| genetic diversity and biological control activity of novel species of closely related pseudomonads isolated from wheat field soils in south australia. | rhizobacteria closely related to two recently described species of pseudomonads, pseudomonas brassicacearum and pseudomonas thivervalensis, were isolated from two geographically distinct wheat field soils in south australia. isolation was undertaken by either selective plating or immunotrapping utilizing a polyclonal antibody raised against p. brassicacearum. a subset of 42 isolates were characterized by amplified 16s ribosomal dna restriction analysis (ardra), biolog analysis, and gas chromatog ... | 2000 | 10742249 |
| pseudomonas brassicacearum sp. nov. and pseudomonas thivervalensis sp. nov., two root-associated bacteria isolated from brassica napus and arabidopsis thaliana. | bacteria isolates phenotypically related to pseudomonas corrugata have frequently been isolated from the rhizosphere of arabidopsis thaliana and brassica napus grown on different soils. 16s rdna (rrs) gene sequencing, dna-dna hybridization, biochemical characterization and siderophore typing showed that these isolates belong to two different species that are distinct from other species of the genus pseudomonas, including p. corrugata. a description of properties of these two new species is given ... | 2000 | 10826782 |
| phase-variable expression of an operon encoding extracellular alkaline protease, a serine protease homolog, and lipase in pseudomonas brassicacearum. | the rhizobacterium pseudomonas brassicacearum forms phenotypic variants which do not show extracellular protease and lipase activity. the operon encoding these enzymes, a serine protease homolog, and a type i secretion machinery was characterized. transcriptional lacz gene fusions revealed that the expression of the operon is under the control of phase variation. | 2001 | 11222613 |
| the structure of a local population of phytopathogenic pseudomonas brassicacearum from agricultural soil indicates development under purifying selection pressure. | among the isolates of a bacterial community from a soil sample taken from an agricultural plot in northern germany, a population consisting of 119 strains was obtained that was identified by 16s rdna sequencing and genomic fingerprinting as belonging to the recently described species pseudomonas brassicacearum. analysis of the population structure by allozyme electrophoresis (11 loci) and random amplified polymorphic dna-polymerase chain reaction (rapd-pcr; four primers) showed higher resolution ... | 2001 | 11321534 |
| pseudomonas kilonensis sp. nov., a bacterium isolated from agricultural soil. | a total of 131 bacterial isolates related to pseudomonas corrugata were obtained from an agricultural soil from northern germany. based on 16s rrna gene sequences, pcr-based genome fingerprinting and multilocus enzyme electrophoresis, they formed two groups, a (119 strains) and b (12 strains). as members of each group were highly similar, a single strain of each group was subsequently characterized by a polyphasic taxonomic approach. the selected member of group a was identified as a strain of p ... | 2001 | 11491357 |
| characterization of plant growth promoting rhizobacteria isolated from polluted soils and containing 1-aminocyclopropane-1-carboxylate deaminase. | fifteen bacterial strains containing 1-aminocyclopropane-1-carboxylate (acc) deaminase were isolated from the rhizoplane of pea (pisum sativum l.) and indian mustard (brassica juncea l.) grown in different soils and a long-standing sewage sludge contaminated with heavy metals. the isolated strains were characterized and assigned to various genera and species, such as pseudomonas brassicacearum, pseudomonas marginalis, pseudomonas oryzihabitans, pseudomonas putida, pseudomonas sp., alcaligenes xy ... | 2001 | 11547884 |
| siderophore typing, a powerful tool for the identification of fluorescent and nonfluorescent pseudomonads. | a total of 301 strains of fluorescent pseudomonads previously characterized by conventional phenotypic and/or genomic taxonomic methods were analyzed through siderotyping, i.e., by the isoelectrophoretic characterization of their main siderophores and pyoverdines and determination of the pyoverdine-mediated iron uptake specificity of the strains. as a general rule, strains within a well-circumscribed taxonomic group, namely the species pseudomonas brassicacearum, pseudomonas fuscovaginae, pseudo ... | 2002 | 12039729 |
