Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
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| genetic rearrangement of the atzab atrazine-degrading gene cassette from padp1::tn5 to the chromosome of variovorax sp. md1 and md2. | we report the characterization of the rearrangement phenomena responsible for the movement of the atrazine-degrading atza and b genes from padp1::tn5 to the chromosome of variovorax sp. md1 and md2. long pcrs and southern blot analyses revealed that the two genes forming a gene cassette moved in a unique rearrangement event. it also revealed that the boundaries of the plasmid sequence inserted in the chromosome correspond to is1071or to sequences close to is1071. it suggests that this genetic re ... | 2007 | 17188820 |
| hydrogen cyanide-producing rhizobacteria kill subterranean termite odontotermes obesus (rambur) by cyanide poisoning under in vitro conditions. | the subterranean termite odontotermes obesus is an important pest of the indian subcontinent, causing extensive damage to major agricultural crops and forest plantation trees. control of termites by strategies employing their parasites has limitations because they have evolved a complex social structure, immune responses, and adaptive behavior toward pathogen-infected individuals. nonparasitic rhizobacteria that produce harmful metabolites might facilitate the biocontrol of termites. in the pres ... | 2007 | 17171461 |
| agrobacterium-mediated transformation of protocorm-like bodies in cymbidium. | genetically transformed plants of cymbidium were regenerated after cocultivating protocorm-like bodies (plb) with agrobacterium tumefaciens strain eha101 (pig121hm) that harbored genes for beta-glucuronidase (gus), hygromycin phosphotransferase (hpt) and neomycin phosphotransferase ii (nptii). plb of three genotypes maintained in liquid new dogashima medium (ndm), were subjected to transformation experiments. the plb inoculated with agrobacterium produced secondary plb, 4 weeks after transfer on ... | 2007 | 17205333 |
| the use of the phosphomannose isomerase gene as alternative selectable marker for agrobacterium-mediated transformation of flax (linum usitatissimum). | in order to meet the future requirement of using non-antibiotic resistance genes for the production of transgenic plants, we have adapted the selectable marker system pmi/mannose to be used in agrobacterium-mediated transformation of flax (linum usitatissimum l.) cv. barbara. the escherichia coli pmi gene encodes a phosphomannose isomerase (e.c. 5.1.3.8) that converts mannose-6-phosphate, an inhibitor of glycolysis, into fructose-6-phosphate (glycolysis intermediate). its expression in transform ... | 2007 | 17205337 |
| crystal structure of agr_c_4470p from agrobacterium tumefaciens. | we report here the crystal structure at 2.0 a resolution of the agr_c_4470p protein from the gram-negative bacterium agrobacterium tumefaciens. the protein is a tightly associated dimer, each subunit of which bears strong structural homology with the two domains of the heme utilization protein chus from escherichia coli and hems from yersinia enterocolitica. remarkably, the organization of the agr_c_4470p dimer is the same as that of the two domains in chus and hems, providing structural evidenc ... | 2007 | 17322535 |
| characterization of vascular-specific rss1 and rolc promoters for their utilization in engineering plants to develop resistance against hemipteran insect pests. | rice sucrose synthase1, rss1 (isolated from rice) and rolc (isolated from agrobacterium rhizogenes) promoters were evaluated by binding analyses of their respective cis-elements with host nuclear transcription factors. the expression profile of an insecticidal protein driven by these promoters in transgenic plants was monitored. motif-search analysis with available phloem-specific promoter sequences revealed the presence of two boxii elements in rss1. an octopine synthase element, a stem-specifi ... | 2007 | 17323077 |
