein synthase, acps, a phosphopantetheinyl transferase (pptase), was characterized in the 1960s, it was not until the publication of the landmark paper by lambalot et al. in 1996 that pptases garnered wide-spread attention being classified as a distinct enzyme superfamily. in the past two decades an increasing number of papers have been published on pptases ranging from identification, characterization, structure determination, mutagenesis, inh ... | 2014 | 24292120 |
| genetic diversity of rhizobia isolated from nodules of the relic species vavilovia formosa (stev.) fed. | sixteen bacterial strains were isolated from root nodules of vavilovia formosa plants originated from the north ossetian state natural reserve (caucasus, russia). phylogenetic analysis of these strains was performed using partial 16s rrna gene and internally transcribed spacer (its) sequences. the results showed that the isolates belong to three families of root nodule bacteria. twelve of them were related to the genus rhizobium (family rhizobiaceae) but four strains can be most probably identif ... | 2014 | 24292378 |
| development of a pcr based marker system for easy identification and classification of aerobic endospore forming bacilli. | restriction fragment length analysis of 16s rrna gene of 52 different aerobic endospore forming bacilli (aefb) strains with haeiii enzyme has revealed the presence of a 460 bp long fragment in 50 aefb strains. blast analysis revealed that the fragment was 463 bp long and it was located at 3' end of 16s rrna gene. further specificity of this fragment for aefb strains was checked by pcr and in silico methods. in pcr based method a primer pair (463 f and 463r) specific to this fragment was designed ... | 2013 | 24298431 |
| solubility enhancement of α-naphthoflavone by synthesized hydroxypropyl cyclic-(1→2)-β-d-glucans (cyclosophoroases). | rhizobium leguminosarum produces unbranched cyclic β-1,2-glucans, cyclosophoraoses (cys). in the present study, cys were modified with hydroxypropyl groups via a one step chemical derivatization and the complexation ability and solubility enhancement of hydroxypropyl cyclosophoraoses (hp cys) with α-naphthoflavone (α-nf) were investigated. in the presence of hp cys, the aqueous solubility of α-nf greatly increased up to 257-fold. complex formation of hp cys and α-nf was confirmed by nuclear magn ... | 2014 | 24299833 |
| conserved-residue mutations in wzy affect o-antigen polymerization and wzz-mediated chain-length regulation in pseudomonas aeruginosa pao1. | o antigen (o-ag) in many bacteria is synthesized via the wzx/wzy-dependent pathway in which wzy polymerizes lipid-linked o-ag subunits to modal lengths regulated by wzz. characterization of 83 site-directed mutants of wzy from pseudomonas aeruginosa pao1 (wzypa) in topologically-mapped periplasmic (pl) and cytoplasmic loops (cl) verified the functional importance of pl3 and pl5, with the former shown to require overall cationic properties. essential arg residues in the rx10g motifs of pl3 and pl ... | 2013 | 24309320 |
| replicon-dependent differentiation of symbiosis-related genes in sinorhizobium strains nodulating glycine max. | in order to investigate the genetic differentiation of sinorhizobium strains nodulating glycine max and related microevolutionary mechanisms, three housekeeping genes (smc00019, trua, and thra) and 16 symbiosis-related genes on the chromosome (7 genes), psyma (6 genes), and psymb (3 genes) were analyzed. five distinct species were identified among the test strains by calculating the average nucleotide identity (ani) of smc00019-trua-thra: sinorhizobium fredii, sinorhizobium sojae, sinorhizobium ... | 2014 | 24317084 |
| metagenomics and novel gene discovery: promise and potential for novel therapeutics. | metagenomics provides a means of assessing the total genetic pool of all the microbes in a particular environment, in a culture-independent manner. it has revealed unprecedented diversity in microbial community composition, which is further reflected in the encoded functional diversity of the genomes, a large proportion of which consists of novel genes. herein, we review both sequence-based and functional metagenomic methods to uncover novel genes and outline some of the associated problems of e ... | 2013 | 24317337 |
| metagenomics and novel gene discovery: promise and potential for novel therapeutics. | metagenomics provides a means of assessing the total genetic pool of all the microbes in a particular environment, in a culture-independent manner. it has revealed unprecedented diversity in microbial community composition, which is further reflected in the encoded functional diversity of the genomes, a large proportion of which consists of novel genes. herein, we review both sequence-based and functional metagenomic methods to uncover novel genes and outline some of the associated problems of e ... | 2013 | 24317337 |
| mutation in the pssa gene involved in exopolysaccharide synthesis leads to several physiological and symbiotic defects in rhizobium leguminosarum bv. trifolii. | the symbiotic nitrogen-fixing bacterium rhizobium leguminosarum bv. trifolii 24.2 secretes large amounts of acidic exopolysaccharide (eps), which plays a crucial role in establishment of effective symbiosis with clover. the biosynthesis of this heteropolymer is conducted by a multi-enzymatic complex located in the bacterial inner membrane. pssa protein, responsible for the addition of glucose-1-phosphate to a polyprenyl phosphate carrier, is involved in the first step of eps synthesis. in this w ... | 2013 | 24317432 |
| engineering rhizobial bioinoculants: a strategy to improve iron nutrition. | under field conditions, inoculated rhizobial strains are at a survival disadvantage as compared to indigenous strains. in order to out-compete native rhizobia it is not only important to develop strong nodulation efficiency but also increase their competence in the soil and rhizosphere. competitive survival of the inoculated strain may be improved by employing strain selection and by genetic engineering of superior nitrogen fixing strains. iron sufficiency is an important factor determining the ... | 2013 | 24319357 |
