| phytotoxicity attenuation in vigna radiata under heavy metal stress at the presence of biochar and n fixing bacteria. | this study assesses the effect of n-fixing bacteria and biochar synergism on plant growth and development of vigna mungo under heavy metal stress (hm). heavy metal stress is a worldwide problem, which causes critical effects on plant life due to oxidative stress. application of biochar is a recent biological remediation technique, which often leads to an immobilization of heavy metals in soil. . synergism of bacteria and biochar is a novel aspect to enhance plant growth under heavy metal stress. ... | 2017 | 27527669 |
| characterization of iron-sulfur clusters in flavin-containing opine dehydrogenase. | flavin-containing opine dehydrogenase from bradyrhizobium japonicum forms a heterooligomeric α4β4γ4 enzyme complex. an electron paramagnetic resonance spectroscopy analysis using wild-type and site-directed mutants revealed that [4fe-4s] and [2fe-2s] clusters bind to two different types of [fe-s] binding sites in the γ- and α-subunits, respectively. the latter was found to be important for structural folding and enzyme catalysis. | 2016 | 27388263 |
| redox-dependent dynamics in heme-bound bacterial iron response regulator (irr) protein. | the iron response regulator (irr) protein from bradyrhizobium japonicum mediates iron-dependent regulation of heme biosynthesis. irr degrades in response to heme availability through a process that involves the binding of heme to cys-29 in the heme regulatory motif (hrm) in the presence of molecular oxygen. in this work, we assessed the dynamics of one-electron reduction of heme-bound irr by monitoring the formation of transient intermediates by pulse radiolysis. hydrated electrons generated by ... | 2016 | 27379473 |
| the bradyrhizobium japonicum ferrous iron transporter feoab is required for ferric iron utilization in free living aerobic cells and for symbiosis. | the bacterium bradyrhizobium japonicum usda110 does not synthesize siderophores for iron utilization in aerobic environments, and the mechanism of iron uptake within symbiotic soybean root nodules is unknown. an mbfa bfr double mutant defective in iron export and storage activities cannot grow aerobically in very high iron medium. here, we found that this phenotype was suppressed by loss of function mutations in the feoab operon encoding ferrous (fe(2+)) iron uptake proteins. expression of the f ... | 2016 | 27288412 |
| 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 |
| characterization and biological activities of cyclic (1 → 3, 1 → 6)-β-glucans from bradyrhizobium japonicum. | to isolate cyclic (1 → 3, 1 → 6)-β-glucan from bradyrhizobium japonicum mtcc120, to characterize its structure and to study its biological activities. | 2016 | 27193761 |
| process optimization and kinetic modelling of cyclic (1→3, 1→6)-β-glucans production from bradyrhizobium japonicum mtcc120. | cyclic (1→3, 1→6)-β-glucans are water soluble, biocompatible polymers with potential applications in food and pharmaceutical industries but have not yet been exploited due to their poor yield. in the present study statistical experimental design methodology was employed to improve their production. initial screening indicated arabinose and peptone as best carbon and nitrogen source respectively, for glucan production. arabinose and osmolyte concentrations as well as ph significantly contributed ... | 2016 | 27046066 |
| polysaccharide-based bioflocculant template of a diazotrophic bradyrhizobium japonicum 36 for controlled assembly of agcl nanoparticles. | a simple and green method was developed for the biosynthesis of silver chloride nanoparticles, free from silver nanoparticles, using polysaccharide-based bioflocculant of a diazotrophic rhizobacteria bradyrhizobium japonicum 36 strain. the synthesized silver chloride nanoparticles were characterized by uv-vis, xrd, ft-ir and tem. the concentration-dependent and controllable method for silver chloride nanoparticles was developed. the biosynthesized silver chloride nanoparticles exhibited strong a ... | 2016 | 27039118 |
| metal-specific control of gene expression mediated by bradyrhizobium japonicum mur and escherichia coli fur is determined by the cellular context. | bradyrhizobium japonicum mur and escherichia coli fur are manganese- and iron-responsive transcriptional regulators, respectively, that belong to the same protein family. here, we show that neither mur nor fur discriminate between fe(2+) and mn(2+) in vitro nor is there a metal preference for conferral of dna-binding activity on the purified proteins. when expressed in e. coli, b. japonicum mur responded to iron, but not manganese, as determined by in vivo promoter occupancy and transcriptional ... | 2016 | 26998998 |
| hmus and hmuq of ensifer/sinorhizobium meliloti degrade heme in vitro and participate in heme metabolism in vivo. | ensifer meliloti is a nitrogen-fixing symbiont of the alfalfa legume able to use heme as an iron source. the transport mechanism involved in heme acquisition in e. meliloti has been identified and characterized, but the fate of heme once inside the cell is not known. in silico analysis of e. meliloti 1021 genome revealed no canonical heme oxygenases although two genes encoding putative heme degrading enzymes, smc01518 and hmus, were identified. smc01518 is similar to hmuq of bradyrhizobium japon ... | 2016 | 26906560 |
| structural and transcriptional characterization of a novel member of the soybean urease gene family. | in plants, ureases have been related to urea degradation, to defense against pathogenic fungi and phytophagous insects, and to the soybean-bradyrhizobium japonicum symbiosis. two urease isoforms have been described for soybean: the embryo-specific, encoded by eu1 gene, and the ubiquitous urease, encoded by eu4. a third urease-encoding locus exists in the completed soybean genome. the gene was designated eu5 and the putative product of its orf as sbu-iii. phylogenetic analysis shows that 41 plant ... | 2016 | 26874294 |
| functional analysis of alternative transcripts of the soybean rj2 gene that restricts nodulation with specific rhizobial strains. | the rj2 gene is a tir-nbs-lrr-type resistance gene in soybean (glycine max) that restricts root nodule symbiosis with a group of bradyrhizobium japonicum strains including usda122. rj2 generates two distinct transcript variants in its expression profile through alternative splicing. alternative splicing of rj2 is caused by the retention of the 86-bp intron 4. inclusion of intron 4 in mature mrna introduces an in-frame stop codon; as such, the alternative transcript is predicted to encode a trunc ... | 2016 | 26848549 |
| diversity and phylogeny of rhizobia associated with desmodium spp. in panxi, sichuan, china. | thirty-four rhizobial isolates were obtained from root nodules of four wild desmodium species growing in panxi, sichuan, china. according to the combined ardra and igs-rflp (cacai) cluster analysis, rhizobium, pararhizobium and mesorhizobium isolates outnumbered bradyrhizobium isolates. in general, the isolates representing the same species from the same site clustered together. furthermore, the four desmodium species were all nodulated by more than one rhizobial species. aflp and phenotypic ana ... | 2016 | 26654528 |