| phenotypic variation of pseudomonas brassicacearum as a plant root-colonization strategy. | pseudomonas brassicacearum was isolated as a major root-colonizing population from arabidopsis thaliana. the strain nfm421 of p. brassicacearum undergoes phenotypic variation during a. thaliana and brassica napus root colonization in vitro as well as in soil, resulting in different colony appearance on agar surfaces. bacteria forming translucent colonies (phase ii cells) essentially were localized at the surface of young roots and root tips, whereas wild-type cells (phase i cells) were localized ... | 2004 | 15305608 |
| pseudomonas brassicacearum strain am3 containing 1-aminocyclopropane-1-carboxylate deaminase can show both pathogenic and growth-promoting properties in its interaction with tomato. | the role of bacterial 1-aminocyclopropane-1-carboxylate (acc) deaminase activity in the interaction between tomato (lycopersicon esculentum=solanum lycopersicum) and pseudomonas brassicacearum was studied in different strains. the phytopathogenic strain 520-1 possesses acc deaminase activity, an important trait of plant growth-promoting rhizobacteria (pgpr) that stimulates root growth. the acc-utilizing pgpr strain am3 increased in vitro root elongation and root biomass of soil-grown tomato cv. ... | 2007 | 17322547 |
| characterization of the cultivable microbiota of sprouts and their potential for application as protective cultures. | the microbiota of ten seeds and ready-to-eat sprouts produced thereof was characterized by bacteriological culture and denaturing gradient gel electrophoresis (dgge) of amplified dna fragments of the 16s rrna gene. the predominant bacterial biota of hydroponically grown sprouts mainly consisted of enterobacteria, pseudomonades and lactic acid bacteria (lab). for adzuki, alfalfa, mung bean, radish, sesame and wheat, the ratio of these bacterial groups changed strongly in the course of germination ... | 2007 | 17512686 |
| exploration of intraclonal adaptation mechanisms of pseudomonas brassicacearum facing cadmium toxicity. | pseudomonas brassicacearum forms phenotypic variants in vitro as well as in planta during root colonization under natural conditions, leading to subpopulations (phase i and ii cells) that differ in colony morphology and production of exoenzymes/secondary metabolites. the maximal concentration of cadmium allowing both variants growth was 25 mum; however, phase ii cells accumulated fivefold higher cd than phase i cells, even though both variants showed the same growth rate and kinetics, comprising ... | 2007 | 17922765 |
| pseudomonas brassicacearum subsp. neoaurantiaca subsp. nov., orange-pigmented bacteria isolated from soil and the rhizosphere of agricultural plants. | a large group of 38 strains of saprophytic bacteria was isolated from soil and the rhizosphere of agricultural plants. the novel organisms were gram-negative, aerobic, rod-shaped bacteria that produced a green fluorescent pigment, a red-orange diffusible pigment and a complex mixture of phloroglucinol derivates with antimicrobial activity. the latter have not been found in other bacteria, but are peculiar to ferns. the bacteria were vigorous denitrifiers that synthesized levan from sucrose and l ... | 2009 | 19622656 |
| ecology and characterization of polyhydroxyalkanoate-producing microorganisms on and in plants. | polyhydroxyalkanoates are energy reserve polymers produced by bacteria to survive periods of starvation in natural habitats. little is known about the ecology of polyhydroxyalkanoate-producing bacteria. to analyse the occurrence of this specific group on/in seven different plant species, a combined strategy containing culture-dependent and -independent methods was applied. using microbial fingerprint techniques (single-strand conformation polymorphism analysis with specific primers for phac gene ... | 2009 | 19656194 |
| complete genome sequence of a beneficial plant root-associated bacterium, pseudomonas brassicacearum. | to shed light on the genetic equipment of the beneficial plant-associated bacterium pseudomonas brassicacearum, we sequenced the whole genome of the strain nfm421. its genome consists of one chromosome equipped with a repertoire of factors beneficial for plant growth. in addition, a complete type iii secretion system and two complete type vi secretion systems were identified. we report here the first genome sequence of this species. | 2011 | 21515771 |
| multiple transcription-activating sequences regulate the rsmz regulatory small rna of pseudomonas brassicacearum. | the muts-rpos region is known to be a highly polymorphic segment of the chromosome owing to horizontal gene transfer and evolutionary processes. in pseudomonas, muts-fdxa-rsmz-rpos organization is highly conserved, as well as the promoter region of the rsmz small rna (srna)-encoding gene. one exception to this conservation is in pseudomonas brassicacearum, where a 308-nucleotide (nt) sequence, predicted to form a hairpin structure in single-stranded dna (ssdna), is inserted between the rpos and ... | 2012 | 22773788 |