| a view to a kill: the bacterial type vi secretion system. | the bacterial type vi secretion system (t6ss) is an organelle that is structurally and mechanistically analogous to an intracellular membrane-attached contractile phage tail. recent studies determined that a rapid conformational change in the structure of a sheath protein complex propels t6ss spike and tube components along with antibacterial and antieukaryotic effectors out of predatory t6ss(+) cells and into prey cells. the contracted organelle is then recycled in an atp-dependent process. t6s ... | 2013 | 24332978 |
| a view to a kill: the bacterial type vi secretion system. | the bacterial type vi secretion system (t6ss) is an organelle that is structurally and mechanistically analogous to an intracellular membrane-attached contractile phage tail. recent studies determined that a rapid conformational change in the structure of a sheath protein complex propels t6ss spike and tube components along with antibacterial and antieukaryotic effectors out of predatory t6ss(+) cells and into prey cells. the contracted organelle is then recycled in an atp-dependent process. t6s ... | 2013 | 24332978 |
| relationship between ni(ii) and zn(ii) coordination and nucleotide binding by the helicobacter pylori [nife]-hydrogenase and urease maturation factor hypb. | the pathogen helicobacter pylori requires two nickel-containing enzymes, urease and [nife]-hydrogenase, for efficient colonization of the human gastric mucosa. these enzymes possess complex metallocenters that are assembled by teams of proteins in multistep pathways. one essential accessory protein is the gtpase hypb, which is required for ni(ii) delivery to [nife]-hydrogenase and participates in urease maturation. ni(ii) or zn(ii) binding to a site embedded in the gtpase domain of hypb modulate ... | 2013 | 24338018 |
| relationship between ni(ii) and zn(ii) coordination and nucleotide binding by the helicobacter pylori [nife]-hydrogenase and urease maturation factor hypb. | the pathogen helicobacter pylori requires two nickel-containing enzymes, urease and [nife]-hydrogenase, for efficient colonization of the human gastric mucosa. these enzymes possess complex metallocenters that are assembled by teams of proteins in multistep pathways. one essential accessory protein is the gtpase hypb, which is required for ni(ii) delivery to [nife]-hydrogenase and participates in urease maturation. ni(ii) or zn(ii) binding to a site embedded in the gtpase domain of hypb modulate ... | 2013 | 24338018 |
| 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 |
| a nodule-specific lipid transfer protein ase246 participates in transport of plant-synthesized lipids to symbiosome membrane and is essential for nodule organogenesis in chinese milk vetch. | rhizobia in legume root nodules fix nitrogen in symbiosomes, organelle-like structures in which a membrane from the host plant surrounds the symbiotic bacteria. however, the components that transport plant-synthesized lipids to the symbiosome membrane remain unknown. this study identified and functionally characterized the chinese milk vetch (astragalus sinicus) lipid transfer protein ase246, which is specifically expressed in nodules. it was found that ase246 can bind lipids in vitro. more impo ... | 2013 | 24367021 |
| a nodule-specific lipid transfer protein ase246 participates in transport of plant-synthesized lipids to symbiosome membrane and is essential for nodule organogenesis in chinese milk vetch. | rhizobia in legume root nodules fix nitrogen in symbiosomes, organelle-like structures in which a membrane from the host plant surrounds the symbiotic bacteria. however, the components that transport plant-synthesized lipids to the symbiosome membrane remain unknown. this study identified and functionally characterized the chinese milk vetch (astragalus sinicus) lipid transfer protein ase246, which is specifically expressed in nodules. it was found that ase246 can bind lipids in vitro. more impo ... | 2013 | 24367021 |
| iron homeostasis in the rhodobacter genus. | metals are utilized for a variety of critical cellular functions and are essential for survival. however cells are faced with the conundrum of needing metals coupled with e fact that some metals, iron in particular are toxic if present in excess. maintaining metal homeostasis is therefore of critical importance to cells. in this review we have systematically analyzed sequenced genomes of three members of the rhodobacter genus, r. capsulatus sb1003, r. sphaeroides 2.4.1 and r. ferroxidans sw2 to ... | 2013 | 24382933 |
| type vi secretion system effectors: poisons with a purpose. | the type vi secretion system (t6ss) mediates interactions between a broad range of gram-negative bacterial species. recent studies have led to a substantial increase in the number of characterized t6ss effector proteins and a more complete and nuanced view of the adaptive importance of the system. although the t6ss is most often implicated in antagonism, in this review, we consider the case for its involvement in both antagonistic and non-antagonistic behaviours. clarifying the roles that type v ... | 2014 | 24384601 |
| comparative genomics and functional analysis of rhamnose catabolic pathways and regulons in bacteria. | l-rhamnose (l-rha) is a deoxy-hexose sugar commonly found in nature. l-rha catabolic pathways were previously characterized in various bacteria including escherichia coli. nevertheless, homology searches failed to recognize all the genes for the complete l-rha utilization pathways in diverse microbial species involved in biomass decomposition. moreover, the regulatory mechanisms of l-rha catabolism have remained unclear in most species. a comparative genomics approach was used to reconstruct the ... | 2013 | 24391637 |
| 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. we also investigated the effects on swarming when rhizobium is exposed to extracts from an ancestor to vascular plants, the model bryophyte physcomitrella patens. lentil and faba bean seed exudates enhanced and inhibited swarming motility, respectively, wherea ... | 2014 | 24392922 |