| [auxins and cytokinines synthesis by bradyrhizobium japonicum under flavonoids influence]. | research the ability of different by effectiveness symbiotic nitrogen-fixing soybean bacteria bradyrhizobium japonicum to the synthesis of phytohormones-stimulators auxins and cytokinins for the actions of plant flavonoids genistein and naringenin. | 2015 | 26638490 |
| synthesis of silver nanoparticles on the basis of low and high molar mass exopolysaccharides of bradyrhizobium japonicum 36 and its antimicrobial activity against some pathogens. | silver nanoparticles (snps) were synthesized on the basis of exopolysaccharides (low and high molar mass) of diazotrophic bradyrhizobium japonicum 36 strain. the synthesis of snps was carried out by direct reduction of silver nitrate with ethanol-insoluble (high molar mass, hmw) and ethanol-soluble (low molar mass, lmw) fractions of exopolysaccharides (eps), produced by diazotrophic strain b. japonicum 36. snps were characterized using uv-vis spectroscopy, transmission electron microscopy (tem), ... | 2016 | 26603749 |
| overexpression of d-amino acid oxidase from bradyrhizobium japonicum, enhances resistance to glyphosate in arabidopsis thaliana. | the glyphosate resistance in escherichia coli and arabidopsis was due to d-amino acid oxidase expression. transgenic glyphosate-resistant crops have a high percentage in the total area devoted to transgenic crops worldwide. d-amino acid oxidase (daao) can metabolize glyphosate by oxidative cleavage of the carbon-nitrogen bond on the carboxyl side and yield aminomethyl phosphonic acid and glyoxylate, which are less toxic to plants than glyphosate. to date, reports on the use of daao to enhance gl ... | 2015 | 26350405 |
| microrna160 dictates stage-specific auxin and cytokinin sensitivities and directs soybean nodule development. | legume nodules result from coordinated interactions between the plant and nitrogen-fixing rhizobia. the phytohormone cytokinin promotes nodule formation, and recent findings suggest that the phytohormone auxin inhibits nodule formation. here we show that microrna160 (mir160) is a key signaling element that determines the auxin/cytokinin balance during nodule development in soybean (glycine max). mir160 appears to promote auxin activity by suppressing the levels of the arf10/16/17 family of repre ... | 2015 | 26287653 |
| efficient synthesis of the intermediate of abacavir and carbovir using a novel (+)-γ-lactamase as a catalyst. | the enantiomers of 2-azabicyclo[2.2.1]hept-5-en-3-one (γ-lactam) are key chiral synthons in the synthesis of antiviral drugs such as carbovir and abacavir. (+)-γ-lactamase can be used as a catalyst in the enzymatic preparation of optically pure (-)-γ-lactam. here, a (+)-γ-lactamase discovered from bradyrhizobium japonicum usda 6 by sequence-structure guided genome mining was cloned, purified and characterized. the enzyme possesses a significant catalytic activity towards γ-lactam. the active sit ... | 2015 | 26235952 |
| role of the extracytoplasmic function sigma factor carq in oxidative response of bradyrhizobium japonicum. | as a nitrogen-fixing bacterium, bradyrhizobium japonicum can establish a symbiotic relationship with the soybean plant (glycine max). to be a successful symbiont, b. japonicum must deal with plant defense responses, such as an oxidative burst. our previous functional genomics study showed that carq (bll1028) encoding extracytoplasmic function (ecf) sigma factor was highly expressed (107.8-fold induction) under oxidative stress. little is known about the underlying mechanisms of how carq responds ... | 2015 | 26224455 |
| characterization of mocr, a gntr-like transcriptional regulator, in bradyrhizobium japonicum: its impact on motility, biofilm formation, and soybean nodulation. | bradyrhizobium japonicum is a gram-negative soil bacterium that can fix nitrogen into ammonia by developing a symbiotic relationship with the soybean plant. mocr proteins make up a subfamily of gntr superfamily, one of the most widely distributed and prolific groups of the helix-turn-helix transcription factors. in this study, we constructed a mutant strain for mocr (blr6977) to investigate its role in cellular processes and symbiosis in b. japonicum. although growth rate and morphology of the m ... | 2015 | 26224454 |
| the origin of specificity and insight into recognition between an aminoacyl carrier protein and its partner ligase. | acyl carrier proteins (acps) are among the most promiscuous proteins in terms of protein-protein interactions and it is quite puzzling how acps select the correct partner between many possible upstream and downstream binding proteins. to address this question, we performed molecular dynamics simulations on dimeric bradyrhizobium japonicum gly:cp ligase 1 to inspect the origin of its selectivity towards the three types of carrier proteins, namely holocp, apocp, and holocp-gly, which only differ i ... | 2015 | 26129823 |
| inoculation with an enhanced n2 -fixing bradyrhizobium japonicum strain (usda110) does not alter soybean (glycine max merr.) response to elevated [co2 ]. | this study tested the hypothesis that inoculation of soybean (glycine max merr.) with a bradyrhizobium japonicum strain (usda110) with greater n2 fixation rates would enhance soybean response to elevated [co2 ]. in field experiments at the soybean free air co2 enrichment facility, inoculation of soybean with usda110 increased nodule occupancy from 5% in native soil to 54% in elevated [co2 ] and 34% at ambient [co2 ]. despite this success, inoculation with usda110 did not result in greater photos ... | 2015 | 26012898 |
| identification and functional characterization of soybean root hair micrornas expressed in response to bradyrhizobium japonicum infection. | three soybean [glycine max (l) merr.] small rna libraries were generated and sequenced using the illumina platform to examine the role of mirnas during soybean nodulation. the small rna libraries were derived from root hairs inoculated with bradyrhizobium japonicum (in_rh) or mock-inoculated with water (un_rh), as well as from the comparable inoculated stripped root samples (i.e. inoculated roots with the root hairs removed). sequencing of these libraries identified a total of 114 mirnas, includ ... | 2016 | 25973713 |
| predominant populations of indigenous soybean-nodulating bradyrhizobium japonicum strains obtained from organic farming systems in minnesota. | bradyrhizobium from organic fields in minnesota were isolated and genotyped to assess diversity of soybean-bradyrhizobia in organic farming systems that can be used to improve soybean productivity. | 2015 | 25660818 |
| prediction of potential novel micrornas in soybean when in symbiosis. | micrornas (mirnas) are small molecules, noncoding proteins that are involved in many biological processes, especially in plants; among these processes is nodulation in the legume. biological nitrogen fixation is a key process, with critical importance to the soybean crop. this study aimed to identify the potential of novel mirnas to act during the root nodulation process. we utilized a set of transcripts that were differentially expressed in soybean roots 10 days after inoculation with bradyrhiz ... | 2014 | 25366746 |
| a single amino acid substitution affects the substrate specificity of the seryl-trna synthetase homologue. | recently described and characterized bradyrhizobium japonicum glycine:[carrier protein] ligase 1 (bj gly:cp ligase 1), a homologue of methanogenic type seryl-trna synthetase (serrs) is an intriguing enzyme whose physiological role is not yet known. while aminoacyl-trna synthetases supply ribosome with amino acids for protein biosynthesis, this homologue transfers the activated amino acid to a specific carrier protein. despite remarkable structural similarity between the bj gly:cp ligase 1 and th ... | 2014 | 25272963 |
