| photosynthetic symbionts of aeschynomene spp. form a cluster with bradyrhizobia on the basis of fatty acid and rrna analyses. | the relationship between photosynthetic rhizobia that nodulate 10 aeschynomene species (aeschynomene afraspera, aeschynomene denticulata, aeschynomene evenia, aeschynomene indica, aeschynomene nilotica, aeschynomene pratensis, aeschynomene rudis, aeschynomene scabra, aeschynomene schimperi, and aeschynomene sensitiva) and reference strains of the genera bradyrhizobium, rhizobium, and azorhizobium was investigated by analyzing cellular fatty acid methyl esters (fame) and 16s rrna sequences. the m ... | 1994 | 7520731 |
| phenotypic and genotypic characterization of bradyrhizobia nodulating the leguminous tree acacia albida. | rhizobial isolates that were obtained from both surface and deep soil samples in the sahelian and sudano-guinean areas of senegal (west africa) under acacia albida trees were compared with representative strains of known rhizobial species and genera. sodium dodecyl sulfate-polyacrylamide gel electrophoresis (sds-page) of proteins was used to determine the taxonomic positions of these organisms and the relationships between isolates obtained from the surface and isolates obtained from deep soil. ... | 1994 | 7520737 |
| bradyrhizobium elkanii lipo-oligosaccharide signals induce complete nodule structures on glycine soja siebold et zucc. | | 1994 | 7764873 |
| dna sequence of the common nodulation genes of bradyrhizobium elkanii and their phylogenetic relationship to those of other nodulating bacteria. | a 6.6-kb bamhi fragment containing the common nodulation genes of bradyrhizobium elkanii usda94 was identified by southern hybridization using the common nod genes of b. japonicum as a probe. this fragment was cloned and sequenced. analysis of the sequence showed open reading frames highly homologous to nola, nodd2, nodd1, and nodkabc from other bradyrhizobial sources. the sequence showed higher homology to the common nod genes of bradyrhizobium sp. (parasponia) than to those from b. japonicum. ... | 1994 | 7949325 |
| common soybean inoculant strains in brazil are members of bradyrhizobium elkanii. | the brazilian inoculant strains 29w and 587 were found to be members of bradyrhizobium elkanii primarily on the basis of 16s rrna gene sequences identical to that of b. elkanii usda76 and on the basis of reactivity with antibodies against serogroups 76 and 31, respectively. the agronomic consequences of using strains of b. elkanii as soybean inoculants are discussed. | 1993 | 8285723 |
| bradyrhizobium (arachis) sp. strain nc92 contains two nodd genes involved in the repression of noda and a nola gene required for the efficient nodulation of host plants. | the common nodulation locus and closely linked nodulation genes of bradyrhizobium (arachis) sp. strain nc92 have been isolated on an 11.0-kb ecori restriction fragment. the nucleotide sequence of a 7.0-kb ecorv-ecori subclone was determined and found to contain open reading frames (orfs) homologous to the noda, nodb, nodd1, nodd2, and nola genes of bradyrhizobium japonicum and bradyrhizobium elkanii. nodulation assays of nodd1, nodd2, or nola deletion mutants on the host plants macroptilium atro ... | 1996 | 8631662 |
| genetic diversity among bradyrhizobium isolates that effectively nodulate peanut (arachis hypogaea). | symbiotic gene diversity and other measures of genetic diversity were examined in bradyrhizobium isolates that form an effective symbiosis with peanut (arachis hypogaea). initially, restriction fragment length polymorphism (rflp) analysis using a nitrogenase (nif) gene probe was performed on 33 isolates along with one bradyrhizobium elkanii and two bradyrhizobium japonicum strains. considerable diversity was observed among the rflp patterns of many of the isolates, especially those from south am ... | 1996 | 8941988 |
| genetic variability of the common nod gene in soybean bradyrhizobia isolated in thailand and japan. | to determine the taxonomic relationship between thai soybean bradyrhizobia and soybean bradyrhizobia from other regions, a total of 62 bradyrhizobium strains were isolated in thailand. the genetic diversity of the strains was examined with reference to 46 japanese and 15 usda strains. the degree of sequence divergence in and around common nod gene regions of the 123 strains was estimated by restriction fragment length polymorphism analysis using the bradyrhizobium japonicum usda 110 common noddy ... | 1996 | 8989861 |
| genetic diversity of rhizobial symbionts isolated from legume species within the genera astragalus, oxytropis, and onobrychis. | the genetic diversity of 44 rhizobial isolates from astragalus, oxytropis, and onobrychis spp. originating from different geographic locations was evaluated by mapped restriction site polymorphism (mrsp) analysis of 16s rrna genes and by pcr dna fingerprinting with repetitive sequences (rep-pcr). a comparison of tree topologies of reference strains constructed with data obtained by mrsp and by 16s rrna gene sequence analyses showed that the topologies were in good agreement, indicating that the ... | 1997 | 9406393 |
| new assay for rhizobitoxine based on inhibition of 1-aminocyclopropane-1-carboxylate synthase. | rhizobitoxine is synthesized by the legume symbiont bradyrhizobium elkanii and the plant pathogen burkholderia andropogonis. rhizobitoxine competitively inhibited 1-aminocyclopropane-1-carboxylate (acc) synthase ble-acs2 from the tomato, a key enzyme in the pathway of ethylene biosynthesis. based on this inhibition of acc synthase, we have developed a new assay for rhizobitoxine. | 1999 | 9925628 |
| photosynthetic bradyrhizobia from aeschynomene spp. are specific to stem-nodulated species and form a separate 16s ribosomal dna restriction fragment length polymorphism group. | we obtained nine bacterial isolates from root or collar nodules of the non-stem-nodulated aeschynomene species a. elaphroxylon, a. uniflora, or a. schimperi and 69 root or stem nodule isolates from the stem-nodulated aeschynomene species a. afraspera, a. ciliata, a. indica, a. nilotica, a. sensitiva, and a. tambacoundensis from various places in senegal. these isolates, together with 45 previous isolates from various aeschynomene species, were studied for host-specific nodulation within the genu ... | 1999 | 10388707 |
| aberrant nodulation response of vigna umbellata to a bradyrhizobium japonicum nodz mutant and nodulation signals. | the (brady)rhizobium nodulation gene products synthesize lipo-chitin oligosaccharide (lco) signal molecules that induce nodule primordia on legume roots. in spot inoculation assays with roots of vigna umbellata, bradyrhizobium elkanii lco and chemically synthesized lco induced aberrant nodule structures, similar to the activity of these lcos on glycine soja (soybean). lcos containing a pentameric chitin backbone and a reducing-end 2-o-methyl fucosyl moiety were active on v. umbellata. in contras ... | 1999 | 10494629 |
| phylogenetic analyses of bradyrhizobium strains nodulating soybean (glycine max) in thailand with reference to the usda strains of bradyrhizobium. | to elucidate the phylogenetic relationships between thai soybean bradyrhizobia and usda strains of bradyrhizobium, restriction fragment length polymorphism (rflp) analysis using the nifdk gene probe and sequencing of the partial 16s rrna gene were performed. in our previous work, thai isolates of bradyrhizobium sp. (glycine max) were separated clearly from bradyrhizobium japonicum and bradyrhizobium elkanii based on the rflp analysis using the noddyabc gene probe. rflp analysis using the nifdk g ... | 1999 | 10528395 |