| characterization of rhizobium grahamii extrachromosomal replicons and their transfer among rhizobia. | rhizobium grahamii belongs to a new phylogenetic group of rhizobia together with rhizobium mesoamericanum and other species. r. grahamii has a broad-host-range that includes leucaena leucocephala and phaseolus vulgaris, although it is a poor competitor for p. vulgaris nodulation in the presence of rhizobium etli or rhizobium phaseoli strains. this work analyzed the genome sequence and transfer properties of r. grahamii plasmids. | 2014 | 24397311 |
| phototropism: some history, some puzzles, and a look ahead. | 2014 | 24399823 | |
| rhizobium leguminosarum inoculation decreases damage to faba bean (vicia faba) caused by broad bean mottle bromovirus and bean yellow mosaic potyvirus. | faba bean (vicia faba) plants were inoculated with rhizobia and then their sap was infected with broad bean mottle bromovirus (bbmv) or bean yellow mosaic potyvirus (bymv) in a field experiment. both viral infections significantly decreased shoot and root dry weight, number of nodules, nodule dry weight, numbers of flowers and pods/plant, total plant n, grain yield and n2 fixation. however, inoculation withrhizobium leguminosarum significantly increased all these parameters, both in healthy and ... | 1995 | 24414508 |
| plant-associated symbiotic burkholderia species lack hallmark strategies required in mammalian pathogenesis. | burkholderia is a diverse and dynamic genus, containing pathogenic species as well as species that form complex interactions with plants. pathogenic strains, such as b. pseudomallei and b. mallei, can cause serious disease in mammals, while other burkholderia strains are opportunistic pathogens, infecting humans or animals with a compromised immune system. although some of the opportunistic burkholderia pathogens are known to promote plant growth and even fix nitrogen, the risk of infection to i ... | 2014 | 24416172 |
| comparative genomics of cultured and uncultured strains suggests genes essential for free-living growth of liberibacter. | the full genomes of two uncultured plant pathogenic liberibacter, ca. liberibacter asiaticus and ca. liberibacter solanacearum, are publicly available. recently, the larger genome of a closely related cultured strain, liberibacter crescens bt-1, was described. to gain insights into our current inability to culture most liberibacter, a comparative genomics analysis was done based on the rast, kegg, and manual annotations of these three organisms. in addition, pathogenicity genes were examined in ... | 2014 | 24416233 |
| assessment of faba bean (vicia faba) response to inoculation with rhizobium leguminosarum in clay loam nile delta soil. | a field experiment was conducted to assess the response to inoculation with rhizobia in a clay loam soil of the nile delta using faba bean (vicia faba) for two successive winter seasons (1985/6 and 1986/7). three selected strains of rhizobium leguminosarum, tal 634, nrc 65 and tal 1400, were used singly or in combination as peat-based inocula in 1985/6 winter season. strain tal 1400 was replaced by strain f9 in the 1986/7 winter season. a significant seed yield response was obtained only with st ... | 1991 | 24424931 |
| performance of chickpea, lentil and lupin nodulated with indigenous or inoculated rhizobia micropartners under nitrogen, boron, cobalt and molybdenum fertilization schedules. | chickpea (cicer arietinum), lentil (lens esculenta) and lupin (lupinus albus) responded to inoculation with their respective symbiotants:rhizobium loti, rhizobium leguminosarum biovarviceae andbradyrhizobium sp. (lupinus) alone or with (nh4)2so4 at 30 ppm n. soil application of na2moo4.2h2o at 3 ppm mo, cocl2.6h2o at 2 ppm co(2+) or na2b4o7.10h2o at 1 ppm b with 0 and 30 ppm n increased nodule weight and plant dry weight and n-content 60 days after sowing and seed yield, seed size and the n and ... | 1992 | 24425609 |
| molecular cloning, expression of mind gene from lactobacillus acidophilus vtcc-b-871 and analyses to identify lactobacillus rhamnosus pn04 from vietnam hottuynia cordata thunb. | the mind gene encoding an inhibitor cell division mind homolog from lactobacillus acidophilus vtcc-b-871 was cloned. we showed that there were 97 % homology between mind genes of l. acidophilus vtcc-b-871 and lactobacillus rhamnosus gg and lactobacillus rhamnosus lc705. based on the analysis of the dna sequence data from the l. rhamnosus genome project and sequenced mind gene of l. acidophilus vtcc-b-871, a pair of primers was designed to identified the different mind genes from l. acidophilus a ... | 2013 | 24426140 |
| proline biosynthesizing enzymes (glutamate 5-kinase and pyrroline-5-carboxylate reductase) from a model cyanobacterium for desiccation tolerance. | drought is the most important abiotic stress, challenging sustainable agriculture globally. for desiccation being the multigenic trait, a combination of identified genes from the appropriate organism may render crop tolerant to the water stress. among the compatible solutes, proline plays multifaceted role in counteracting such stress. the genes encoding proline biosynthesizing enzymes, glutamate 5-kinase (g5k), and pyrroline-5-carboxylate reductase (p5cr) from the low-desiccation-tolerant cyano ... | 2013 | 24431521 |
| genes conferring copper resistance in sinorhizobium meliloti ccnwsx0020 also promote the growth of medicago lupulina in copper-contaminated soil. | sinorhizobium meliloti ccnwsx0020, isolated from root nodules of medicago lupulina growing in gold mine tailings in the northwest of china, displayed both copper resistance and growth promotion of leguminous plants in copper-contaminated soil. nevertheless, the genetic and biochemical mechanisms responsible for copper resistance in s. meliloti ccnwsx0020 remained uncharacterized. to investigate genes involved in copper resistance, an s. meliloti ccnwsx0020 tn5 insertion library of 14,000 mutants ... | 2014 | 24441157 |