| enzymatic preparation of optically pure (+)-2-azabicyclo[2.2.1]hept-5-en-3-one by (-)-γ-lactamase from bradyrhizobium japonicum usda 6. | whole cells of bradyrhizobium japonicum usda 6 showed both (+)-γ-lactamase activity and (-)-γ-lactamase activity. insight into the genome of b. japonicum usda 6 revealed two potential γ-lactamases: a type i (+)-γ-lactamase and a (-)-γ-lactamase, making it the first strain to contain two totally different enantioselective lactamases. both recombinant enzymes could easily be used to prepare either optically pure (+)-γ-lactam ((+)-2-azabicyclo[2.2.1]hept-5-en-3-one) or optically pure (-)-γ-lactam ( ... | 2014 | 25240615 |
| insilico model for prediction of lateral gene transfer in rhodopseudomonas paulistris. | study of evolutionary phenomenon is of great interest to biologists in discovering the secrets of life. the presence of reticulation events due to lateral gene transfer (lgt) among species poses new challenges for such evolutionary studies. in this paper an attempt has been made to develop an insilico model to predict lgt in the rhodopseudomonas paulistris. neighbour joining method is employed to generate phylogenetic tree of 26 sequences of alphaproteobacteria and one sequence of cyanobacteria ... | 2014 | 25108459 |
| increased expression of fe-chelatase leads to increased metabolic flux into heme and confers protection against photodynamically induced oxidative stress. | fe-chelatase (fech, ec 4.99.1.1) inserts fe(2+) into protoporphyrin ix (proto ix) to form heme, which influences the flux through the tetrapyrrole biosynthetic pathway as well as fundamental cellular processes. in transgenic rice (oryza sativa), the ectopic expression of bradyrhizobium japonicum fech protein in cytosol results in a substantial increase of fech activity compared to wild-type (wt) rice and an increasing level of heme. interestingly, the transgenic rice plants showed resistance to ... | 2014 | 25037078 |
| the nitrate-sensing nasst system regulates nitrous oxide reductase and periplasmic nitrate reductase in bradyrhizobium japonicum. | the soybean endosymbiont bradyrhizobium japonicum is able to scavenge the greenhouse gas n2o through the n2o reductase (nos). in previous research, n2o emission from soybean rhizosphere was mitigated by b. japonicum nos(++) strains (mutants with increased nos activity). here, we report the mechanism underlying the nos(++) phenotype. comparative analysis of nos(++) mutant genomes showed that mutation of bll4572 resulted in nos(++) phenotype. bll4572 encodes nass, the nitrate (no3(-))-sensor of th ... | 2014 | 24947409 |
| [influence of bradyrhizobium japonicum ykm b-6035 inoculation on the microstructure of soybean rhizosphere cenosis and photosynthetic apparatus]. | development of bradyrhizobium japonicum ykm b-6035 bacterial cells in suspension culture, aseptic soil and rhizosphere of soybean plants inoculated by nodulate bacteria were investigated. the increase of bacteria number on the surface of main root and rhizosphere was determined in nodulated soybean plants. photosynthetic apparatus of inoculated plants increased due to morphological characteristics: the leaf blade area and width of mezophyll palisade and spongy layers. morphological changes in th ... | 2014 | 24800509 |
| 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 |
| soybean ureases, but not that of bradyrhizobium japonicum, are involved in the process of soybean root nodulation. | ureases are abundant in plants, bacteria, and in the soil, but their role in signaling between soybean and soil microorganisms has not been investigated. the bacterium bradyrhizobium japonicum forms nitrogen-fixing nodules on soybean roots. here, we evaluated the role(s) of ureases in the process of soybean nodulation. chemotaxis assays demonstrated that soybean and jack bean ureases were more chemotactic toward bacterial cells than the corresponding plant lectins. the eu1-a,eu4 soybean, deficie ... | 2014 | 24716625 |
| genetic diversity patterns and functional traits of bradyrhizobium strains associated with pterocarpus officinalis jacq. in caribbean islands and amazonian forest (french guiana). | pterocarpus officinalis jacq. is a legume tree native to the caribbean islands and south america growing as a dominant species in swamp forests. to analyze (i) the genetic diversity and (ii) the symbiotic properties of its associated nitrogen-fixing soil bacteria, root nodules were collected from p. officinalis distributed in 16 forest sites of the caribbean islands and french guiana. the sequencing of the 16s-23s ribosomal rna intergenic spacer region (its) showed that all bacteria belonged to ... | 2014 | 24595907 |
| inactivation of the lpcc gene alters surface-related properties and symbiotic capability of bradyrhizobium japonicum. | we investigated the role of the bradyrhizobium japonicum lpcc gene, encoding a mannosyl transferase, involved in the lipopolysaccharide (lps) biosynthesis. the inactivation of the lpcc gene considerably altered the lps structure and the cell surface properties. lps analysis showed that the lpcc mutant js715 had an abnormal lps structure deficient in o-antigen. the cell surface hydrophobicity increased approximately threefold in js715 compared to the wild type. the increased cell surface hydropho ... | 2014 | 24521100 |
| gibberellin oxidase activities in bradyrhizobium japonicum bacteroids. | bradyrhizobium japonicum bacteroids isolated from root nodules of soybean (glycine max.) plants converted the gibberellin (ga) precursor [(14)c1]ga12 into several products identified by combined gas chromatography-mass spectrometry as [(14)c1]ga24, [(14)c1]ga9, [(14)c1]ga15, ga9 17-nor-16-one and unidentified products. the oxidation of ga12, catalyzed by the ga 20-oxidase, was present in symbiotic bacteroids from plants around flowering, but not in bacteroids from plants at either an early veget ... | 2014 | 24378220 |
| homology modeling and docking studies of bjgl, a novel (+) gamma-lactamase from bradyrhizobium japonicum. | (+) gamma-lactamases are enantioselective hydrolysis enzymes that can be used to produce optically pure (-) gamma-lactam, an important pharmaceutical intermediate for the anti-aids drug abacavir. in this study, homology modeling and molecular dynamic simulation studies of a 3d homology model of bjgl, a novel (+) gamma-lactamase from bradyrhizobium japonicum, were constructed and refined. the specific substrate (+) gamma-lactam and its enantiomer (-) gamma-lactam which can not be hydrolyzed was d ... | 2014 | 24215997 |
| antioxidant defense system responses and role of nitrate reductase in the redox balance maintenance in bradyrhizobium japonicum strains exposed to cadmium. | in this work, we evaluated the effects of cadmium (cd) on the antioxidant defense system responses and the role of nitrate reductase (nr) in the redox balance maintenance in bradyrhizobium japonicum strains. for that, b. japonicum usda110 and its nr defective mutant strain (grpa1) were used. results showed that the addition of 10μm cd did not modify the aerobic growth of the wild type strain while the mutant strain was strongly affected. anaerobic growth revealed that only the parental strain wa ... | 2013 | 24034434 |