| phenotypic switching in pseudomonas brassicacearum involves gacs- and gaca-dependent rsm small rnas. | the plant-beneficial bacterium pseudomonas brassicacearum forms phenotypic variants in vitro as well as in planta during root colonization under natural conditions. transcriptome analysis of typical phenotypic variants using microarrays containing coding as well as noncoding dna fragments showed differential expression of several genes relevant to secondary metabolism and of the small rna (srna) genes rsmx, rsmy, and rsmz. naturally occurring mutations in the gacs-gaca system accounted for pheno ... | 2012 | 22247157 |
| draft genome sequences of the three pectobacterium-antagonistic bacteria pseudomonas brassicacearum pp1-210f and pa1g7 and bacillus simplex ba2h3. | pectobacterium spp. are bacterial pathogens causing soft rot diseases on a wide range of plants and crops. we present in this paper the draft genome sequences of three bacterial strains, pseudomonas brassicacearum pp1-210f and pa1g7 and bacillus simplex ba2h3, which exhibit antagonistic activities against the pectobacterium plant pathogens. | 2015 | 25635020 |
| medicago truncatula gaertn. as a model for understanding the mechanism of growth promotion by bacteria from rhizosphere and nodules of alfalfa. | the present study showed all the 16 strains isolated and identified from the alfalfa rhizosphere and nodules, and registered in genbank, to be good candidates for targeted use in studies addressing the rather weak known mechanism of plant growth promotion, including that of medicago truncatula, a molecular crop model. based on physiological, biochemical and molecular analysis, the 16 isolates obtained were ascribed to the following five families: bacillaceae, rhizobiaceae, xantomonadaceae, enter ... | 2016 | 26861677 |
| bacteria-zinc co-localization implicates enhanced synthesis of cysteine-rich peptides in zinc detoxification when brassica juncea is inoculated with rhizobium leguminosarum. | some plant growth promoting bacteria (pgpb) are enigmatic in enhancing plant growth in the face of increased metal accumulation in plants. since most pgpb colonize the plant root epidermis, we hypothesized that pgpb confer tolerance to metals through changes in speciation at the root epidermis. we employed a novel combination of fluorophore-based confocal laser scanning microscopic imaging and synchrotron based microscopic x-ray fluorescence mapping with x-ray absorption spectroscopy to characte ... | 2015 | 26263508 |
| leveraging the attributes of mucor hiemalis-derived silver nanoparticles for a synergistic broad-spectrum antimicrobial platform. | driven by the need to engineer robust surface coatings for medical devices to prevent infection and sepsis, incorporation of nanoparticles has surfaced as a promising avenue to enhance non-fouling efficacy. microbial synthesis of such nanoscale metallic structures is of substantive interest as this can offer an eco-friendly, cost-effective, and sustainable route for further development. here we present a mucor hiemalis-derived fungal route for synthesis of silver nanoparticles, which display sig ... | 2016 | 28018316 |
| complete genome sequence of pseudomonas brassicacearum lbum300, a disease-suppressive bacterium with antagonistic activity toward fungal, oomycete, and bacterial plant pathogens. | pseudomonas brassicacearum lbum300, a plant rhizosphere-inhabiting bacterium, produces 2,4-diacetylphloroglucinol and hydrogen cyanide and has shown antagonistic activity against the plant pathogens verticillium dahliae, phytophthora cactorum, and clavibacter michiganensis subsp. michiganensis. here, we report the complete genome sequence of p. brassicacearum lbum300. | 2016 | 26823582 |
| paradox of plant growth promotion potential of rhizobacteria and their actual promotion effect on growth of barley (hordeum vulgare l.) under salt stress. | from the rhizosphere of two salt tolerant plant species, hordeum secalinum and plantago winteri growing in a naturally salt meadow, 100 strains were isolation on enrichment media for various plant growth-promoting (pgp) functions (acc deaminase activity, auxin synthesis, calcium phosphate mobilization and nitrogen fixation). based on the taxonomic affiliation of the isolated bacteria and their enrichment medium 22 isolates were selected to test their growth promotion effect on the crop barley (h ... | 2015 | 26640049 |