| relationships of bradyrhizobia from the legumes apios americana and desmodium glutinosum. | multilocus enzyme electrophoresis, partial 23s rrna sequences, and nearly full-length 16s rrna sequences all indicated high genetic similarity among root-nodule bacteria associated with apios americana, desmodium glutinosum, and amphicarpaea bracteata, three common herbaceous legumes whose native geographic ranges in eastern north america overlap extensively. a total of 19 distinct multilocus genotypes (electrophoretic types [ets]) were found among the 35 a. americana and 33 d. glutinosum isolat ... | 1999 | 10543803 |
| analysis of cellular fatty acids and phenotypic relationships of agrobacterium, bradyrhizobium, mesorhizobium, rhizobium and sinorhizobium species using the sherlock microbial identification system. | previous studies have demonstrated that cellular fatty acid analysis is a useful tool for identifying unknown strains of rhizobia and establishing taxonomic relationships between the species. in this study, the fatty acid profiles of over 600 strains belonging to the genera agrobacterium, bradyrhizobium, mesorhizobium, rhizobium and sinorhizobium were evaluated using the gaschromatography-based sherlock microbial identification system (mis). data collected with the mis showed that the three phyl ... | 2000 | 10758890 |
| bradyrhizobium spp. (tgx) isolates nodulating the new soybean cultivars in africa are diverse and distinct from bradyrhizobia that nodulate north american soybeans. | the newly developed cultivars of soybean in africa, known as tropical glycine cross (tgx), are nodulated by bradyrhizobia indigenous to african soils, here designated bradyrhizobium spp. (tgx). isolates of bradyrhizobium spp. (tgx) obtained from nodules of tgx soybeans that were inoculated with soils from 65 locations in six african countries were characterized and grouped into 11 phylogenetic clusters on the basis of rflp of the 16s rrna gene. five restriction enzymes (rsai, hinfi, mspi, cfoi a ... | 2000 | 10826808 |
| rhizobitoxine production by bradyrhizobium elkanii enhances nodulation and competitiveness on macroptilium atropurpureum. | application of 1-aminoocyclopropane-1-carboxylic acid, an ethylene precursor, decreased nodulation of macroptilium atropurpureum by bradyrhizobium elkanii. b. elkanii produces rhizobitoxine, an ethylene synthesis inhibitor. elimination of rhizobitoxine production in b. elkanii increased ethylene evolution and decreased nodulation and competitiveness on m. atropurpureum. these results suggest that rhizobitoxine enhances nodulation and competitiveness of b. elkanii on m. atropurpureum. | 2000 | 10831453 |
| relationships of bradyrhizobia from platypodium and machaerium (papilionoideae: tribe dalbergieae) on barro colorado island, panama. | enzyme electrophoresis and rrna sequencing indicated that root nodule bacteria from the canopy tree platypodium elegans and the lianas machaerium milleflorum and machaerium arboreum on barro colorado island, panama, were highly diverse on a local scale. a total of 11 distinct multilocus genotypes [ets (electrophoretic types)] was found among the 33 isolates analysed. on average, ets differed from one another at 74% of the 11 enzyme loci assayed, and separate nodules on a single host individual w ... | 2000 | 10843061 |
| aflp fingerprint analysis of bradyrhizobium strains isolated from faidherbia albida and aeschynomene species. | the diversity of bradyrhizobium isolates from faidherbia albida and aeschynomenee species was assessed using aflp analysis, a high-resolution genomic fingerprinting technique. reference strains from bradyrhizobium japonicum, bradyrhizobium elkanii and bradyrhizobium liaoningense were included for comparison. at a similarity level of 50%, a total of 34 different groups were obtained by cluster analysis of the genomic fingerprints. four of these clusters correspond to the three reference species, ... | 2000 | 10879988 |
| isolation and characterization of low-indole-3-acetic acid-producing mutants from bradyrhizobium elkanii. | we isolated 11 low-indole-3-acetic acid (iaa)-producing mutants of bradyrhizobium elkanii by tn5 mutagenesis. the amount of iaa produced by each mutant was 2.2-13.6% of that of the wild-type. it was found by resting cell reactions that the biosynthetic step to convert indole-3-pyruvic acid to indole-3-acetaldehyde was blocked in all the mutants. | 2000 | 10945251 |
| genetic characterization of soybean rhizobia in paraguay. | the soybean is an exotic plant introduced in paraguay in this century; commercial cropping expanded after the 1970s. inoculation is practiced in just 15 to 20% of the cropping areas, but root nodulation occurs in most sites where soybeans grow. little is known about rhizobial diversity in south america, and no study has been performed in paraguay until this time. therefore, in this study, the molecular characterization of 78 rhizobial isolates from soybean root nodules, collected under field con ... | 2000 | 11055970 |
| evolutionary relationships among the soybean bradyrhizobia reconstructed from 16s rrna gene and internally transcribed spacer region sequence divergence. | from sequence divergence of 16s rrna genes and the internally transcribed spacer (its) region it is reported that variation in phylogenetic placement exists among the 17 different serotype strains of bradyrhizobium that have been isolated from nodules of soybean. evolutionary relationships among the bradyrhizobia were more resolved using reconstructions derived from its than from 16s rrna gene sequence divergence. strain usda 129 was placed together with usda 62, 110, 122 and 126, but did not cl ... | 2000 | 11155993 |
| phylogenetic and dna-dna hybridization analyses of bradyrhizobium species. | the 16s rdna sequence of bradyrhizobium liaoningense was determined and analysed together with sequences of other bradyrhizobium species and related taxa. in addition, dna-dna hybridizations were performed between representative strains of the three bradyrhizobium species. bradyrhizobium liaoningense is genotypically highly related to bradyrhizobium japonicum, whereas bradyrhizobium elkanii is more distantly related to these two species. the fact that afipia, agromonas, blastobacter, nitrobacter ... | 2001 | 11211247 |
| case of localized recombination in 23s rrna genes from divergent bradyrhizobium lineages associated with neotropical legumes. | enzyme electrophoresis and rrna sequencing were used to analyze relationships of bradyrhizobium sp. nodule bacteria from four papilionoid legumes (clitoria javitensis, erythrina costaricensis, rhynchosia pyramidalis, and desmodium axillare) growing on barro colorado island (bci), panama. bacteria with identical multilocus allele profiles were commonly found in association with two or more legume genera. among the 16 multilocus genotypes (electrophoretic types [ets]) detected, six ets formed a cl ... | 2001 | 11319084 |
| comparison of sequence analysis of 16s-23s rdna spacer regions, aflp analysis and dna-dna hybridizations in bradyrhizobium. | the sequences of the 16s-23s rdna intergenic spacer region of 62 strains of bradyrhizobium, including representatives of the three valid species, were determined. the majority of strains had a single rrna operon type and all contained a trna(ala) and a trna(ile) gene. analysis of the sequence data produced groupings in line with previously obtained aflp data. dna-dna hybridizations were performed to determine to what extent spacer sequences and aflp profiles reflected the overall genomic similar ... | 2001 | 11321108 |