| inoculation with bradyrhizobium japonicum enhances the organic and fatty acids content of soybean (glycine max (l.) merrill) seeds. | soybean (glycine max (l.) merrill) is one of the most important food crops for human and animal consumption, providing oil and protein at relatively low cost. the least expensive source of nitrogen for soybean is the biological fixation of atmospheric nitrogen by the symbiotic association with soil bacteria, belonging mainly to the genus bradyrhizobium. this study was conducted to assess the effect of the inoculation of g. max with bradyrhizobium japonicum on the metabolite profile and antioxida ... | 2013 | 23993531 |
| changes in bacterial co2 fixation with depth in agricultural soils. | soils were incubated continuously in an atmosphere of (14)co2 and the distribution of labeled c into soil organic carbon ((14)c-soc) was determined at 0-1, 1-5, and 5-17 cm down the profile. significant amounts of (14)c-soc were measured in paddy soils with a mean of 1,180.6 ± 105.2 mg kg(-1) at 0-1 cm and 135.3 ± 47.1 mg kg(-1) at 1-5 cm. this accounted for 5.9 ± 0.7% and 0.7 ± 0.2%, respectively, of the total soil organic carbon at these depths. in the upland soils, the mean (14)c-soc concentr ... | 2014 | 23989975 |
| [novel nadph-dependent l-aspartate dehydrogenases from the mesophilic nitrogen-fixing bacteria rhodopseudomonas palustris and bradyrhizobium japonicum]. | the genes encoding putative l-aspartate dehydrogenases (ec 1.4.1.21, adh) from the mesophilic nitrogen-fixing bacteria rhodopseudomonas palustris and bradyrhizobium japonicum were cloned and expressed in escherichia coli. the respective enzymes in the form of hybrid proteins with n-terminal hexahistidine tags were purified to apparent homogeneity. both enzymes catalyzed in vitro the reductive amination of oxaloacetate to l-aspartate by an order faster than the reverse reaction at a respective ph ... | 2013 | 23795474 |
| transcription analyses of gmichg, a gene coding for a β-glucosidase that catalyzes the specific hydrolysis of isoflavone conjugates in glycine max (l.) merr. | isoflavone conjugate-hydrolyzing β-glucosidase (gmichg) of soybeans [glycine max (l.) merr.] catalyzes the specific hydrolysis of isoflavone conjugates (β-7-o-(malonyl)glucosides of isoflavones) to produce free isoflavones. in this study, changes in the transcription levels of gmichg in the individual organs of soybean seedlings (cv. enrei) in response to microbial infection and abiotic stresses were analyzed and compared with those of genes coding for 2-hydroxyisoflavanone synthase (gmifs) and ... | 2013 | 23683924 |
| polyphasic evidence supporting the reclassification of bradyrhizobium japonicum group ia strains as bradyrhizobium diazoefficiens sp. nov. | bradyrhizobium japonicum was described from soybean root-nodule bacterial isolates. since its description, several studies have revealed heterogeneities among rhizobia assigned to this species. strains assigned to b. japonicum group ia have been isolated in several countries, and many of them are outstanding soybean symbionts used in inoculants worldwide, but they have also been isolated from other legume hosts. here, we summarize published studies that indicate that group ia strains are differe ... | 2013 | 23504968 |
| an overview of the metabolic differences between bradyrhizobium japonicum 110 bacteria and differentiated bacteroids from soybean (glycine max) root nodules: an in vitro 13c- and 31p-nuclear magnetic resonance spectroscopy study. | bradyrhizobium japonicum is a symbiotic nitrogen-fixing soil bacteria that induce root nodules formation in legume soybean (glycine max.). using (13)c- and (31)p-nuclear magnetic resonance (nmr) spectroscopy, we have analysed the metabolite profiles of cultivated b. japonicum cells and bacteroids isolated from soybean nodules. our results revealed some quantitative and qualitative differences between the metabolite profiles of bacteroids and their vegetative state. this includes in bacteroids a ... | 2013 | 23480054 |
| ethyl tert-butyl ether (etbe) biodegradation by a syntrophic association of rhodococcus sp. ifp 2042 and bradyrhizobium sp. ifp 2049 isolated from a polluted aquifer. | ethyl tert-butyl ether (etbe) enrichment was obtained by adding contaminated groundwater to a mineral medium containing etbe as the sole carbon and energy source. etbe was completely degraded to biomass and co2 with a transient production of tert-butanol (tba) and a final biomass yield of 0.37 ± 0.08 mg biomass (dry weight).mg(-1) etbe. two bacterial strains, ifp 2042 and ifp 2049, were isolated from the enrichment, and their 16s rrna genes (rrs) were similar to rhodococcus sp. (99 % similarity ... | 2013 | 23474617 |
| keeping pase with weft: shweft-pase pulse sequences for 1h nmr spectra of highly paramagnetic molecules. | metalloproteins are a category of biomolecules in which the metal site is usually the locus of activity or function. in many cases, the metal ions are paramagnetic or have accessible paramagnetic states, many of which can be studied using nmr spectroscopy. extracting useful information from (1)h nmr spectra of highly paramagnetic proteins can be difficult because the paramagnetism leads to large resonance shifts (~400 ppm), extremely broad lines, extreme baseline nonlinearity, and peak shape dis ... | 2013 | 23401036 |
| bradyrhizobium arachidis sp. nov., isolated from effective nodules of arachis hypogaea grown in china. | twenty-three bacterial strains isolated from root nodules of arachis hypogaea and lablab purpureus grown in five provinces of china were classified as a novel group within the genus bradyrhizobium by analyses of pcr-based rflp of the 16s rrna gene and 16s-23s igs. to determine their taxonomic position, four representative strains were further characterized. the comparative sequence analyses of 16s rrna and six housekeeping genes clustered the four strains into a distinctive group closely related ... | 2013 | 23295123 |
| [role of biocompatible adhesives in the increase of rhizobia physiological activity and productivity of soybean-rhizobia symbiosis]. | on the basis of natural exopolysaccharide xanthan and exopolyacrylamide the sticky-gene composition has been developed. addition of that composition to the culture medium provided a 26.3 times higher viability of bradyrhizobium japonicum ucm b-6035 cells during its storage. introduction of plant growth regulators biosil or ivin into this composition increased the survival of rhizobia. application of gel inoculant b. japonicum favored more intensive growth of rhizosphere microorganisms, nutrient' ... | 2015 | 23293821 |
| response of soybean to seed inoculation with bradyrhizobium japonicum and with mixed inoculants of b. japonicum and azotobacter chroococcum. | effects of pre-sowing soybean seed inoculation with bradyrhizobium japonicum alone or with mixed inoculants containing soybean rhizobia and azotobacter chroococcum were compared. in the pot experiment all the tested strains of soybean rhizobia in pure cultures or in mixtures with a. chroococcum significantly improved nodulation of soybean plants and seed yields of this crop. in micro-plot experiments pre-sowing soybean seeds treatment with the inoculant containing the most effective strain 94p o ... | 2013 | 24730143 |