| isolation and characterization of pseudomonas brassicacearum j12 as an antagonist against ralstonia solanacearum and identification of its antimicrobial components. | a bacterial strain, j12, isolated from the rhizosphere soil of tomato plants strongly inhibited the growth of phytopathogenic bacteria ralstonia solanacearum. strain j12 was identified as pseudomonas brassicacearum based on its 16s rrna gene sequence. j12 could produce 2,4-diacetylphloroglucinol (2,4-dapg), hydrogen cyanide (hcn), siderophore(s) and protease. the maximum growth and antagonistic activity were recorded at 30°c and ph 8. glucose and tryptone were used as the most suitable carbon an ... | 2012 | 22361469 |
| complete genome sequence of pseudomonas brassicacearum strain l13-6-12, a biological control agent from the rhizosphere of potato. | pseudomonas brassicacearum strain l13-6-12 is a rhizosphere colonizer of potato, lettuce and sugar beet. previous studies have shown that this motile, gram-negative, non-sporulating bacterium is an effective biocontrol agent against different phytopathogens. here, we announce and describe the complete genome sequence of p. brassicacearum l13-6-12 consisting of a single 6.7 mb circular chromosome that consists of 5773 protein coding genes and 85 rna-only encoding genes. genome analysis revealed g ... | 2017 | 28078051 |
| simultaneous aerobic denitrification and cr(vi) reduction by pseudomonas brassicacearum lz-4 in wastewater. | inorganic nitrogen and heavy metals pervasively co-exist in industrial and domestic wastewaters. in this work, pseudomonas brassicacearum lz-4 was tested for the simultaneous reduction of cr(vi) and nitrate. nitrate was found to be the best inorganic nitrogen source for strain lz-4, and could promote cr(vi) reduction. cr(vi) had a low degree of inhibition on denitrification, and even 50mgl(-1) cr(vi) did not inhibit reduction of 100mgl(-1) no3(-)-n. the capability of simultaneous reduction of cr ... | 2016 | 27639231 |
| pseudomonas brassicacearum strain df41 kills caenorhabditis elegans through biofilm-dependent and biofilm-independent mechanisms. | pseudomonas brassicacearum df41 is a biocontrol agent that suppresses disease caused by the fungal pathogen sclerotinia sclerotiorum a number of exometabolites are produced by df41 including the lipopeptide sclerosin, hydrogen cyanide (hcn) and degradative enzymes. production of these compounds is controlled at both the transcriptional and posttranscriptional level by quorum sensing (qs) and the gac-two component regulatory system. in order to be successful, a biocontrol agent must persist in th ... | 2016 | 27637885 |
| remote biodegradation of ge-imogolite nanotubes controlled by the iron homeostasis of pseudomonas brassicacearum. | the toxicity of high-aspect-ratio nanomaterials (harns) is often associated with oxidative stress. the essential nutrient fe may also be responsible of oxidative stress through the production of reactive oxygen species. in the present study, it has been examined to what extent adding fenton reaction promoting fe impacted the toxicity of an alumino-germanate model harn. structural addition of only 0.95% wt fe to ge-imogolite not only alleviated the toxicity observed in the case of fe-free nanotub ... | 2016 | 27347687 |
| pyoverdine and histicorrugatin-mediated iron acquisition in pseudomonas thivervalensis. | the genome of pseudomonas thivervalensis lmg 21626(t) has been sequenced and a genomic, genetic and structural analysis of the siderophore mediated iron acquisition was undertaken. pseudomonas thivervalensis produces two structurally new siderophores, pyoverdine pyothi which is typical for p. thivervalensis strains and a closely related strain, and the lipopeptidic siderophore histicorrugatin which is also detected in p. lini. histicorrugatin consists out of an eight amino acid long peptide whic ... | 2016 | 27007713 |
| rhizosphere competence of wild-type and genetically engineered pseudomonas brassicacearum is affected by the crop species. | 2,4-diacetylphloroglucinol (2,4-dapg)-producing pseudomonas brassicacearum q8r1-96 is a highly effective biocontrol agent of take-all disease of wheat. strain z30-97, a recombinant derivative of q8r1-96 containing the phzabcdefg operon from p. synxantha (formerly p. fluorescens) 2-79 inserted into its chromosome, also produces phenazine-1-carboxylic acid. rhizosphere population sizes of q8r1-96, z30-97, and 2-79, introduced into the soil, were assayed during successive growth cycles of barley, n ... | 2016 | 26926486 |