| ribotyping of rhizobia nodulating acacia mangium and paraserianthes falcataria from different geographical areas in indonesia using pcr-rflp-sscp (prs) and sequencing. | acacia mangium and paraserianthes falcataria are leguminous tree species widely grown for timber in indonesia and other tropical countries, yet little is known about the identity of their rhizobial symbionts. polymerase chain reaction-restriction fragment length polymorphism-single-strand conformational polymorphism (prs) analysis of the 16s rrna gene was used along with sequencing to assess the diversity of 57 rhizobia isolated from nodules of a. mangium and p. falctaria in indonesia. in total, ... | 2001 | 11359513 |
| changes in fatty acid composition and degree of unsaturation of (brady)rhizobia as a response to phases of growth, reduced water activities and mild desiccation. | the effects of growth phase, reductions in the water activity (a(w)) of the growth medium and mild desiccation on the composition and the degree of unsaturation of cellular fatty acids (cfa) of sinorhizobium meliloti, bradyrhizobium elkanii and bradyrhizobium japonicum were studied. during the course of growth, an interchange of cis-vaccenic with lactobacillic acid and a slight increase in palmitic acid were observed while other fatty acids remained constant. the degree of unsaturation was signi ... | 2001 | 11392487 |
| determination of the chemical structure of the capsular polysaccharide of strain b33, a fast-growing soya bean-nodulating bacterium isolated from an arid region of china. | we have determined the structure of a polysaccharide from strain b33, a fast-growing bacterium that forms nitrogen-fixing nodules with asiatic and american soya bean cultivars. on the basis of monosaccharide analysis, methylation analysis, one-dimensional 1h- and 13c-nmr and two-dimensional nmr experiments, the structure was shown to consist of a polymer having the repeating unit -->6)-4-o-methyl-alpha-d-glcp-(1-->4)-3-o-methyl-beta-d-glcpa-(1--> (where glcpa is glucopyranuronic acid and glcp is ... | 2001 | 11439101 |
| characterization of soybean bradyrhizobia for which serogroup affinities have not been identified. | the usda, ars national rhizobium germplasm collection contains 143 accessions of slow-growing soybean strains among which there are 17 distinct serological groups. however, 11 strains appear to have no serological affinity with the 17 serogroups. therefore, we determined whether these strains were diverse and examined their phylogenetic placement. nine strains formed nitrogen-fixing symbioses with soybean indicating that these accessions were not contaminants. we concluded from results of amplif ... | 2001 | 11467727 |
| specific detection of bradyrhizobium and rhizobium strains colonizing rice (oryza sativa) roots by 16s-23s ribosomal dna intergenic spacer-targeted pcr. | in addition to forming symbiotic nodules on legumes, rhizobial strains are members of soil or rhizosphere communities or occur as endophytes, e.g., in rice. two rhizobial strains which have been isolated from root nodules of the aquatic legumes aeschynomene fluminensis (irbg271) and sesbania aculeata (irbg74) were previously found to promote rice growth. in addition to analyzing their phylogenetic positions, we assessed the suitability of the 16s-23s ribosomal dna (rdna) intergenic spacer (igs) ... | 2001 | 11472944 |
| dna-dna hybridization study of bradyrhizobium strains. | dna-dna hybridizations were performed between bradyrhizobium strains, isolated mainly from faidherbia albida and aeschynomene species, as well as bradyrhizobium reference strains. results indicated that the genus bradyrhizobium consists of at least 11 genospecies, i to xi. the genospecies formed four subgeneric groups that were more closely related to each other (>40% dna hybridization) than to other genospecies (<40% dna hybridization): (i) genospecies i (bradyrhizobium japonicum), iii (bradyrh ... | 2001 | 11491327 |
| dna sequence and mutational analysis of rhizobitoxine biosynthesis genes in bradyrhizobium elkanii. | we cloned and sequenced a cluster of genes involved in the biosynthesis of rhizobitoxine, a nodulation enhancer produced by bradyrhizobium elkanii. the nucleotide sequence of the cloned 28.4-kb dna region encompassing rtxa showed that several open reading frames (orfs) were located downstream of rtxa. a large-deletion mutant of b. elkanii, usda94 delta rtx::omega 1, which lacks rtxa, orf1 (rtxc), orf2, and orf3, did not produce rhizobitoxine, dihydrorhizobitoxine, or serinol. the broad-host-rang ... | 2001 | 11679318 |
| rhizobitoxine production and symbiotic compatibility of bradyrhizobium from asian and north american lineages of amphicarpaea. | reciprocal inoculations with bradyrhizobium sp. isolates from the north american legume amphicarpaea bracteata (l.) fern. (phaseoleae-glycininae) and from a japanese population of its close relative amphicarpaea edgeworthii (benth.) var. japonica were performed to analyze relative symbiotic compatibility. amphicarpaea edgeworthii plants formed few or no nodules with any north american bradyrhizobial strains isolated from a. bracteata, but all a. bracteata lineages formed effective nitrogen-fixin ... | 2001 | 11718541 |
| bradyrhizobia from wild phaseolus, desmodium, and macroptilium species in northern mexico. | rrna genetic markers were analyzed in 97 isolates of nodule bacteria from six legume species in chihuahua, mexico. the most common genotypes were widely shared across host species and had 16s rrna sequences identical to those of strains from an eastern north american legume (amphicarpaea) that are closely related to bradyrhizobium elkanii. | 2002 | 11916730 |
| conflicting phylogeographic patterns in rrna and nifd indicate regionally restricted gene transfer in bradyrhizobium. | major differences in evolutionary relationships of the 16s rrna gene and the nitrogenase alpha-subunit gene (nifd) were observed among 38 strains of bradyrhizobium sp. nodule bacteria from north america, central america, asia and australia. two lineages were evident in the 16s rrna phylogeny representing strains related to bradyrhizobium japonicum (29 isolates) or bradyrhizobium elkanii (9 isolates). both clades were distributed across most or all of the geographic regions sampled. by contrast, ... | 2002 | 12177349 |
| analysis of genomic diversity among photosynthetic stem-nodulating rhizobial strains from northeast argentina. | the genomic diversity among photosynthetic rhizobia from northeast argentina was assessed. forty six isolates obtained from naturally occurring stem and root nodules of aeschynomene rudis plants were analyzed by three molecular typing methods with different levels of taxonomic resolution: repetitive sequence-based pcr (rep-pcr) genomic fingerprinting with box and rep primers, amplified 16s rdna restriction analysis (ardra), and 16s-23s rdna intergenic spacer-restriction fragment length polymorph ... | 2002 | 12421080 |
| partial 16s rrna gene sequence diversity and numerical taxonomy of slow growing pigeonpea (cajanus cajan l millsp) nodulating rhizobia. | an investigation was carried out to determine the diversity of 30 isolates of slow growing pigeonpea nodulating rhizobia based on variations in partial sequences of the 16s rrna gene and numerical analysis of 80 phenotypic traits. phylogenetic analysis using molecular sequences of 23 isolates showed that arpe1 separated from the other isolates at an average distance of >14% divergence level. the other isolates were all within 5% divergence from each other but separated into four main groups, wit ... | 2002 | 12435494 |
| characterization of rhizobia that nodulate legume species of the genus lespedeza and description of bradyrhizobium yuanmingense sp. nov. | legume species belonging to the genus lespedeza are annual or perennial herb or shrub plants that grow in the northern hemisphere. they are known for the formation of root nodules, but little information is available about their microsymbionts. in this study, 58 root-nodule isolates from lespedeza spp., obtained from china and the usa, were characterized using numerical taxonomic analysis of phenotypic features, sds-page analysis of whole-cell proteins, dna-dna hybridization, 16s rrna gene seque ... | 2002 | 12508891 |