| chemolithoautotrophic oxidation of thiosulfate, tetrathionate and thiocyanate by a novel rhizobacterium belonging to the genus paracoccus. | two tropical leguminous-rhizospheric strains, sst and jt 001, phylogenetically closest to paracoccus thiocyanatus and paracoccus pantotrophus, respectively, were isolated on reduced sulfur compounds as sole energy and electron sources. while sst had versatile chemolithotrophic abilities to oxidize thiosulfate, tetrathionate, thiocyanate, sulfide and elemental sulfur, jt 001 could oxidize thiosulfate, soluble sulfide, elemental sulfur and a relatively lesser amount of tetrathionate. positive hybr ... | 2007 | 17326754 |
| salidroside production by hairy roots of rhodiola sachalinensis obtained after transformation with agrobacterium rhizogenes. | hairy roots induced by agrobacterium rhizogenes grow faster, and are considered as genetically stable. these hairy roots can be used as an interesting material for the production of secondary metabolites of pharmaceutical value. salidroside has been identified as the major compounds from the roots of rhodiola sachalinensis a. bor. here, we provide an update that adds new perspectives on the prospects and challenges of producing salidroside from hairy roots induced by agrobacterium rhizogene in r ... | 2007 | 17329834 |
| microbial enzymes involved in lactone compound metabolism and their biotechnological applications. | lactone compounds are widely distributed in nature and play important roles in organisms. these compounds are synthesized and metabolized enzymatically in vivo; however, detailed investigation of these enzymes lags behind that of other common enzymes. in this paper, recent work on the enzymes involved in the metabolism of lactone compounds will be reviewed. in particular, fundamental and application studies on lactonases and baeyer-villiger monooxgenases of microbial origin are described. | 2007 | 17333168 |
| [t-dna-induced mutations in transgenic plants]. | the review surveys experimental data on changes of individual traits in genetically modified (transgenic) plants. the attention is focused on mutations induced by t-dna insertions upon agrobacterium-induced transformation of dicotyledonous plants. the character of mutation appearance in transgenic plants is examined. the prospects of mutations induced by t-dna insertions are considered. | 2007 | 17333933 |
| verification and rapid identification of soybean rhizobia in indian soils. | sixty root nodule isolates of soybean rhizobia indigenous to eight field sites in india were characterized using pcr-rflp for repeated sequence rsalpha a 1195-bp dna fragment, indole acetic acid production, and nitrogenase activity. site-dependent variations were observed in terms of iaa production and nitrogenase activities. rsalpha was conserved in slow-growing soybean rhizobia across locations and sites and was absent in other rhizobiaceae members and other bacterial genera. the results sugge ... | 2007 | 17334844 |
| making a friend from a foe: expressing a groel gene from the whitefly bemisia tabaci in the phloem of tomato plants confers resistance to tomato yellow leaf curl virus. | some (perhaps all) plant viruses transmitted in a circulative manner by their insect vectors avoid destruction in the haemolymph by interacting with groel homologues, ensuring transmission. we have previously shown that the phloem-limited begomovirus tomato yellow leaf curl virus (tylcv) interacts in vivo and in vitro with groel produced by the whitefly vector bemisia tabaci. in this study, we have exploited this phenomenon to generate transgenic tomato plants expressing the whitefly groel in th ... | 2007 | 17334947 |
| inhibition of lipid a biosynthesis as the primary mechanism of chir-090 antibiotic activity in escherichia coli. | the deacetylation of udp-3-o-[(r)-3-hydroxymyristoyl]-n-acetylglucosamine (udp-3-o-acyl-glcnac) by lpxc is the committed reaction of lipid a biosynthesis. chir-090, a novel n-aroyl-l-threonine hydroxamic acid, is a potent, slow, tight-binding inhibitor of the lpxc deacetylase from the hyperthermophile aquifex aeolicus, and it has excellent antibiotic activity against pseudomonas aeruginosa and escherichia coli, as judged by disk diffusion assays. we now report that chir-090 is also a two-step sl ... | 2007 | 17335290 |