| a simple and effective strategy for solving the problem of inclusion bodies in recombinant protein technology: his-tag deletions enhance soluble expression. | the formation of inclusion bodies (ibs) in recombinant protein biotechnology has become one of the most frequent undesirable occurrences in both research and industrial applications. so far, the pet system is the most powerful system developed for the production of recombinant proteins when escherichia coli is used as the microbial cell factory. also, using fusion tags to facilitate detection and purification of the target protein is a commonly used tactic. however, there is still a large fracti ... | 2013 | 23250226 |
| arsenic effect on the model crop symbiosis bradyrhizobium-soybean. | soybean (glycine max) is often being cultivated in soils with moderate to high arsenic (as) concentrations or under irrigation with as contaminated groundwater. the purpose of this study was to determine the effect of as on soybean germination, development and nodulation in soybean-bradyrhizobium japonicum e109 symbiosis, as a first-step approach to evaluate the impact of as on soybean production. semi-hydroponic assays were conducted using soybean seedlings inoculated and non-inoculated with b. ... | 2013 | 23228549 |
| fixk₂, a key regulator in bradyrhizobium japonicum, is a substrate for the protease clpap in vitro. | fixk₂ is a crp-like transcription factor that controls the endosymbiotic lifestyle of bradyrhizobium japonicum. the reason for its noticeable protease sensitivity was explored here. the repertoire of clp chaperone-proteases in b. japonicum was examined, and specifically clpap₁ and clpxp₁ were purified and tested. fixk₂ was found to be degraded by clpap₁ but not by clpxp₁. degradation was inhibited by the clps₁ adaptor protein, indicating that fixk₂ is a direct substrate for clpap₁. the last 12 a ... | 2013 | 23187170 |
| swarming motility in bradyrhizobium japonicum. | flagellar-driven bacterial motility is an important trait for colonization of natural environments. bradyrhizobium japonicum is a soil species that possesses two different flagellar systems: one subpolar and the other lateral, each with a filament formed by a different set of flagellins. while synthesis of subpolar flagellins is constitutive, translation of lateral flagellins was detected in rhizobia grown with l-arabinose, but not with d-mannitol as sole carbon source, independently of whether ... | 2013 | 23124116 |
| thioredoxin-like protein tlpa from bradyrhizobium japonicum is a reductant for the copper metallochaperone scoi. | tlpa and scoi of bradyrhizobium japonicum are membrane-anchored thioredoxin-like proteins oriented towards the periplasm. tlpa is a protein-disulfide reductase. scoi is a copper chaperone for cytochrome oxidase biogenesis. tlpa with its negative redox potential (e(o') -256 mv) was shown here to reduce oxidized scoi, for which we determined a less negative e(o') (-160 mv). the fast forward reaction (rate constant 9.4×10(4) m(-1) s(-1)) was typical for physiologically relevant disulfide exchange r ... | 2012 | 23123159 |
| increased hydrogen production in co-culture of chlamydomonas reinhardtii and bradyrhizobium japonicum. | co-cultivation of bradyrhizobium japonicum with chlamydomonas reinhardtii strain cc849 or the transgenic strain lba, which was hetero-expressed the gene of the soybean leghemoglobin apoprotein lba in chloroplasts of the strain cc849, in tris-acetate-phosphate (tap) or tap-sulfur free media, improved h(2) yield. h(2) production was 14 times and growth was 26% higher when strain lba and b. japonicum were co-cultured, as compared with cultivation of the algal strain alone under the same conditions. ... | 2012 | 22940317 |
| transient nod factor-dependent gene expression in the nodulation-competent zone of soybean (glycine max [l.] merr.) roots. | all lateral organ development in plants, such as nodulation in legumes, requires the temporal and spatial regulation of genes and gene networks. a total mrna profiling approach using rna-seq to target the specific soybean (glycine max) root tissues responding to compatible rhizobia [i.e. the zone of nodulation (zon)] revealed a large number of novel, often transient, mrna changes occurring during the early stages of nodulation. focusing on the zon enabled us to discard the majority of root tissu ... | 2012 | 22863334 |
| soybean seed lectin prevents the accumulation of s-adenosyl methionine synthetase and the s1 30s ribosomal protein in bradyrhizobium japonicum under c and n starvation. | soybean lectin (sbl) participates in the recognition between bradyrhizobium japonicum and soybean although its role remains unknown. to search for changes in the proteome in response to sbl, b. japonicum usda 110 was incubated for 12 h in a c- and n-free medium with or without sbl (10 μg ml(-1)), and the soluble protein profiles were compared. two polypeptides, s-adenosyl-methionine synthetase (metk) and the 30s ribosomal protein s1 (rpsa), were found only in the fractions from rhizobia incubate ... | 2012 | 22782468 |
| a comparative proteomics analysis in roots of soybean to compatible symbiotic bacteria under flooding stress. | a proteomics approach was used to evaluate the effects of flooding stress on early symbiotic interaction between soybean roots and soil bacteria, bradyrhizobium japonicum. three-day-old soybean was inoculated with b. japonicum followed by flooding. the number of root hairs in seedlings, without or with flooding stress, was increased after 3 days of inoculation. proteins were extracted from roots and separated by two-dimensional polyacrylamide gel electrophoresis. out of 219 protein spots, 14 and ... | 2012 | 22692703 |
| identification of systemic responses in soybean nodulation by xylem sap feeding and complete transcriptome sequencing reveal a novel component of the autoregulation pathway. | establishment of the nitrogen-fixing nodulation symbiosis between legumes and rhizobia requires plant-wide reprogramming to allow infection and development of nodules. nodulation is regulated principally via a mechanism called autoregulation of nodulation (aon). aon is dependent on shoot and root factors and is maintained by the nodulation autoregulation receptor kinase (nark) in soybean. we developed a bioassay to detect root-derived signalling molecules in xylem sap of soybean plants which may ... | 2012 | 22624681 |
| production and function of jasmonates in nodulated roots of soybean plants inoculated with bradyrhizobium japonicum. | little is known regarding production and function of endogenous jasmonates (jas) in root nodules of soybean plants inoculated with bradyrhizobium japonicum. we investigated (1) production of jasmonic acid (ja) and 12-oxophytodienoic acid (opda) in roots of control and inoculated plants and in isolated nodules; (2) correlations between jas levels, nodule number, and plant growth during the symbiotic process; and (3) effects of exogenous ja and opda on nodule cell number and size. in roots of cont ... | 2012 | 22547296 |
| lack of glyphosate resistance gene transfer from roundup ready soybean to bradyrhizobium japonicum under field and laboratory conditions. | a field study was conducted at the russell e. larson agricultural research center to determine the effect of transgenic glyphosate-resistant soybean in combination with herbicide (roundup) application on its endosymbiont bradyrhizobium japonicum. dna of bacteroids from isolated nodules was analysed for the presence of the transgenic 5-enolpyruvylshikimate-3-phosphate synthase (cp4-epsps) dna sequence using polymerase chain reaction (pcr). to further assess the likelihood that the epsps gene may ... | 2015 | 22351985 |