| rrna and nifd phylogeny of bradyrhizobium from sites across the pacific basin. | many undomesticated legumes harbor nodule bacteria related to the soybean symbiont bradyrhizobium elkanii, but little is known about their phylogenetic relationships or geographic distribution. sequences of ribosomal genes (16s rrna and partial 23s rrna) and the nitrogenase alpha-subunit gene (nifd) were analyzed in 22 isolates of this group sampled from diverse legumes in korea, japan, the usa, mexico, costa rica and panama. some strains from asia and north america shared identical sequences fo ... | 2003 | 12620615 |
| bradyrhizobium elkanii rtxc gene is required for expression of symbiotic phenotypes in the final step of rhizobitoxine biosynthesis. | we disrupted the rtxc gene on the chromosome of bradyrhizobium elkanii usda94 by insertion of a nonpolar aph cartridge. the rtxc mutant, designated deltartxc, produced serinol and dihydrorhizobitoxine but no rhizobitoxine, both in culture and in planta. the introduction of cosmids harboring the rtxc gene into the deltartxc mutant complemented rhizobitoxine production, suggesting that rtxc is involved in the final step of rhizobitoxine biosynthesis in b. elkanii usda94. glycine max cv. lee inocul ... | 2004 | 14711685 |
| root nodule bradyrhizobium spp. harbor tfdaalpha and cada, homologous with genes encoding 2,4-dichlorophenoxyacetic acid-degrading proteins. | the distribution of tfdaalpha and cada, genes encoding 2,4-dichlorophenoxyacetate (2,4-d)-degrading proteins which are characteristic of the 2,4-d-degrading bradyrhizobium sp. isolated from pristine environments, was examined by pcr and southern hybridization in several bradyrhizobium strains including type strains of bradyrhizobium japonicum usda110 and bradyrhizobium elkanii usda94, in phylogenetically closely related agromonas oligotrophica and rhodopseudomonas palustris, and in 2,4-d-degradi ... | 2004 | 15066803 |
| effect of soil bradyrhizobia on the success of soybean inoculant strain cb 1809. | four decades of soybean [glycine max (l.) merr.] cultivation in south africa has resulted in the establishment of populations of bradyrhizobia against which the recently introduced inoculant strain cb 1809 must compete. serological and dna fingerprinting methods were used to study the diversity of nodule isolates from soils at bergville, koedoeskop and morgenzon. dominant serogroups included bradyrhizobium elkanii serotype 76 at bergville (67%), bradyrhizobium japonicum serotype 123 at morgenzon ... | 2004 | 15462522 |
| detection of homoserine lactone-like quorum sensing molecules in bradyrhizobium strains. | one hundred and forty-two bradyrhizobium strains were screened for their ability to produce n-acyl homoserine lactone-like molecules (ahls) by using an agrobacterium tumefaciens biosensor strain containing a trai-lacz fusion. approximately 22% (31 of 142) of the tested strains produced ahls that induced moderate to elevated beta-galactosidase activity levels in the biosensor strain. bradyrhizobium japonicum and bradyrhizobium elkanii strains were both shown to produce ahls. age of culture, and m ... | 2005 | 16132457 |
| a selective medium for the isolation and quantification of bradyrhizobium japonicum and bradyrhizobium elkanii strains from soils and inoculants. | the ecological examination of members of the family rhizobiaceae has been hampered by the lack of a selective medium for isolation of root nodule bacteria from soil. a novel non-antibiotic-containing medium has been developed which allows selective isolation of bradyrhizobium japonicum and b. elkanii strains from soil and inoculants. the medium, bjsm, is based on the resistance of b.japonicum and b. elkanii strains to more than 40 mug of the metals ions zn and co per ml. bjsm does not allow grow ... | 1994 | 16349188 |
| rflp analysis of the rrna operon of a brazilian collection of bradyrhizobial strains from 33 legume species. | genetic diversity in tropical rhizobial species is still poorly known. with the aim of increasing this knowledge, three ribosomal regions of 119 strains belonging to the official brazilian culture collection of rhizobia and classified as bradyrhizobium based on morphological and physiological characteristics in vitro were analysed by rflp-pcr. the strains were isolated from 33 legume species, representing nine tribes and all three subfamilies; they all form very effective n2-fixing nodules and 4 ... | 2006 | 16403890 |
| rhizobitoxine modulates plant-microbe interactions by ethylene inhibition. | bradyrhizobium elkanii produces rhizobitoxine, an enol-ether amino acid, which has been regarded as a phytotoxin because it causes chlorosis in soybeans. however, recent studies have revealed that rhizobitoxine plays a positive role in establishing symbiosis between b. elkanii and host legumes: rhizobitoxine enhances the nodulation process by inhibiting acc (1-aminocyclopropane-1-carboxylate) synthase in the ethylene biosynthesis of host roots. b. elkanii rtxa and rtxc genes are required for rhi ... | 2006 | 16516430 |
| variation in the nod gene rflps, nucleotide sequences of 16s rrna genes, nod factors, and nodulation abilities of bradyrhizobium strains isolated from thai vigna plants. | the analysis of nod genes and 16s rrna gene regions, nod factors, and nodulation abilities of brady rhizobium strains isolated from tropical thai vigna species is reported. a total of 55 bradyrhizobium strains isolated from two cultivated and six wild vigna species growing in central and northern thailand were evaluated. thai vigna spp. bradyrhizobium strains showed higher levels of nod gene rflp diversity compared with thai soybean brady rhizobium strains or temperate strains of bradyrhizobium ... | 2006 | 16541157 |
| bradyrhizobia isolated from root nodules of parasponia (ulmaceae) do not constitute a separate coherent lineage. | rhizobial bacteria almost exclusively nodulate members of the families fabaceae, mimosaceae and caesalpiniaceae, but are found on a single non-legume taxon, parasponia (ulmaceae). based on their host-range, their nitrogen-fixing ability and strain competition experiments, bacterial strains isolated from parasponia were thought to constitute a separate lineage that would account for their exceptional host affinity. this hypothesis was investigated by focusing on four isolates that are representat ... | 2006 | 16627647 |
| conservation of type iii secretion system genes in bradyrhizobium isolated from soybean. | the distribution of rhcrst genes encoding the type iii secretion system (t3ss) in a collection of bradyrhizobium strains was characterized by pcr and southern blot hybridization. the polymorphism of the corresponding sequences amplified by pcr was characterized by rflp and sequencing together with those available in the databank. genomic group i is characterized by the presence of bradyrhizobium elkanii strains and group ii by the presence of b. japonicum and b. liaoningense strains. highly cons ... | 2006 | 16734796 |
| bacterial diversity in aortic aneurysms determined by 16s ribosomal rna gene analysis. | aortic aneurysms are common vascular conditions that cause considerable morbidity and mortality. understanding of the mechanisms involved in the pathogenesis of the condition remains limited. recently, infection has been suggested as possible contributor in the development of the disease. the aim of the present study was to examine aortic aneurysms for the presence of bacterial dna using polymerase chain reaction (pcr) targeting the 16s ribosomal rna (rrna) gene, followed by cloning and sequenci ... | 2006 | 17098542 |