| evolving ideas of legume evolution and diversity: a taxonomic perspective on the occurrence of nodulation. | legumes evolved about 60 million years ago (ma), and nodulation 58 ma. nonnodulation remains common in caesalpinioideae, with smaller numbers in mimosoideae and papilionoideae. the first type of infection by bacteria may have been at junctions where lateral roots emerged, followed by formation of infection threads to confine bacteria and convey them to some cells in the developing nodule, where they were generally released into symbiosomes. infection threads were a prerequisite for root-hair inf ... | 2007 | 17335493 |
| metal induction of a paxillus involutus metallothionein and its heterologous expression in hebeloma cylindrosporum. | * metallothioneins are small polypeptides involved in metal tolerance of many eukaryotes. here we characterized the pimt1 gene, coding for a metallothionein from the ectomycorrhizal fungus paxillus involutus. * expression of pimt1 in p. involutus under metal stress conditions was measured by northern blot and rt-pcr analyses. the full-length cdna was used to perform functional complementation in yeast mutant strains and agrotransformation of hebeloma cylindrosporum. * heterologous expression in ... | 2007 | 17335505 |
| silencing of beta-carotene hydroxylase increases total carotenoid and beta-carotene levels in potato tubers. | beta-carotene is the main dietary precursor of vitamin a. potato tubers contain low levels of carotenoids, composed mainly of the xanthophylls lutein (in the beta-epsilon branch) and violaxanthin (in the beta-beta branch). none of these carotenoids have provitamin a activity. we have previously shown that tuber-specific silencing of the first step in the epsilon-beta branch, lcy-e, redirects metabolic flux towards beta-beta carotenoids, increases total carotenoids up to 2.5-fold and beta-caroten ... | 2007 | 17335571 |
| characterization and transient replication of tomato leaf curl virus defective dnas. | distinct subgenomic dna species known as defective (df) dna molecules were found in plants infected with tomato leaf curl virus (tlcv). four df dnas derived from tlcv type and darwin 1 strains were found to contain large deletions that disrupt all of the viral genes required for viral replication, encapsidation and spread. however, the viral origin of replication (ori), including the replication-associated protein (rep) binding domains, was present in all four df dnas. co-agroinfection of leaf s ... | 2007 | 17347773 |
| genome-wide functional analysis of pathogenicity genes in the rice blast fungus. | rapid translation of genome sequences into meaningful biological information hinges on the integration of multiple experimental and informatics methods into a cohesive platform. despite the explosion in the number of genome sequences available, such a platform does not exist for filamentous fungi. here we present the development and application of a functional genomics and informatics platform for a model plant pathogenic fungus, magnaporthe oryzae. in total, we produced 21,070 mutants through l ... | 2007 | 17353894 |
| quorum-sensing regulation in rhizobia and its role in symbiotic interactions with legumes. | legume-nodulating bacteria (rhizobia) usually produce n-acyl homoserine lactones, which regulate the induction of gene expression in a quorum-sensing (or population-density)-dependent manner. there is significant diversity in the types of quorum-sensing regulatory systems that are present in different rhizobia and no two independent isolates worked on in detail have the same complement of quorum-sensing genes. the genes regulated by quorum sensing appear to be rather diverse and many are associa ... | 2007 | 17360278 |
| cell-cell communication in the plant pathogen agrobacterium tumefaciens. | the plant pathogen agrobacterium tumefaciens induces the formation of crown gall tumours at wound sites on host plants by directly transforming plant cells. this disease strategy benefits the bacteria as the infected plant tissue produces novel nutrients, called opines, that the colonizing bacteria can use as nutrients. almost all of the genes that are required for virulence, and all of the opine uptake and utilization genes, are carried on large tumour-inducing (ti) plasmids. the observation mo ... | 2007 | 17360279 |