| a signaling pathway involving the diguanylate cyclase celr and the response regulator divk controls cellulose synthesis in agrobacterium tumefaciens. | the production of cellulose fibrils is involved in the attachment of agrobacterium tumefaciens to its plant host. consistent with previous studies, we reported recently that a putative diguanylate cyclase, celr, is required for synthesis of this polymer in a. tumefaciens. in this study, the effects of celr and other components of the regulatory pathway of cellulose production were explored. mutational analysis of celr demonstrated that the cyclase requires the catalytic ggeef motif, as well as t ... | 2014 | 24443526 |
| rubredoxin-related maturation factor guarantees metal cofactor integrity during aerobic biosynthesis of membrane-bound [nife] hydrogenase. | the membrane-bound [nife] hydrogenase (mbh) supports growth of ralstonia eutropha h16 with h2 as the sole energy source. the enzyme undergoes a complex biosynthesis process that proceeds during cell growth even at ambient o2 levels and involves 14 specific maturation proteins. one of these is a rubredoxin-like protein, which is essential for biosynthesis of active mbh at high oxygen concentrations but dispensable under microaerobic growth conditions. to obtain insights into the function of hoxr, ... | 2014 | 24448806 |
| the genome sequence of the fungal pathogen fusarium virguliforme that causes sudden death syndrome in soybean. | fusarium virguliforme causes sudden death syndrome (sds) of soybean, a disease of serious concern throughout most of the soybean producing regions of the world. despite the global importance, little is known about the pathogenesis mechanisms of f. virguliforme. thus, we applied next-generation dna sequencing to reveal the draft f. virguliforme genome sequence and identified putative pathogenicity genes to facilitate discovering the mechanisms used by the pathogen to cause this disease. | 2014 | 24454689 |
| the moxr atpase rava and its cofactor viaa interact with the nadh:ubiquinone oxidoreductase i in escherichia coli. | moxr atpases are widespread throughout bacteria and archaea. the experimental evidence to date suggests that these proteins have chaperone-like roles in facilitating the maturation of dedicated protein complexes that are functionally diverse. in escherichia coli, the moxr atpase rava and its putative cofactor viaa are found to exist in early stationary-phase cells at 37 °c at low levels of about 350 and 90 molecules per cell, respectively. both proteins are predominantly localized to the cytopla ... | 2014 | 24454883 |
| a link between arabinose utilization and oxalotrophy in bradyrhizobium japonicum. | rhizobia have a versatile catabolism that allows them to compete successfully with other microorganisms for nutrients in the soil and in the rhizosphere of their respective host plants. in this study, bradyrhizobium japonicum usda 110 was found to be able to utilize oxalate as the sole carbon source. a proteome analysis of cells grown in minimal medium containing arabinose suggested that oxalate oxidation extends the arabinose degradation branch via glycolaldehyde. a mutant of the key pathway ge ... | 2014 | 24463964 |
| identification and characterization of a second quorum-sensing system in agrobacterium tumefaciens a6. | quorum sensing (qs) is a widespread mechanism of bacterial communication in which individual cells produce and respond to small chemical signals. in agrobacterium tumefaciens, an acylhomoserine lactone-dependent qs mechanism is known to regulate the replication and conjugation of the tumor-inducing (ti) plasmid. most of the qs regulatory proteins are encoded within the ti plasmid. among them, trai is the luxi-type enzyme synthesizing the qs signal n-3-oxooctanoyl-l-homoserine lactone (3oc8hsl), ... | 2014 | 24464459 |
| the soil bacterial communities of south african fynbos riparian ecosystems invaded by australian acacia species. | riparian ecosystem along rivers and streams are characterised by lateral and longitudinal ecological gradients and, as a result, harbour unique biodiversity. riparian ecosystems in the fynbos of the western cape, south africa, are characterised by seasonal dynamics, with summer droughts followed by high flows during winter. the unique hydrology and geomorphology of riparian ecosystems play an important role in shaping these ecosystems. the riparian vegetation in the western cape has, however, la ... | 2014 | 24475145 |
| radical s-adenosylmethionine enzymes. | 2014 | 24476342 | |
| abscisic acid inhibition of root nodule initiation in pisum sativum. | the effect of exogenous abscisic acid (aba) on root nodule formation in pisum sativum cv. alaska was examined. aba supplied to the roots at 1.9×10(-6)m reduced the number of nodules/plant 61% without affecting root or shoot growth. the first noticeable inhibition of nodulation occurred at 3.8×10(-7)m aba. aba at a concentration of 1.9×10(-6)m inhibited neither root hair formation nor infection of root hairs by rhizobium leguminosarum. similar numbers of infection threads penetrated the cortex in ... | 1971 | 24488191 |
| rnase e affects the expression of the acyl-homoserine lactone synthase gene sini in sinorhizobium meliloti. | quorum sensing of sinorhizobium meliloti relies on n-acyl-homoserine lactones (ahls) as autoinducers. ahl production increases at high population density, and this depends on the ahl synthase sini and two transcriptional regulators, sinr and expr. our study demonstrates that ectopic expression of the gene rne, coding for rnase e, an endoribonuclease that is probably essential for growth, prevents the accumulation of ahls at detectable levels. the ectopic rne expression led to a higher level of r ... | 2014 | 24488310 |
| the kiwifruit emerging pathogen pseudomonas syringae pv. actinidiae does not produce ahls but possesses three luxr solos. | pseudomonas syringae pv. actinidiae (psa) is an emerging phytopathogen causing bacterial canker disease in kiwifruit plants worldwide. quorum sensing (qs) gene regulation plays important roles in many different bacterial plant pathogens. in this study we analyzed the presence and possible role of n-acyl homoserine lactone (ahl) quorum sensing in psa. it was established that psa does not produce ahls and that a typical complete luxi/r qs system is absent in psa strains. psa however possesses thre ... | 2014 | 24498215 |