| rhizobitoxine production in agrobacterium tumefaciens c58 by bradyrhizobium elkanii rtxacdefg genes. | we examined the genetic basis and transfer for production of rhizobitoxine, an inhibitor of ethylene biosynthesis in plants, directed by the rtx genes of bradyrhizobium elkanii. comparison with genome sequences of bradyrhizobium japonicum and xanthomonas oryzae suggests that the rtx genes extend from the previously identified rtxac genes through four additional genes rtxdefg. reverse transcription-pcr analysis showed that the rtxacdefg genes are expressed as an operon. mutational analysis indica ... | 2007 | 17227467 |
| evidence of horizontal transfer of symbiotic genes from a bradyrhizobium japonicum inoculant strain to indigenous diazotrophs sinorhizobium (ensifer) fredii and bradyrhizobium elkanii in a brazilian savannah soil. | the importance of horizontal gene transfer (hgt) in the evolution and speciation of bacteria has been emphasized; however, most studies have focused on genes clustered in pathogenesis and very few on symbiosis islands. both soybean (glycine max [l.] merrill) and compatible bradyrhizobium japonicum and bradyrhizobium elkanii strains are exotic to brazil and have been massively introduced in the country since the early 1960s, occupying today about 45% of the cropped land. for the past 10 years, ou ... | 2007 | 17308185 |
| genetic diversity of rhizobia associated with desmodium species grown in china. | desmodia are leguminous plants used as important forage and herbal medicine in china. little information is available about the nodule bacteria of desmodium species. to understand the genetic diversity of rhizobia associated with desmodium species grown in china, isolates from temperate and subtropical regions were obtained and analysed. | 2007 | 17309506 |
| diversity and relationships of bradyrhizobia from legumes native to eastern north america. | dna sequencing and polymerase chain reaction (pcr) assays with lineage-specific primers were used to analyze the diversity of 276 isolates of bradyrhizobium sp. nodule bacteria associated with 13 native legumes species in the northeastern united states, representing eight genera in six legume tribes. a pcr screen with two primer pairs in the rrna region indicated that seven of the legume species were exclusively associated with strains having markers resembling bradyrhizobium elkanii, while the ... | 2006 | 17473884 |
| rhizobitoxine-induced chlorosis occurs in coincidence with methionine deficiency in soybeans. | rhizobitoxine, produced by the legume symbiont bradyrhizobium elkanii, inhibits cystathionine-beta-lyase (ec 4.4.1.8) in methionine biosynthesis and 1-aminocyclopropane-1-carboxylate synthase (acc) in ethylene biosynthesis. rhizobitoxine production by b. elkanii enhances nodulation of host legumes via the inhibition of ethylene synthesis, but causes foliar chlorosis in susceptible soybeans, though how it does so remains to be investigated. the aim of this study was to examine the physiological b ... | 2007 | 17525098 |
| insights learned from pbtai1, a 229-kb accessory plasmid from bradyrhizobium sp. strain btai1 and prevalence of accessory plasmids in other bradyrhizobium sp. strains. | in silico, physiological and in planta analyses were used to characterize pbtai1, a 229-kb accessory plasmid from bradyrhizobium sp. strain btai1, and assess its potential ecological function under free-living and symbiotic growth conditions. sequence analysis revealed the presence of an uptake hydrogenase system, a repabc family plasmid replication module and open reading frames encoding type iv secretion system, trai and trar autoinducer proteins and several copper resistance-related proteins. ... | 2008 | 18219284 |
| flavonoid-responsive nody-lacz expression in three phylogenetically different bradyrhizobium groups. | previously, restriction fragment length polymorphism analysis using the nodd1yabc gene probe showed the genetic diversity of common nodd1abc gene regions of bradyrhizobium japonicum, bradyrhizobium elkanii, and the thai soybean bradyrhizobium. the nodd1 sequences of representative strains of the 3 groups differed phylogenetically, suggesting that responses of nodd1 proteins of the 3 bradyrhizobium groups to diverse flavonoids may differ. to confirm this hypothesis, 6 representative strains were ... | 2008 | 18449225 |
| bradyrhizobium elkanii, bradyrhizobium yuanmingense and bradyrhizobium japonicum are the main rhizobia associated with vigna unguiculata and vigna radiata in the subtropical region of china. | cowpea (vigna unguiculata) and mung bean (vigna radiata) are important legume crops yet their rhizobia have not been well characterized. in the present study, 62 rhizobial strains isolated from the root nodules of these plants grown in the subtropical region of china were analyzed via a polyphasic approach. the results showed that 90% of the analyzed strains belonged to or were related to bradyrhizobium japonicum, bradyrhizobium liaoningense, bradyrhizobium yuanmingense and bradyrhizobium elkani ... | 2008 | 18564340 |
| retama species growing in different ecological-climatic areas of northeastern algeria have a narrow range of rhizobia that form a novel phylogenetic clade within the bradyrhizobium genus. | sixty-seven isolates were isolated from nodules collected on roots of mediterranean shrubby legumes retama raetam and retama sphaerocarpa growing in seven ecological-climatic areas of northeastern algeria. genetic diversity of the retama isolates was analyzed based on genotyping by restriction fragment length polymorphism of pcr-amplified fragments of the 16s rrna gene, the intergenic spacer (igs) region between the 16s and 23s rrna genes (igs), and the symbiotic genes nifh and nodc. eleven hapl ... | 2009 | 19231126 |
| genetic organization and functional analysis of the type iii secretion system of bradyrhizobium elkanii. | cloning and sequencing of a 47.1-kb chromosomal dna region revealed the presence of a type iii secretion system (t3ss) in bradyrhizobium elkanii usda61. the identified genes are likely to encode the transcriptional activator ttsi, core components of the secretion apparatus and secreted proteins. several orfs within the cluster are not conserved in other rhizobia. nine tts box motifs, a promoter element of ttsi-regulated genes, were found; six of them upstream of annotated genes. for functional a ... | 2009 | 19473255 |
| bradyrhizobium pachyrhizi sp. nov. and bradyrhizobium jicamae sp. nov., isolated from effective nodules of pachyrhizus erosus. | several strains isolated from the legume pachyrhizus erosus were characterized on the basis of diverse genetic, phenotypic and symbiotic approaches. these novel strains formed two groups closely related to bradyrhizobium elkanii according to their 16s rrna gene sequences. strains pac48t and pac68t, designated as the type strains of these two groups, presented 99.8 and 99.1% similarity, respectively, in their 16s rrna gene sequences with respect to b. elkanii usda 76t. in spite of these high simi ... | 2009 | 19567584 |
| phylogeny and taxonomy of a diverse collection of bradyrhizobium strains based on multilocus sequence analysis of the 16s rrna gene, its region and glnii, reca, atpd and dnak genes. | the genus bradyrhizobium encompasses a variety of bacteria that can live in symbiotic and endophytic associations with legumes and non-legumes, and are characterized by physiological and symbiotic versatility and broad geographical distribution. however, despite indications of great genetic variability within the genus, only eight species have been described, mainly because of the highly conserved nature of the 16s rrna gene. in this study, 169 strains isolated from 43 different legumes were ana ... | 2009 | 19628593 |