| short communication: screening of native and foreign bradyrhizobium japonicum strains for high n2 fixation in soybean. | four local rhizobia isolates selected after two screening experiments and five usda bradyrhizobium japonicum strains were estimated for n2 fixation in soybean using the (15)n isotope dilution technique. strain usda 110 was superior to the local isolates in nodulation and n2 fixation when inoculated onto soybean cv tgx 1497-id in a nigerian soil and could therefore be used as an inoculant for enhanced n2 fixation in soybean in nigeria. | 1996 | 24415429 |
| presence of rhizobia in soils in somalia. | bradyrhizobium japonicum was absent and only low numbers of rhizobium were present in nodulating forage legumes in 13 soil samples from the jubba and shabelle rivers of somalia. | 1995 | 24415006 |
| bradhyrhizobium japonicum hydrogen-ubiquinone oxidoreductase activity: quinone specificity, inhibition by quinone analogs, and evidence for separate sites of electron acceptor reactivity. | the purified h2-uptake hydrogenase of bradyrhizobium japonicum, containing no cytochrome b, catalyzed efficient h2-ubiquinone oxidoreductase activity. hydrogen-oxidizing membranes also catalyzed h₂-ubiquinone oxidoreductase activity, and the site of ubiquinone reduction was localized to the he-quinone oxidoreductase complex based on comparative antimycin a and hqno titrations of both h₂-ubiquinone-1 oxidoreductase and ubiquinol-1 oxidase activities. a variety of quinones could function as electr ... | 1995 | 25507405 |
| bradhyrhizobium japonicum hydrogen-ubiquinone oxidoreductase activity: quinone specificity, inhibition by quinone analogs, and evidence for separate sites of electron acceptor reactivity. | the purified h2-uptake hydrogenase of bradyrhizobium japonicum, containing no cytochrome b, catalyzed efficient h2-ubiquinone oxidoreductase activity. hydrogen-oxidizing membranes also catalyzed h₂-ubiquinone oxidoreductase activity, and the site of ubiquinone reduction was localized to the he-quinone oxidoreductase complex based on comparative antimycin a and hqno titrations of both h₂-ubiquinone-1 oxidoreductase and ubiquinol-1 oxidase activities. a variety of quinones could function as electr ... | 1995 | 25423682 |
| identification and inter-relationship analysis of bradyrhizobium japonicum strains by restriction fragment length polymorphism (rflp) and random amplified polymorphic dna (rapd). | genomic dna of 13 bradyrhizobium japonicum strains was prepared and analysed by restriction fragment length polymorphism (rflp) with nif and nod probes, and by random amplified polymorphic dna (rapd) with 11 primers of arbitrary nucleotide sequence. polymorphism was observed in both analyses. the rflp and rapd banding patterns of different strains were used to calculate genetic divergence and to construct phylogenetic trees, allowing studies on the relationships between the strains. rflp with ni ... | 1994 | 24421188 |
| polyclonal antisera production by immunization with mixed cell antigens of different rhizobial species. | somatic antigens of bradyrhizobium japonicum, rhizobium sp. (cicer arietinum) and rhizobium sp. (leucaena leucocephala) were prepared as standard, single-species type from cultured cells. equal numbers of the cells of these rhizobia were then combined to obtain a mixed-rhizobial-species antigen preparation. rabbits were immunized either with the standard, single-species type or with the mixed-rhizobial-species antigen preparations. the antisera developed from the mixed antigen immunization conta ... | 1994 | 24421129 |
| the biosynthesis of bacterial and plastidic c-type cytochromes. | the biosynthesis of bacterial and plastidic c-type cytochromes includes several steps that occur post-translationally. in the case of bacterial cytochromes, the cytosolically synthesized pre-proteins are translocated across the cytoplasmic membrane, the pre-proteins are cleaved to their mature forms and heme is ligated to the processed apoprotein. although heme attachment has not been studied extensively at the biochemical level, molecular genetic approaches suggest that the reaction generally o ... | 1994 | 24311284 |
| improved culture media for growth of bradyrhizobium japonicum. | a freshly-prepared yeast extract at 30 or 50 g/l improved the growth of bradyrhizobium japonicum semia 587 in a 5-l stirred fermenter. monosodium glutamate or a commercial yeast extract at 2.0 g/l almost doubled cell mass productivity and cell viability when added at the end of the first exponential growth phase. | 1994 | 24420898 |
| hydrogenase in bradyrhizobium japonicum: genetics, regulation and effect on plant growth. | a region of 15 kbp dna located on the chromosome of bradyrhizobium japonicum is essential for a hup(+) phenotype and contains the hydrogenase structural genes. during the last few years, other genes with various functions related to hydrogenase oxidation, such as ni(2+) incorporation into the hydrogenase enzyme, electron transport from hydrogenase to o2, and regulation of hydrogenase expression in free-living conditions, have been identified in this region. a region in front of the hydrogenase s ... | 1993 | 24420286 |
| accumulation of the phytoalexin, glyceollin, in root nodules of soybean formed by effective and ineffective strains ofbradyrhizobium japonicum. | nitrogen fixation in root nodules formed by strain 2143 ofbradyrhizobium japonicum andglycine max (l.) merr. cv williams 82 reaches a maximum at 21 to 28 days postinoculation and then begins to decline. the phytoalexin, glyceollin, accumulates in nodules coincident with the decline in nitrogen fixation. nodules formed by strain 3122, which are unable to fix nitrogen, accumulate even higher levels of glyceollin and do so beginning 21 days postinoculation even though these nodules contain no recov ... | 1992 | 24254143 |
| chitinase and peroxidase in effective (fix(+)) and ineffective (fix (-)) soybean nodules. | chitinase and peroxidase, two enzymes thought to be involved in the defense of plants against pathogens, were measured in soybean (glycine max l. merr.) roots and in nodules colonized by bradyrhizobium japonicum strains differing in their symbiotic potential. activities of both enzymes were higher in nodules than in roots. in "effective", nitrogen-fixing nodules, colonized by wild-type bacteria, chitinase and peroxidase activities had low levels in the central infected zone and were enhanced pri ... | 1992 | 24178068 |
| real continuous biomass production ofbradyrhizobium japonicum in a veterinary vaccine production unit. | in a real continuous culture,bradyrhizobium japonicum strain 1755 was maintained in the 'göttingen bioreactor unit' developed to produce veterinary bacterial vaccines for a period of 110 days without contamination or mutations. the average yield of viable bacteria over the whole period was more than 10(10)/ml. | 1992 | 24425338 |
| response of symbiotic interrelationship between soybean and the indigenous or inoculated microsymbiont,bradyrhizobium japonicum, to soil application of manganese and molybdenum. | soybean nodulation was induced indigenously by three strains ofbradyrhizobium japonicum inoculated in each of the two previous seasons. the same strains were applied, as a peat-based inoculum in similar cell density as the indigenous ones, to a rhizobia-free soll from the same field. inoculation was tested under soll application of 10 or 20 ppm mn and/or 2 or 4 ppm mo. inoculation with the peat-based inoculum significantly increased nodule numbers and weight, dry weight, n content and mg n/g of ... | 1990 | 24430068 |