| non-additive costs and interactions alter the competitive dynamics of co-occurring ecologically distinct plasmids. | plasmids play an important role in shaping bacterial evolution and adaptation to heterogeneous environments. as modular genetic elements that are often conjugative, the selective pressures that act on plasmid-borne genes are distinct from those that act on the chromosome. many bacteria are co-infected by multiple plasmids that impart niche-specific phenotypes. thus, in addition to host-plasmid dynamics, interactions between co-infecting plasmids are likely to be important drivers of plasmid popu ... | 2014 | 24500159 |
| global analysis of cell cycle gene expression of the legume symbiont sinorhizobium meliloti. | in α-proteobacteria, strict regulation of cell cycle progression is necessary for the specific cellular differentiation required for adaptation to diverse environmental niches. the symbiotic lifestyle of sinorhizobium meliloti requires a drastic cellular differentiation that includes genome amplification. to achieve polyploidy, the s. meliloti cell cycle program must be altered to uncouple dna replication from cell division. in the α-proteobacterium caulobacter crescentus, cell cycle-regulated t ... | 2014 | 24501121 |
| expr coordinates the expression of symbiotically important, bundle-forming flp pili with quorum sensing in sinorhizobium meliloti. | type ivb pili in enteropathogenic bacteria function as a host colonization factor by mediating tight adherence to host cells, but their role in bacterium-plant symbiosis is currently unknown. the genome of the symbiotic soil bacterium sinorhizobium meliloti contains two clusters encoding proteins for type ivb pili of the flp (fimbrial low-molecular-weight protein) subfamily. to establish the role of flp pili in the symbiotic interaction of s. meliloti and its host, medicago sativa, we deleted pi ... | 2014 | 24509921 |
| the ctra phosphorelay integrates differentiation and communication in the marine alphaproteobacterium dinoroseobacter shibae. | dinoroseobacter shibae, a member of the roseobacter clade abundant in marine environments, maintains morphological heterogeneity throughout growth, with small cells dividing by binary fission and large cells dividing by budding from one or both cell poles. this morphological heterogeneity is lost if the quorum sensing (qs) system is silenced, concurrent with a decreased expression of the ctra phosphorelay, a regulatory system conserved in alphaproteobacteria and the master regulator of the caulo ... | 2014 | 24524855 |
| identification of rhizobial strains nodulating egyptian grain legumes. | fifty four bacterial strains were isolated from root nodules of the grain legumes cicer arietinum, lens esculentus, phaseolus vulgaris, pisum sativum, and vicia faba grown in cultivated lands of beni-suef governorate (egypt). repetitive extragenic palindromic (rep)-polymerase chain reaction (pcr) clustered the strains into 15 rep-pcr groups. the nearly complete sequence of the 16s rrna gene from a representative strain of each rep-pcr pattern showed that the strains were closely related to membe ... | 2013 | 24568031 |
| molecular phylogenetics before sequences: oligonucleotide catalogs as k-mer spectra. | from 1971 to 1985, carl woese and colleagues generated oligonucleotide catalogs of 16s/18s rrnas from more than 400 organisms. using these incomplete and imperfect data, carl and his colleagues developed unprecedented insights into the structure, function, and evolution of the large rna components of the translational apparatus. they recognized a third domain of life, revealed the phylogenetic backbone of bacteria (and its limitations), delineated taxa, and explored the tempo and mode of microbi ... | 2014 | 24572375 |
| genotypic and symbiotic diversity of rhizobium populations associated with cultivated lentil and pea in sub-humid and semi-arid regions of eastern algeria. | the genetic structure of rhizobia nodulating pea and lentil in algeria, northern africa was determined. a total of 237 isolates were obtained from root nodules collected on lentil (lens culinaris), proteaginous and forage pea (pisum sativum) growing in two eco-climatic zones, sub-humid and semi-arid, in eastern algeria. they were characterised by pcr-restriction fragment length polymorphism (rflp) of the 16s-23s rrna intergenic region (igs), and the nodd-f symbiotic region. the combination of th ... | 2014 | 24582507 |
| utilization of glyphosate as phosphate source: biochemistry and genetics of bacterial carbon-phosphorus lyase. | after several decades of use of glyphosate, the active ingredient in weed killers such as roundup, in fields, forests, and gardens, the biochemical pathway of transformation of glyphosate phosphorus to a useful phosphorus source for microorganisms has been disclosed. glyphosate is a member of a large group of chemicals, phosphonic acids or phosphonates, which are characterized by a carbon-phosphorus bond. this is in contrast to the general phosphorus compounds utilized and metabolized by microor ... | 2014 | 24600043 |
| efficient synthesis of eriodictyol from l-tyrosine in escherichia coli. | the health benefits of flavonoids for humans are increasingly attracting attention. because the extraction of high-purity flavonoids from plants presents a major obstacle, interest has emerged in biosynthesizing them using microbial hosts. eriodictyol is a flavonoid with anti-inflammatory and antioxidant activities. its efficient synthesis has been hampered by two factors: the poor expression of cytochrome p450 and the low intracellular malonyl coenzyme a (malonyl-coa) concentration in escherich ... | 2014 | 24610848 |
| the growth of steroidobacter agariperforans sp. nov., a novel agar-degrading bacterium isolated from soil, is enhanced by the diffusible metabolites produced by bacteria belonging to rhizobiales. | an agar-degrading bacterium was isolated from soil collected in a vegetable cropping field. the growth of this isolate was enhanced by supplying culture supernatants of bacteria belonging to the order rhizobiales. phylogenetic analysis based on 16s rrna gene sequences indicated the novel bacterium, strain ka5-b(t), belonged to the genus steroidobacter in gammaproteobacteria, but differed from its closest relative, steroidobacter denitrificans fs(t), at the species level with 96.5% similarity. st ... | 2014 | 24621511 |