| quantitative and time-course evaluation of nodulation competitiveness of rhizobitoxine-producing bradyrhizobium elkanii. | abstract regression analysis of results from a mathematical competition model showed that rhizobitoxine production by bradyrhizobium elkanii usda94 gave this strain a nodulation competitiveness about 10 times greater than that of a non-rhizobitoxine-producing mutant strain on macroptilium atropurpureum (siratro). rhizobitoxine enhancement of competitive nodulation occurred at a late stage in the time-course of nodulation. all other known rhizobial factors that affect nodulation competitiveness a ... | 2003 | 19719626 |
| bradyrhizobia nodulating the acacia mangium x a. auriculiformis interspecific hybrid are specific and differ from those associated with both parental species. | in the context of an increasing utilization of the interspecific hybrid acacia mangium x a. auriculiformis as a plantation tree in the tropical humid zone, its symbiotic characterization was carried out in comparison with that of its two parental species. rhizobium strains of diverse geographical origins were isolated from root nodules of the hybrid and its parents. almost all acacia hybrid isolates were fast growing on yeast extract-mannitol medium, in contrast to those isolated from both paren ... | 2009 | 19854923 |
| the structure of a novel neutral lipid a from the lipopolysaccharide of bradyrhizobium elkanii containing three mannose units in the backbone. | the chemical structure of the lipid a of the lipopolysaccharide (lps) from bradyrhizobium elkanii usda 76 (a member of the group of slow-growing rhizobia) has been established. it differed considerably from lipids a of other gram-negative bacteria, in that it completely lacks negatively charged groups (phosphate or uronic acid residues); the glucosamine (glcpn) disaccharide backbone is replaced by one consisting of 2,3-dideoxy-2,3-diamino-d-glucopyranose (glcpn3n) and it contains two long-chain ... | 2010 | 20087912 |
| genetic diversity of native soybean bradyrhizobia from different topographical regions along the southern slopes of the himalayan mountains in nepal. | soybean-nodulating bradyrhizobia are genetically diverse and are classified into different species. in this study, the genetic diversity of native soybean bradyrhizobia isolated from different topographical regions along the southern slopes of the himalayan mountains in nepal was explored. soil samples were collected from three different topographical regions with contrasting climates. a local soybean cultivar, cobb, was used as a trap plant to isolate bradyrhizobia. a total of 24 isolates selec ... | 2010 | 20851547 |
| roles of flavonoids and the transcriptional regulator ttsi in the activation of the type iii secretion system of bradyrhizobium elkanii semia587. | bradyrhizobium elkanii semia587 is a symbiotic nitrogen-fixing bacterium of the group commonly called rhizobia, which induce nodule formation in legumes, and is widely used in brazilian commercial inoculants of soybean. in response to flavonoid compounds released by plant roots, besides nod factors, other molecular signals are secreted by rhizobia, such as proteins secreted by type iii secretion systems (t3sss). rhizobial t3sss are activated by the transcription regulator ttsi, which binds to se ... | 2010 | 21109563 |
| bradyrhizobium lablabi sp. nov., isolated from effective nodules of lablab purpureus and arachis hypogaea grown in southern china. | five strains isolated from root nodules of lablab purpureus and arachis hypogaea grown in anhui and sichuan provinces of china were classified within the genus bradyrhizobium. these strains had identical 16s rrna nucleotide sequences which shared 99.22% and 99.48% similarities with the most related strains of bradyrhizobium jicamae pac 68(t), bradyrhizobium pachyrhizi pac 48(t) and bradyrhizobium elkanii usda 76(t). polyphasic approaches including 16s rrna gene rflp, igs-rflp, box-pcr, comparati ... | 2010 | 21112989 |
| genetic diversity of nodulating and non-nodulating rhizobia associated with wild soybean (glycine soja sieb. & zucc.) in different ecoregions of china. | a total of 99 bacterial isolates that originated from root nodules of glycine soja were characterized with restriction analyses of amplified 16s ribosomal dna and 16s-23s rdna intergenic spacers (its), and sequence analyses of 16s rrna, rpob, atpd, reca and nodc genes. when tested for nodulation of g. soja, 72 of the isolates were effective symbionts, and these belonged to five species: bradyrhizobium japonicum, bradyrhizobium elkanii, bradyrhizobium yuanmingense, bradyrhizobium liaoningense and ... | 2011 | 21303397 |
| diversity and biogeography of rhizobia isolated from root nodules of glycine max grown in hebei province, china. | a total of 215 rhizobial strains were isolated and analyzed with 16s rrna gene, 16s-23s intergenic spacer, housekeeping genes atpd, reca, and glnii, and symbiotic genes nifh and nodc to understand the genetic diversity of soybean rhizobia in hebei province, china. all the strains except one were symbiotic bacteria classified into nine genospecies in the genera of bradyrhizobium and sinorhizobium. surveys on the distribution of these rhizobia in different regions showed that bradyrhizobium japoni ... | 2011 | 21340735 |
| phylogeny of nodulation and nitrogen-fixation genes in bradyrhizobium: supporting evidences for the theory of monophyletic origin and spread and maintenance by both horizontal and vertical transfer. | bacteria belonging to the genus bradyrhizobium are capable of establishing symbiotic relationships with a broad range of plants belonging to the three subfamilies of the leguminosae (=fabaceae) family, with the formation of specialized structures on the roots, the nodules, where fixation of atmospheric nitrogen takes place. the symbiosis is under the control of a finely tuned expression of common and host-specific nodulation genes and also of genes related to the assembly and activity of the nit ... | 2011 | 21357454 |
| phylogeny of bradyrhizobia from chinese cowpea miscellany inferred from 16s rrna, atpd, glnii, and 16s-23s intergenic spacer sequences. | the cowpea (vigna unguiculata l.), peanut (arachis hypogaea l.), and mung bean (vigna radiata l.) belong to a group of plants known as the "cowpea miscellany" plants, which are widely cultivated throughout the tropic and subtropical zones of africa and asia. however, the phylogeny of the rhizobial strains that nodulate these plants is poorly understood. previous studies have isolated a diversity of rhizobial strains from cowpea miscellany hosts and have suggested that, phylogenetically, they are ... | 2011 | 21491983 |
| genetic diversity of symbiotic bradyrhizobium elkanii populations recovered from inoculated and non-inoculated acacia mangium field trials in brazil. | acacia mangium is a legume tree native to australasia. since the eighties, it has been introduced into many tropical countries, especially in a context of industrial plantations. many field trials have been set up to test the effects of controlled inoculation with selected symbiotic bacteria versus natural colonization with indigenous strains. in the introduction areas, a. mangium trees spontaneously nodulate with local and often ineffective bacteria. when inoculated, the persistence of inoculan ... | 2011 | 21531520 |
| changes in population occupancy of bradyrhizobia under different temperature regimes. | to elucidate how temperature affects bradyrhizobial ecology, long-term incubations of bradyrhizobium japonicum usda 6(t), 38, and 123 and of bradyrhizobium elkanii usda 76(t) were conducted under various temperature conditions. proliferative traits in liquid culture and population occupancies in soil microcosms were compared. the occupancies of usda 76(t) and usda 123 in soil microcosms during long-term incubation changed with the temperature conditions. these results suggest that temperature is ... | 2010 | 21576887 |