| vesicular-arbuscular mycorrhizas of wild-type soybean and non-nodulating mutants with glomus mosseae contain symbiosis-specific polypeptides (mycorrhizins), immunologically cross-reactive with nodulins. | wild-type soybean (glycine max l. merr. cv. bragg) plants and two soybean mutants derived from cv. bragg (nod 49 and nod 139) unable to form nodules with bradyrhizobium japonicum were compared with regard to their reaction to the vesicular-arbuscular mycorrhizal fungus glomus mosseae. the roots from wild-type and mutant plants entered equally well into vesicular-arbuscular mycorrhiza symbiosis. polyadenylated rna was isolated from nodule-free mycorrhizal and non-mycorrhizal roots of wild-type an ... | 1990 | 24196994 |
| pectate distribution and esterification in dubautia leaves and soybean nodules, studied with a fluorescent hybridization probe. | carbohydrate-hybridization probes (vreeland and laetsch, 1989, planta (177, 423-434) were used to localize the homogalacturonan (pectate) component of pectins in the cell walls of leaves and soybean root nodules. leaves of two species of the dicotyledon dubautia were compared; these species contain much pectin but differ in their tissue water relations with respect to their cell-wall properties. maturation of the primary cell walls in nodules was studied in the bradyrhizobium japonicum-glycine m ... | 1989 | 24212485 |
| peribacteroid membrane nodulin gene induction by bradyrhizobium japonicum mutants. | seventeen translation products from glycine max root mrna precipitated with antiserum prepared against a peribacteroid membrane preparation from effective root nodules. messenger rna from fix (+) nodules coded for these 17 products plus 7 other nodule-specific polypeptides which bound to the antiserum. of these 7 nodulins only 4 were present when nodules were infected with bradyrhizobium japonicum 110 rif 15 2960, which induces the plant to produce 'empty' peribacteroid membranes. in nodules inf ... | 1989 | 24272866 |
| the occurrence of leghemoglobin protein in the uninfected interstitial cells of soybean root nodules. | the distribution of leghemoglobin (lb) in resin-embedded root nodules of soybean (glycine max (l.) merr.) was investigated using immunogold labeling. using anti-lb immunoglobulin g and protein a-gold, lb or its apoprotein was detected both in cells infected by bradyrhizobium japonicum and in uninfected interstitial cells. leghemoglobin was present in the cytoplasm, exclusive of the organelles, and in the nuclei of both cell types. in a comparison of the density of labeling in adjacent pairs of i ... | 1988 | 24221924 |
| visualization of bioluminescence as a marker of gene expression in rhizobium-infected soybean root nodules. | the linked structural genes lux a and lux b, encoding bacterial luciferase of a marine bacterium vibrio harveyi, were fused with the nitrogenase nifd promoter from bradyrhizobium japonicum and with the p1 promoter of pbr322. both fusions were integrated into the b. japonicum chromosome by site-specific recombination. soybean roots infected with the two types of rhizobium transconjugants formed nitrogen-fixing nodules that produced bright blue-green light. cells containing the p1 promoter/lux ab ... | 1988 | 24277587 |
| enhanced nodule initiation on alfalfa by wild-typerhizobium meliloti co-inoculated withnod gene mutants and other bacteria. | nodule formation on alfalfa (medicago sativa l.) roots was determined at different inoculum dosages for wild-typerhizobium meliloti strain rcr2011 and for various mutant derivatives with altered nodulation behavior. the number of nodules formed on the whole length of the primary roots was essentially constant regardless of initial inoculum dosage or subsequent bacterial multiplication, indicative of homeostatic regulation of total nodule number. in contrast, the number of nodules formed in just ... | 1988 | 24221521 |
| particle density and protein composition of the peribacteroid membrane from soybean root nodules is affected by mutation in the microsymbiont bradyrhizobium japonicum. | particle frequency of the peribacteroid membrane (pbm) from nodules of glycine max (l.) merr. cv. maple arrow infected with bradyrhizobium japonicum 61-a-101 (wild-type strain) was determined by freeze-fracturing to be about 2200·μm(-2) in the protoplasmic fracture face and 700·μm(-2) in the exoplasmic fracture face. in membranes isolated from nodules infected with the mutant rh 31-marburg of b. japonicum, the particle frequency was similar in both fracture faces with 1200-1300 particles·μm(-2). ... | 1988 | 24221484 |
| utilization of nitrate by bacteroids of bradyrhizobium japonicum in the soybean root nodule. | bacteroids of bradyrhizobium japonicum strain cb1809, unlike cc705, do not have a high level of constitutive nitrate reductase (nr; ec 1.7.99.4) in the soybean (glycine max. merr.) nodule. ex planta both strains have a high activity of nr when cultured on 5 mm nitrate at 2% o2 (v/v). nitrite reductase (nir) was active in cultured cells of bradyrhizobia, but activity with succinate as electron donor was not detected in freshly-isolated bacteroids. a low activity was measured with reduced methyl v ... | 1988 | 24221417 |
| nodulin gene expression during soybean (glycine max) nodule development. | in vitro translation products of total rna isolated from soybean nodules at successive stages of nodule development were analyzed by two-dimensional gel electrophoresis. in that way the occurrence of over 20 mrnas specifically transcribed from nodulin genes was detected. the nodulin genes could be divided into two classes according to the time of expression during nodule development. class a comprises at least 4 nodulin mrnas which are found when a globular meristem is present in the root cortex ... | 1987 | 24301261 |
| a block in the endocytosis of rhizobium allows cellular differentiation in nodules but affects the expression of some peribacteroid membrane nodulins. | a transposon-induced mutant (t8-1) of bradyrhizobium japonicum (61a76) was unable to develop into the nitrogen-fixing endosymbiotic form, the bacteroid. comparison between this mutant and t5-95, an ineffective (non-nitrogen fixing, fix(-)) mutant, confirmed that the process of bacteroid development is a distinct phase of differentiation of the endosymbiont and is independent of nitrogen fixation activity. the t8-1 mutant was able to induce normal-size nodules which differentiated two plant cell ... | 1987 | 24276967 |
| a vector for the site-directed, genomic integration of foreign dna into soybean root-nodule bacteria. | a non-essential dna region carrying two different repeated sequences (rsβ3 and rsα9) adjacent to a nitrogen fixation (nif) gene cluster has been identified previously in bradyrhizobium japonicum strain 110. in closely related b. japonicum strains a similar genomic arrangement was found. we constructed a mobilizable plasmid vector carrying rsβ3 and rsα9, and a kanamycin resistance cassette (nptii gene) plus suitable cloning sites inserted between the two repeated sequences. using this vector (prj ... | 1987 | 24276796 |