| responses to elevated c-di-gmp levels in mutualistic and pathogenic plant-interacting bacteria. | despite a recent burst of research, knowledge on c-di-gmp signaling pathways remains largely fragmentary and molecular mechanisms of regulation and even c-di-gmp targets are yet unknown for most bacteria. besides genomics or bioinformatics, accompanying alternative approaches are necessary to reveal c-di-gmp regulation in bacteria with complex lifestyles. we have approached this study by artificially altering the c-di-gmp economy of diverse pathogenic and mutualistic plant-interacting bacteria a ... | 2014 | 24626229 |
| fha interaction with phosphothreonine of tssl activates type vi secretion in agrobacterium tumefaciens. | the type vi secretion system (t6ss) is a widespread protein secretion system found in many gram-negative bacteria. t6sss are highly regulated by various regulatory systems at multiple levels, including post-translational regulation via threonine (thr) phosphorylation. the ser/thr protein kinase ppka is responsible for this thr phosphorylation regulation, and the forkhead-associated (fha) domain-containing fha-family protein is the sole t6ss phosphorylation substrate identified to date. here we d ... | 2014 | 24626341 |
| comparison of inhibition of n2 fixation and ureide accumulation under water deficit in four common bean genotypes of contrasting drought tolerance. | drought is the principal constraint on world production of legume crops. there is considerable variability among genotypes in sensitivity of nitrogen fixation to drought, which has been related to accumulation of ureides in soybean. the aim of this study was to search for genotypic differences in drought sensitivity and ureide accumulation in common bean (phaseolus vulgaris) germplasm that may be useful in the improvement of tolerance to water deficit in common bean. | 2014 | 24638821 |
| differential control of bradyrhizobium japonicum iron stimulon genes through variable affinity of the iron response regulator (irr) for target gene promoters and selective loss of activator function. | bradyrhizobium japonicum irr is a conditionally stable transcriptional activator and repressor that accumulates in cells under iron-limited, manganese-replete conditions, but degrades in a haem-dependent manner under high iron conditions, manganese limitation or upon exposure to h2 o2 . here, we identified irr-regulated genes that were relatively unresponsive to factors that promote irr degradation. the promoters of those genes bound irr with at least 200-fold greater affinity than promoters of ... | 2014 | 24646221 |
| comparative genomic analysis of n2-fixing and non-n2-fixing paenibacillus spp.: organization, evolution and expression of the nitrogen fixation genes. | we provide here a comparative genome analysis of 31 strains within the genus paenibacillus including 11 new genomic sequences of n2-fixing strains. the heterogeneity of the 31 genomes (15 n2-fixing and 16 non-n2-fixing paenibacillus strains) was reflected in the large size of the shell genome, which makes up approximately 65.2% of the genes in pan genome. large numbers of transposable elements might be related to the heterogeneity. we discovered that a minimal and compact nif cluster comprising ... | 2014 | 24651173 |
| sinorhizobium meliloti chemoreceptor mcpu mediates chemotaxis toward host plant exudates through direct proline sensing. | bacterial chemotaxis is an important attribute that aids in establishing symbiosis between rhizobia and their legume hosts. plant roots and seeds exude a spectrum of molecules into the soil to attract their bacterial symbionts. the alfalfa symbiont sinorhizobium meliloti possesses eight chemoreceptors to sense its environment and mediate chemotaxis toward its host. the methyl accepting chemotaxis protein mcpu is one of the more abundant s. meliloti chemoreceptors and an important sensor for the ... | 2014 | 24657863 |
| engineering microbes for plant polyketide biosynthesis. | polyketides are an important group of secondary metabolites, many of which have important industrial applications in the food and pharmaceutical industries. polyketides are synthesized from one of three classes of enzymes differentiated by their biochemical features and product structure: type i, type ii or type iii polyketide synthases (pkss). plant type iii pks enzymes, which will be the main focus of this review, are relatively small homodimeric proteins that catalyze iterative decarboxylativ ... | 2012 | 24688680 |
| engineering microbes for plant polyketide biosynthesis. | polyketides are an important group of secondary metabolites, many of which have important industrial applications in the food and pharmaceutical industries. polyketides are synthesized from one of three classes of enzymes differentiated by their biochemical features and product structure: type i, type ii or type iii polyketide synthases (pkss). plant type iii pks enzymes, which will be the main focus of this review, are relatively small homodimeric proteins that catalyze iterative decarboxylativ ... | 2012 | 24688680 |
| the potential roles of strigolactones and brassinosteroids in the autoregulation of nodulation pathway. | the number of nodules formed on a legume root system is under the strict genetic control of the autoregulation of nodulation (aon) pathway. plant hormones are thought to play a role in aon; however, the involvement of two hormones recently described as having a largely positive role in nodulation, strigolactones and brassinosteroids, has not been examined in the aon process. | 2014 | 24694828 |
| insights into protein allostery in the csor/rcnr family of transcriptional repressors. | csor/rcnr transcriptional repressors adopt a disc-shaped, all α-helical dimer of dimers tetrameric architecture, with a four-helix bundle the key structural feature of the dimer. individual members of this large family of repressors coordinate cu(i) or ni(ii)/co(ii) or perform cysteine sulfur chemistry in mitigating the effects of metal or metabolite toxicity, respectively. here we highlight recent insights into the functional diversity of this fascinating family of repressors. | 2013 | 24695963 |