| characterization of cyclic ╬▓-glucans of bradyrhizobium by maldi-tof mass spectrometry. | periplasmic, cyclic ╬▓-glucans isolated from bradyrhizobium elkanii, bradyrhizobium liaoningense, and bradyrhizobium yuanmingense strains have been investigated by means of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (maldi-tof ms), 1d and 2d nuclear magnetic resonance (nmr), as well as standard chemical methods. these compounds are built of 10-13 d-glucose residues. the main fractions contain molecules assembled of 12 hexose units (m(w)=1945.363da). glucose mono ... | 2011 | 21665197 |
| biodiversity and biogeography of rhizobia associated with soybean plants grown in the north china plain. | as the putative center of origin for soybean and the second largest region of soybean production in china, the north china plain covers temperate and subtropical regions with diverse soil characteristics. however, the soybean rhizobia in this plain have not been sufficiently studied. in order to investigate the biodiversity and biogeography of soybean rhizobia in this plain, a total of 309 isolates of symbiotic bacteria from the soybean nodules collected from 16 sampling sites were studied with ... | 2011 | 21784912 |
| biotechnological conversion of glycerol to 2-amino-1,3-propanediol (serinol) in recombinant escherichia coli. | microbial conversion is an important technology for the refinement of renewable resources. here, we describe the biotechnological conversion of glycerol to 2-amino-1,3-propanediol (serinol), a relevant intermediate in several chemical syntheses processes. either the dihydroxyacetone phosphate aminotransferase/dihydrorhizobitoxine synthase (rtxa) of bradyrhizobium elkanii usd94 or only the n-terminal domain (rtxa513) comprising the first reaction, respectively, was expressed in recombinant escher ... | 2011 | 21706173 |
| [genetic diversity and phylogeny of bradyrhizobia associated with desmodium spp]. | genetic diversity and phylogeny of bradyrhizobial strains associated with desmodium spp. in subtropic and temperate regions of china were analyzed. | 2011 | 22233051 |
| genetic variability in bradyrhizobium japonicum strains nodulating soybean [glycine max (l.) merrill]. | brazil has succeeded in sustaining production of soybean [glycine max (l.) merrill] by relying mainly on symbiotic n(2) fixation, thanks to the selection and use in inoculants of very effective strains of bradyrhizobium japonicum and bradyrhizobium elkanii. it is desirable that rhizobial strains used in inoculants have stable genetic and physiological traits, but experience confirms that rhizobial strains nodulating soybean often lose competitiveness in the field. in this study, soybean cultivar ... | 2011 | 22805968 |
| predominant nifh transcript phylotypes related to rhizobium rosettiformans in field-grown sugarcane plants and in norway spruce. | although some sugarcane cultivars may benefit substantially from biological nitrogen fixation (bnf), the responsible bacteria have been not identified yet. here, we examined the active diazotrophic bacterial community in sugarcane roots from africa and america by reverse transcription (rt)-pcr using broad-range nifh-specific primers. denaturing gradient gel electrophoresis (dgge) profiles obtained from sugarcane showed a low diversity at all sample locations with one phylotype amounting up to 10 ... | 2011 | 23761284 |
| application of representational difference analysis to identify genomic differences between bradyrhizobium elkanii and b. japonicum species. | bradyrhizobium elkanii is successfully used in the formulation of commercial inoculants and, together with b. japonicum, it fully supplies the plant nitrogen demands. despite the similarity between b. japonicum and b. elkanii species, several works demonstrated genetic and physiological differences between them. in this work representational difference analysis (rda) was used for genomic comparison between b. elkanii semia 587, a crop inoculant strain, and b. japonicum usda 110, a reference stra ... | 2010 | 24031597 |
| identification of bradyrhizobium elkanii genes involved in incompatibility with soybean plants carrying the rj4 allele. | symbioses between leguminous plants and soil bacteria known as rhizobia are of great importance to agricultural production and nitrogen cycling. while these mutualistic symbioses can involve a wide range of rhizobia, some legumes exhibit incompatibility with specific strains, resulting in ineffective nodulation. the formation of nodules in soybean plants (glycine max) is controlled by several host genes, which are referred to as rj genes. the soybean cultivar barc2 carries the rj4 gene, which re ... | 2015 | 26187957 |
| genetic diversity of rhizobia isolates from amazon soils using cowpea (vigna unguiculata) as trap plant. | the aim of this work was to characterize rhizobia isolated from the root nodules of cowpea (vigna unguiculata) plants cultivated in amazon soils samples by means of ardra (amplified rdna restriction analysis) and sequencing analysis, to know their phylogenetic relationships. the 16s rrna gene of rhizobia was amplified by pcr (polymerase chain reaction) using universal primers y1 and y3. the amplification products were analyzed by the restriction enzymes hinfi, mspi and ddei and also sequenced wi ... | 2012 | 24031880 |
| rj4, a gene controlling nodulation specificity in soybeans, encodes a thaumatin-like protein but not the one previously reported. | rj4 is a dominant gene in soybeans (glycine max) that restricts nodulation by many strains of bradyrhizobium elkanii. the soybean-b. elkanii symbiosis has a low nitrogen-fixation efficiency, but b. elkanii strains are highly competitive for nodulation; thus, cultivars harboring an rj4 allele are considered favorable. cloning the rj4 gene is the first step in understanding the molecular basis of rj4-mediated nodulation restriction and facilitates the development of molecular tools for genetic imp ... | 2015 | 26582727 |
| draft genome sequence of the nitrogen-fixing symbiotic bacterium bradyrhizobium elkanii 587. | the draft sequence of the genome of bradyrhizobium elkanii 587 is presented. this was obtained using illumina next-gen dna sequencing combined with sanger sequencing. genes for the pathways involved in biological nitrogen fixation (the nif gene cluster), nod genes including nodabc, and genes for the type iii protein secretion system (t3ss) are present. | 2012 | 22689236 |
| hijacking of leguminous nodulation signaling by the rhizobial type iii secretion system. | root-nodule symbiosis between leguminous plants and nitrogen-fixing bacteria (rhizobia) involves molecular communication between the two partners. key components for the establishment of symbiosis are rhizobium-derived lipochitooligosaccharides (nod factors; nfs) and their leguminous receptors (nfrs) that initiate nodule development and bacterial entry. here we demonstrate that the soybean microsymbiont bradyrhizobium elkanii uses the type iii secretion system (t3ss), which is known for its deli ... | 2013 | 24082124 |
| genetic diversity and geographical distribution of indigenous soybean-nodulating bradyrhizobia in the united states. | we investigated the relationship between the genetic diversity of indigenous soybean-nodulating bradyrhizobia and their geographical distribution in the united states using nine soil isolates from eight states. the bradyrhizobia were inoculated on three soybean rj genotypes (non-rj, rj(2)rj(3), and rj(4)). we analyzed their genetic diversity and community structure by means of restriction fragment length polymorphisms of pcr amplicons to target the 16s-23s rrna gene internal transcribed spacer r ... | 2013 | 23563944 |