| expression of nodule-specific glutamine synthetase genes during nodule development in soybeans. | a cdna clone (pcpvngs-01) to glutamine synthetase (gs) mrna from root nodules of phaseolus vulgaris showed cross-hybridization to gs and mrna from soybean root nodules, thus allowing its use as a probe to study the expression of gs genes during root nodule development in soybeans. hybrid-select translation of root and nodule rna of soybean with dna from pcpvngs-01, followed by 2d gel electrophoresis, showed six peptides in the root and an additional four peptides in the nodule which represent no ... | 1986 | 24302304 |
| immunogold localization of nodule-specific uricase in developing soybean root nodules. | immunogold labeling was used to study the time of appearance and distribution of a nodule-specific form of uricase (ec 1.7.3.3) in developing nodules of soybean (glycine max (l.) merr.) inoculated with bradyrhizobium japonicum. the enzyme was detected in thin sections of tissue embedded in either l r white acrylic resin or spurr's epoxy resin, by employing a polyclonal antibody preparation active against a subunit of soybean nodule uricase. antigenicity was better preserved in l r white resin, b ... | 1986 | 24240357 |
| spatial relationships between uninfected and infected cells in root nodules of soybean. | in soybean (glycine max (l.) merr.) the uninfected cells of the root nodule are responsible for the final steps in ureide production from recently fixed nitrogen. stereological methods and an original quantitative method were used to investigate the organization of these cells and their spatial relationships to infected cells in the central region of nodules of soybean inoculated with rhizobium japonicum strain usda 3i1b110 and grown with and without nitrogen (as nitrate) in the nutrient medium. ... | 1985 | 24241217 |
| ultrastructure of infection-thread development during the infection of soybean by rhizobium japonicum. | the location and topography of infection sites in soybean (glycine max (l.) merr.) root hairs spot-inoculated with rhizobium japonicum have been studied at the ultrastructural level. infections commonly developed at sites created when the induced deformation of an emerging root hair caused a portion of the root-hair cell wall to press against an adjacent epidermal cell, entrapping rhizobia within the pocket between the two host cells. infections were initiated by bacteria which became embedded i ... | 1985 | 24249405 |
| lysis of bacterioids in the vicinity of the host cell nucleus in an ineffective (fix(-)) root nodule of soybean (glycine max). | in nodules of glycine max cv. mandarin infected with a nod (+)fix(-) mutant of rhizobium japonicum (rh 31-marburg), lysis of bacteroids was observed 20 d after infection, but occurred in the region around the host cell nucleus, where lytic compartments were formed. bacteroids, and peribacteroid membranes in other parts of the host cell remained stable until senescence (40d after infection). with two other nod(+) fix(-) mutants of r. japonicum either stable bacteroids and peribacteroid membranes ... | 1984 | 24253941 |
| insertion and deletion mutations within the nif region of rhizobium japonicum. | insertion and deletion mutants were used to characterize a genomic region of rhizobium japonicum where the nitrogenase structural genes are located on two separate operons nifdk and nifh. in addition to previously described nifd:: tn5 and nifk:: tn5 mutations we have now generated, by localized mutagenesis, further tn5 insertion mutations in the vicinity of nifdk as well as within and adjacent to nifh. the nifd:: tn5, nifk:: tn5, and nifh:: tn5 mutant strains were of the nod(+) fix(-) phenotype ... | 1984 | 24310349 |
| glutamine synthetase, glutamate synthase and glutamate dehydrogenase in rhizobium japonicum strains grown in cultures and in bacteroids from root nodules of glycine max. | the growth yields of three strains of rhizobium japonicum (cb 1809, cc 723, cc 705) in culture solutions containing l-glutamate were about twice those grown with ammonium. the activities of glutamine synthetase (gs; ec 6.3.1.2) and glutamate dehydrogenase (gdh; ec 1.4.1.4) were dependent on the nitrogen source in the medium and also varied with growth. both nadph-and nadh-dependent glutamate synthase (gogat; ec 1.4.1.13) and nadph-dependent gdh were found in strains grown with either glutamate o ... | 1983 | 24258169 |
| lectin in five soybean cultivars previously considered to be lectin-negative. | hemagglutinating proteins were isolated by affinity chromatography from seeds of each of five cultivars of soybeans (clycine max (l.) merr.) previously reported to lack detectable lectin (s.p. pull et al., 1978; science 200, 1277). quantities were between 1,000 and 10,000 times less than that found in the seeds of the reference cultivar, chippewa. the sensitivity of the hemagglutinating assay was 0.05 μg ml(-1). hemagglutinating activity was demonstrated in affinity-purified fractions from bulk ... | 1983 | 24264541 |
| nodulation of soybean byrhizobium japonicum mutants with altered capsule synthesis. | spontaneous mutants with altered capsule synthesis were isolated from a marked strain of the symbiont,rhizobium japonicum. differential centrifugation was used to enrich serially for mutants incapable of forming capsules. the desired mutants were detected by altered colony morphology and altered ability to bind host plant lectin. three mutants failed to form detectable capsules at any growth phase when cultured in vitro or in association with the host (soybean,glycine max (l.) merr.) roots. thes ... | 1982 | 24275968 |
| development of nodules of glycine max infected with an ineffective strain of rhizobium japonicum. | bacteroids in ineffective (nitrogenase negative) nodules of glycine max, infected with rhizobium japonicum 61-a-24, as compared to those in effective nodules are characterized by reduced specific activities of alanine dehydrogenase to 15%, of 3-hydroxybutyrate dehydrogenase to 50%, and an increase of glutamine synthetase to 400%. in the plant cytoplasm of ineffective nodules, glutamine synthetase activity is reduced to 10-30%, glutamate dehydrogenase to 50-70%, and the aspartate aminotransferase ... | 1980 | 24311082 |
| differentiation of nodules of glycine max : ultrastructural studies of plant cells and bacteroids. | plants of glycine max var. caloria, infected as 14 d old seedlings with a defined titre of rhizobium japonicum 3il b85 in a 10 min inoculation test, develop a sharp maximum of nitrogenase activity between 17 and 25 d after infection. this maximum (14±3 nmol c2h4 h(-1) mg nodule fresh weight(-1)), expressed as per mg nodule or per plant is followed by a 15 d period of reduced nitrogen fixation (20-30% of peak activity). 11 d after infection the first bacteroids develop as single cells inside infe ... | 1978 | 24414773 |
| viability of rhizobium bacteroids isolated from soybean nodule protoplasts. | bacteriods isolated from protoplasts taken from rhizobium japonicum induced root nodule of glycine max l. showed complete viability when plated onto a conventional rhizobial growth medium supplemented with 0.2 m mannitol. the same medium but without extra mannitol resulted in the absence of colony formation. the protoplast isolation method eliminated the possibility of contaminant bacteria from infection threads to be scored. the redifferentiated bacteroid clones have the same genetical characte ... | 1978 | 24408197 |