| insights into protein allostery in the csor/rcnr family of transcriptional repressors. | csor/rcnr transcriptional repressors adopt a disc-shaped, all α-helical dimer of dimers tetrameric architecture, with a four-helix bundle the key structural feature of the dimer. individual members of this large family of repressors coordinate cu(i) or ni(ii)/co(ii) or perform cysteine sulfur chemistry in mitigating the effects of metal or metabolite toxicity, respectively. here we highlight recent insights into the functional diversity of this fascinating family of repressors. | 2013 | 24695963 |
| the genetics of symbiotic nitrogen fixation: comparative genomics of 14 rhizobia strains by resolution of protein clusters. | the symbiotic relationship between legumes and nitrogen fixing bacteria is critical for agriculture, as it may have profound impacts on lowering costs for farmers, on land sustainability, on soil quality, and on mitigation of greenhouse gas emissions. however, despite the importance of the symbioses to the global nitrogen cycling balance, very few rhizobial genomes have been sequenced so far, although there are some ongoing efforts in sequencing elite strains. in this study, the genomes of fourt ... | 2012 | 24704847 |
| genome sequence of azospirillum brasilense cbg497 and comparative analyses of azospirillum core and accessory genomes provide insight into niche adaptation. | bacteria of the genus azospirillum colonize roots of important cereals and grasses, and promote plant growth by several mechanisms, notably phytohormone synthesis. the genomes of several azospirillum strains belonging to different species, isolated from various host plants and locations, were recently sequenced and published. in this study, an additional genome of an a. brasilense strain, isolated from maize grown on an alkaline soil in the northeast of mexico, strain cbg497, was obtained. compa ... | 2012 | 24705077 |
| annotation of protein domains reveals remarkable conservation in the functional make up of proteomes across superkingdoms. | the functional repertoire of a cell is largely embodied in its proteome, the collection of proteins encoded in the genome of an organism. the molecular functions of proteins are the direct consequence of their structure and structure can be inferred from sequence using hidden markov models of structural recognition. here we analyze the functional annotation of protein domain structures in almost a thousand sequenced genomes, exploring the functional and structural diversity of proteomes. we find ... | 2011 | 24710297 |
| plant-bacteria association and symbiosis: are there common genomic traits in alphaproteobacteria? | alphaproteobacteria show a great versatility in adapting to a broad range of environments and lifestyles, with the association between bacteria and plants as one of the most intriguing, spanning from relatively unspecific nonsymbiotic association (as rhizospheric or endophytic strains) to the highly species-specific interaction of rhizobia. to shed some light on possible common genetic features in such a heterogeneous set of plant associations, the genomes of 92 alphaproteobacteria strains were ... | 2011 | 24710303 |
| phenotypic characterization of astragalus glycyphyllos symbionts and their phylogeny based on the 16s rdna sequences and rflp of 16s rrna gene. | in this study, the nitrogen fixing astragalus glycyphyllos symbionts were characterized by phenotypic properties, restriction fragment length polymorphism (rflp), and sequences of 16s rdna. the generation time of a. glycyphyllos rhizobia in yeast extract mannitol medium was in the range 4-6 h. the studied isolates exhibited a low resistance to antibiotics, a moderate tolerance to nacl, assimilated di- and trisaccharides, and produced acid in medium containing mannitol as a sole carbon source. in ... | 2014 | 24710996 |
| membrane lipids in agrobacterium tumefaciens: biosynthetic pathways and importance for pathogenesis. | many cellular processes critically depend on the membrane composition. in this review, we focus on the biosynthesis and physiological roles of membrane lipids in the plant pathogen agrobacterium tumefaciens. the major components of a. tumefaciens membranes are the phospholipids (pls), phosphatidylethanolamine (pe), phosphatidylglycerol, phosphatidylcholine (pc) and cardiolipin, and ornithine lipids (ols). under phosphate-limited conditions, the membrane composition shifts to phosphate-free lipid ... | 2014 | 24723930 |
| proteomic comparison of ralstonia solanacearum strains reveals temperature dependent virulence factors. | ralstonia solanacearum, the causal agent of bacterial wilt, is a genetically diverse bacterial plant pathogen present in tropical and subtropical regions of the world that infects more than 200 plant species, including economically important solanaceous crops. most strains of r. solanacearum are only pathogenic at temperatures between 25 to 30°c with strains that can cause disease below 20°c considered a threat to agriculture in temperate areas. identifying key molecular factors that distinguish ... | 2014 | 24725348 |
| genomic analysis of cyclic-di-gmp-related genes in rhizobial type strains and functional analysis in rhizobium etli. | rhizobia are soil bacteria that can fix nitrogen in symbiosis with leguminous plants or exist free living in the rhizosphere. crucial to their complex lifestyle is the ability to sense and respond to diverse environmental stimuli, requiring elaborate signaling pathways. in the majority of bacteria, the nucleotide-based second messenger cyclic diguanosine monophosphate (c-di-gmp) is involved in signal transduction. surprisingly, little is known about the importance of c-di-gmp signaling in rhizob ... | 2014 | 24728599 |