| genetic divergence of bradyrhizobium strains nodulating soybeans as revealed by multilocus sequence analysis of genes inside and outside the symbiosis island. | the genus bradyrhizobium has been considered to be a taxonomically difficult group. in this study, phylogenetics and evolutionary genetics analyses were used to investigate divergence levels among bradyrhizobium strains nodulating soybeans in china. eleven genospecies were identified by sequence analysis of three phylogenetic and taxonomic markers (smc00019, thra, and trua). this was also supported by analyses of eight genes outside the symbiosis island ("off-island" genes; smc00019, thra, trua, ... | 2014 | 24632260 |
| genome sequence of bradyrhizobium pachyrhizi strain pac48t, a nitrogen-fixing symbiont of pachyrhizus erosus (l.) urb. | bradyrhizobium pachyrhizi pac48(t) has been isolated from a jicama nodule in costa rica. the draft genome indicates high similarity with that of bradyrhizobium elkanii. several coding sequences (cdss) of the stress response might help in survival in the tropics. pac48(t) carries nodd1 and nodk, similar to bradyrhizobium (parasponia) anu 289 and a particular nodd2 gene. | 2015 | 26383651 |
| two major clades of bradyrhizobia dominate symbiotic interactions with pigeonpea in fields of côte d'ivoire. | in smallholder farms of côte d'ivoire, particularly in the northeast of the country, cajanus cajan (pigeonpea) has become an important crop because of its multiple beneficial facets. pigeonpea seeds provide food to make ends meet, are sold on local markets, and aerial parts serve as forage for animals. since it fixes atmospheric nitrogen in symbiosis with soil bacteria collectively known as rhizobia, c. cajan also improves soil fertility and reduces fallow time. yet, seed yields remain low mostl ... | 2016 | 27891120 |
| high-quality permanent draft genome sequence of the bradyrhizobium elkanii type strain usda 76(t), isolated from glycine max (l.) merr. | bradyrhizobium elkanii usda 76(t) (inscd = arag00000000), the type strain for bradyrhizobium elkanii, is an aerobic, motile, gram-negative, non-spore-forming rod that was isolated from an effective nitrogen-fixing root nodule of glycine max (l. merr) grown in the usa. because of its significance as a microsymbiont of this economically important legume, b. elkanii usda 76(t) was selected as part of the doe joint genome institute 2010 genomic encyclopedia for bacteria and archaea-root nodule bacte ... | 2017 | 28270909 |
| draft genome sequence of bradyrhizobium elkanii tnphoa 33, a producer of polyhydroxyalkanoates. | the genus bradyrhizobium comprises bacteria with the ability to form nitrogen-fixing symbioses with legumes. they are of great interest in agriculture, as well as for the production of biopolymers such as polyhydroxyalkanoates. here, we report the draft genome assembly of bradyrhizobium elkanii tnphoa 33 comprising 9 mb, 1,124 contigs, and 9,418 open reading frames. | 2017 | 28232432 |
| whole-genome sequence of bradyrhizobium elkanii strain uasws1016, a potential symbiotic biofertilizer for agriculture. | bradyrhizobium elkanii uasws1016 has been isolated from a wet oxidation sewage plant in italy. fully equipped for ammonia assimilation, heavy metal resistances, and aromatic compounds degradation, it carries a large type iv secretion system, specific of plant-associated microbes. deprived of toxins, it could be considered for agricultural and environmental uses. | 2016 | 27795259 |
| draft genome sequences of bradyrhizobium elkanii strains bly3-8 and bly6-1, which are incompatible with rj3 genotype soybean cultivars. | we report here the draft genome sequences of bradyrhizobium elkanii strains bly3-8 and bly6-1, which are incompatible with rj3 genotype soybean cultivars. the genome sequences of these strains will be useful to identify a causal gene for this incompatibility. | 2016 | 27789639 |
| effector-triggered immunity determines host genotype-specific incompatibility in legume-rhizobium symbiosis. | symbiosis between legumes and rhizobia leads to the formation of n2-fixing root nodules. in soybean, several host genes, referred to as rj genes, control nodulation. soybean cultivars carrying the rj4 gene restrict nodulation by specific rhizobia such as bradyrhizobium elkanii we previously reported that the restriction of nodulation was caused by b. elkanii possessing a functional type iii secretion system (t3ss), which is known for its delivery of virulence factors by pathogenic bacteria. in t ... | 2016 | 27373538 |
| 2,4-dichlorophenoxyacetic acid (2,4-d)- and 2,4,5-trichlorophenoxyacetic acid (2,4,5-t)-degrading gene cluster in the soybean root-nodulating bacterium bradyrhizobium elkanii usda94. | herbicides 2,4-dichlorophenoxyacetic acid (2,4-d)- and 2,4,5-trichlorophenoxyacetic acid (2,4,5-t)-degrading bradyrhizobium strains possess tfdaα and/or cadabc as degrading genes. it has been reported that root-nodulating bacteria belonging to bradyrhizobium elkanii also have tfdaα and cada like genes but lack the ability to degrade these herbicides and that the cada genes in 2,4-d-degrading and non-degrading bradyrhizobium are phylogenetically different. in this study, we identified cadrabck in ... | 2017 | 27296963 |
| draft genome sequence of bradyrhizobium sp. strain br 3262, an effective microsymbiont recommended for cowpea inoculation in brazil. | the strain br 3262 was isolated from nodule of cowpea (vigna unguiculata l. walp) growing in soil of the atlantic forest area in brazil and it is reported as an efficient nitrogen fixing bacterium associated to cowpea. firstly, this strain was assigned as bradyrhizobium elkanii, however, recently a more detailed genetic and molecular characterization has indicated it could be a bradyrhizobium pachyrhizi species. we report here the draft genome sequence of b. pachyrhizi strain br 3262, an elite b ... | 2017 | 27216893 |
| whole-genome sequence of bradyrhizobium elkanii strain uasws1015, a highly ammonia-tolerant nitrifying bacterium. | bradyrhizobium elkanii uasws1015 was isolated from a sewage plant in switzerland. its genome indicates that it is fully equipped for ammonia assimilation and aromatic compound degradation, and it displays a large type iv secretion system, which characterizes plant-associated microbes. totally deprived of toxins, it could be considered for agricultural and environmental uses. | 2016 | 26966217 |
| genome sequence of bradyrhizobium viridifuturi strain semia 690t, a nitrogen-fixing symbiont of centrosema pubescens. | semia 690(t) is a nitrogen-fixing symbiont of centrosema pubescens, and comprises the recently described species bradyrhizobium viridifuturi. its draft genome indicates that it belongs to the bradyrhizobium elkanii superclade. semia 690(t) carries two copies of the regulatory nodd gene, and the nod and nif operons resemble those of bradyrhizobium diazoefficiens. | 2015 | 26679590 |
| an enzyme captured in two conformational states: crystal structure of s-adenosyl-l-homocysteine hydrolase from bradyrhizobium elkanii. | s-adenosyl-l-homocysteine hydrolase (sahase) is involved in the enzymatic regulation of s-adenosyl-l-methionine (sam)-dependent methylation reactions. after methyl-group transfer from sam, s-adenosyl-l-homocysteine (sah) is formed as a byproduct, which in turn is hydrolyzed to adenosine (ado) and homocysteine (hcy) by sahase. the crystal structure of besahase, an sahase from bradyrhizobium elkanii, which is a nitrogen-fixing bacterial symbiont of legume plants, was determined at 1.7 å resolution ... | 2015 | 26627650 |