| mechanism of biological denitrification inhibition: procyanidins induce an allosteric transition of the membrane-bound nitrate reductase through membrane alteration. | recently, it has been shown that procyanidins from fallopia spp. inhibit bacterial denitrification, a phenomenon called biological denitrification inhibition (bdi). however, the mechanisms involved in such a process remain unknown. here, we investigate the mechanisms of bdi involving procyanidins, using the model strain pseudomonas brassicacearum nfm 421. the aerobic and anaerobic (denitrification) respiration, cell permeability and cell viability of p. brassicacearum were determined as a functi ... | 2016 | 26906096 |
| mixed planting with a leguminous plant outperforms bacteria in promoting growth of a metal remediating plant through histidine synthesis. | the effectiveness of plant growth promoting bacteria (pgpb) in improving metal phytoremediation is still limited by stunted plant growth under high soil metal concentrations. meanwhile, mixed planting with leguminous plants is known to improve yield in nutrient deficient soils but the use of a metal tolerant legume to enhance metal tolerance of a phytoremediator has not been explored. we compared the use of pseudomonas brassicacearum, rhizobium leguminosarum, and the metal tolerant leguminous pl ... | 2016 | 26682469 |
| various effects of fluorescent bacteria of the genus pseudomonas containing acc deaminase on wheat seedling growth. | the study evaluates the effect of rhizobacteria having 1-aminocyclopropane-1-carboxylate deaminase (accd) on the development of wheat seedlings. this enzyme has been proposed to play a key role in microbe-plant association. three fluorescent pseudomonads containing this deaminase were selected from 70 strains of pseudomonads isolated from rhizosphere of wheat (triticum aestivum l.) and rape (brassica napus l.). these bacteria, varied significantly in the ability to both biosynthesize auxins and ... | 2015 | 25983132 |
| mechanisms behind bacteria induced plant growth promotion and zn accumulation in brassica juncea. | the growth and metal-extraction efficiency of plants exposed to toxic metals has been reported to be enhanced by inoculating plants with certain bacteria but the mechanisms behind this process remain unclear. we report results from glasshouse experiments on brassica juncea plants exposed to 400mgznkg(-1) that investigated the abilities of pseudomonas brassicacearum and rhizobium leguminosarum to promote growth, coupled with synchrotron based μxanes analysis to probe zn speciation in the plant ro ... | 2015 | 25464287 |
| genome sequence of pseudomonas brassicacearum df41. | pseudomonas brassicacearum df41, a gram-negative soil bacterium, is able to suppress the fungal pathogen sclerotinia sclerotiorum through a process known as biological control. here, we present a 6.8-mb assembly of its genome, which is the second fully assembled genome of a p. brassicacearum strain. | 2014 | 24812222 |
| bioactive alkaloids produced by pseudomonas brassicacearum subsp. neoaurantiaca, an endophytic bacterium from salvia miltiorrhiza. | eleven compounds were isolated from the culture of an endophytic bacterium pseudomonas brassicacearum subsp. neoaurantiaca in salvia miltiorrhiza bunge. their structures were elucidated by spectroscopic methods as cyclo-(gly-l-ala) (1), cyclo-(l-ala-l-ala) (2), cyclo-(l-pro-gly) (3), cyclo-(l-pro-l-ser) (4), cyclo-(l-ala-trans-4-hydroxy-l-pro) (5), cyclo-(l-val-l-pro) (6), cyclo-(gly-l-tyr) (7), cyclo-(l-ala-l-tyr) (8), cyclo-(l-tyr-trans-4-hydroxy-l-pro) (9), 3-methylhydantoin (10) and 2-piperi ... | 2013 | 22765159 |
| interaction between 2,4-diacetylphloroglucinol- and hydrogen cyanide-producing pseudomonas brassicacearum lbum300 and clavibacter michiganensis subsp. michiganensis in the tomato rhizosphere. | we have previously demonstrated that inoculation of tomato plants with 2,4-diacetylphloroglucinol (dapg)- and hydrogen cyanide (hcn)-producing pseudomonas brassicacearum lbum300 could significantly reduce bacterial canker symptoms caused by clavibacter michiganensis subsp. michiganensis in this study, in order to better characterize the population dynamics of lbum300 in the rhizosphere of tomato plants, we characterized the role played by dapg and hcn production by lbum300 on rhizosphere coloniz ... | 2017 | 28432096 |
| the naphthalene catabolic protein nahg plays a key role in hexavalent chromium reduction in pseudomonas brassicacearum lz-4. | soil contamination by pah and heavy metals is a growing problem. here, we showed that a new isolate, pseudomonas brassicacearum strain lz-4, can simultaneously degrade 98% of 6 mm naphthalene and reduce 92.4% of 500 μm hexavalent chromium [cr (vi)] within 68 h. a draft genome sequence of strain lz-4 (6,219,082 bp) revealed all the genes in the naphthalene catabolic pathway and some known cr (vi) reductases. interestingly, genes encoding naphthalene pathway components were upregulated in the pres ... | 2017 | 28852154 |