| cloning and characterization of a galactitol 2-dehydrogenase from rhizobium legumenosarum and its application in d-tagatose production. | galactitol 2-dehydrogenase (gdh) belongs to the protein subfamily of short-chain dehydrogenases/reductases and can be used to produce optically pure building blocks and for the bioconversion of bioactive compounds. an nad(+)-dependent gdh from rhizobium leguminosarum bv. viciae 3841 (rlgdh) was cloned and overexpressed in escherichia coli. the rlgdh protein was purified as an active soluble form using his-tag affinity chromatography. the molecular mass of the purified enzyme was estimated to be ... | 2014 | 24731824 |
| assessment of core and accessory genetic variation in rhizobium leguminosarum symbiovar trifolii strains from diverse locations and host plants using pcr-based methods. | the nitrogen-fixing symbiosis between rhizobium leguminosarum and host legumes is recognized as a key part of sustainable agriculture. a culture collection containing rhizobia isolated from legumes of economic importance in the uk and worldwide, maintained at rothamsted research for many years, provided material for this study. we aimed to develop and validate efficient molecular diagnostics to investigate whether the host plant or geographical location had a greater influence on the genetic div ... | 2014 | 24739023 |
| a proteomic approach reveals new actors of nodule response to drought in split-root grown pea plants. | drought is considered the more harmful abiotic stress resulting in crops yield loss. legumes in symbiosis with rhizobia are able to fix atmospheric nitrogen. biological nitrogen fixation (snf) is a very sensitive process to drought and limits legumes agricultural productivity. several factors are known to regulate snf including oxygen availability to bacteroids, carbon and nitrogen metabolisms; but the signaling pathways leading to snf inhibition are largely unknown. in this work, we have perfor ... | 2014 | 24754352 |
| the transcriptional activator ldtr from 'candidatus liberibacter asiaticus' mediates osmotic stress tolerance. | the causal agent of huanglongbing disease, 'candidatus liberibacter asiaticus', is a non-culturable, gram negative, phloem-limited α-proteobacterium. current methods to control the spread of this disease are still limited to the removal and destruction of infected trees. in this study, we identified and characterized a regulon from 'ca. l. asiaticus' involved in cell wall remodeling, that contains a member of the marr family of transcriptional regulators (ldtr), and a predicted l,d-transpeptidas ... | 2014 | 24763829 |
| discovery of a sar11 growth requirement for thiamin's pyrimidine precursor and its distribution in the sargasso sea. | vitamin traffic, the production of organic growth factors by some microbial community members and their use by other taxa, is being scrutinized as a potential explanation for the variation and highly connected behavior observed in ocean plankton by community network analysis. thiamin (vitamin b1), a cofactor in many essential biochemical reactions that modify carbon-carbon bonds of organic compounds, is distributed in complex patterns at subpicomolar concentrations in the marine surface layer (0 ... | 2014 | 24781899 |
| a bacterial iron exporter for maintenance of iron homeostasis. | nutritional iron acquisition by bacteria is well described, but almost nothing is known about bacterial iron export even though it is likely to be an important homeostatic mechanism. here, we show that bradyrhizobium japonicum mbfa (blr7895) is an inner membrane protein expressed in cells specifically under high iron conditions. mbfa contains an n-terminal ferritin-like domain (fld) and a c-terminal domain homologous to the eukaryotic vacuolar membrane fe(2+)/mn(2+) transporter ccc1. an mbfa del ... | 2014 | 24782310 |
| symbiotic activity of pea (pisum sativum) after application of nod factors under field conditions. | growth and symbiotic activity of legumes are mediated by nod factors (lco, lipo-chitooligosaccharides). to assess the effects of application of nod factors on symbiotic activity and yield of pea, a two-year field experiment was conducted on a haplic luvisol developed from loess. nod factors were isolated from rhizobium leguminosarum bv. viciae strain gr09. pea seeds were treated with the nod factors (10⁻¹¹ m) or water (control) before planting. symbiotic activity was evaluated by measurements of ... | 2014 | 24786094 |
| genome-wide profiling of hfq-binding rnas uncovers extensive post-transcriptional rewiring of major stress response and symbiotic regulons in sinorhizobium meliloti. | the rna chaperone hfq is a global post-transcriptional regulator in bacteria. here, we used rnaseq to analyze rna populations from the legume symbiont sinorhizobium meliloti that were co-immunoprecipitated (coip-rna) with a flag-tagged hfq in five growth/stress conditions. hfq-bound transcripts (1315) were largely identified in stressed bacteria and derived from small rnas (srnas), both trans-encoded (6.4%) and antisense (asrnas; 6.3%), and mrnas (86%). pull-down with hfq recovered a small propo ... | 2014 | 24786641 |
| a comparative study of phase states of the peribacteroid membrane from yellow lupin and broad bean nodules. | a comparative study of the lipid bilayer phase status and structure of the outer membrane of free-living bradyrhizobium strain 359a (nod(+)fix(+)) and 400 (nod(+)fixl) or rhizobium leguminosarum 97 (nod(+)fix(+), effective) and 87 (nod(+)fixl, ineffective) has been carried out. also, the effect of the symbiotic pair combination on the lipid bilayer structure of the bacteroid outer membrane and peribacteroid membrane, isolated from the nodules of lupinus luteus l. or vicia faba l., has been studi ... | 2014 | 24804101 |
| evolution of mitochondria reconstructed from the energy metabolism of living bacteria. | the ancestors of mitochondria, or proto-mitochondria, played a crucial role in the evolution of eukaryotic cells and derived from symbiotic α-proteobacteria which merged with other microorganisms - the basis of the widely accepted endosymbiotic theory. however, the identity and relatives of proto-mitochondria remain elusive. here we show that methylotrophic α-proteobacteria could be the closest living models for mitochondrial ancestors. we reached this conclusion after reconstructing the possibl ... | 2014 | 24804722 |