| [obtaining marker-free transgenic soybean plants with optimal frequency by constructing three t-dnas binary vector]. | obtaining marker-free plants with high efficiency will benefit the environmental release of transgenic crops. to achieve this point, a binary vector pnb35svip1 with three t-dnas was constructed by using several mediate plasmids, in which one copy of bar gene expression cassette and two copies of vip1 gene expression cassette were included. eha101 agrobacterium strain harboring the final construct was applied to transform soybean (glycine max) cotyledon nodes. through 2 - 3 months regeneration an ... | 2007 | 17366903 |
| traa, trac and trad autorepress two divergent quorum-regulated promoters near the transfer origin of the ti plasmid of agrobacterium tumefaciens. | whole-genome transcriptional profiling experiments were performed to identify the complete set of trar-regulated genes in isogenic a. tumefaciens strains containing an octopine-type or nopaline-type ti plasmid. most of the known trar-regulated genes as well as a number of new inducible genes were identified. surprisingly, some known members of this regulon showed both weaker induction and weak levels of expression than we had predicted based upon earlier studies. in particular, traa was expresse ... | 2007 | 17367394 |
| caspase-resistant vird2 protein provides enhanced gene delivery and expression in plants. | agrobacterium tumefaciens vird2 protein is one of the key elements of agrobacterium-mediated plant transformation, a process of transfer of t-dna sequence from the agrobacterium tumour inducing plasmid into the nucleus of infected plant cells and its integration into the host genome. the vird2 protein has been shown to be a substrate for a plant caspase-like protease activity (pclp) in tobacco. we demonstrate here that mutagenesis of the vird2 protein to prevent cleavage by pclp increases the ef ... | 2007 | 17370074 |
| hrt and nutrients affect bacterial communities grown on recirculation aquaculture system effluents. | in a recirculation aquaculture system the drumfilter effluent can be used as substrate for heterotrophic bacterial production, which can be recycled as feed. because the bacteria might contain pathogens, which could reduce its suitability as feed, it is important to characterize these communities. bacteria were produced in growth reactors under different conditions: 7 h hydraulic retention time (hrt) vs. 2 h, sodium acetate vs. molasses, and ammonia vs. nitrate. the community of the drumfilter e ... | 2007 | 17371322 |
| characterization of t-dna insertion patterns in the genome of rice blast fungus magnaporthe oryzae. | agrobacterium tumefaciens-mediated transformation (atmt) has been proven to be a powerful strategy for gene disruption in plants and fungi. patterns associated with transferred dna (t-dna) integration in plants and yeast have been studied comprehensively, whereas no detailed analysis of t-dna integration has been reported yet in filamentous fungi. here, we reported the t-dna insertion patterns in the genome of filamentous fungus magnaporthe oryzae. using atmt, a t-dna tagged population consistin ... | 2007 | 17372735 |
| [the pssa gene encodes udp-glucose: polyprenyl phosphate-glucosyl phosphotransferase initiating biosynthesis of rhizobium leguminosarum exopolysaccharide]. | symbiotic nitrogen-fixing bacteria rhizobium leguminosarum by. viciae vf39 secrete an acidic heteropolysaccharide, the biosynthesis of which involves the stage of polyprenyl diphosphate octasaccharide formation, with its carbohydrate fragment corresponding to the repeating polymer unit. the amino acid analysis of the product of the pssa gene, we have earlier identified, showed its homology to bacterial polyisoprenyl phosphate hexose 1-phosphate transferases catalyzing the formation of phosphodie ... | 2007 | 17375671 |
| the quorum-sensing transcription factor trar decodes its dna binding site by direct contacts with dna bases and by detection of dna flexibility. | trar of agrobacterium tumefaciens is a member of the luxr family of transcriptional regulators, and binds to specific dna sequences (tra boxes) at target promoters of the tumour-inducing (ti) plasmid. each tra box has a pronounced dyad symmetry, and each subunit of a trar dimer binds to one half of a tra box via a helix-turn-helix (hth) dna binding motif. structural analysis has suggested that trar makes extensive sequence-specific contacts with tra box dna. in this study, we tested these predic ... | 2007 | 17376086 |
| symbiosis-induced cascade regulation of the mesorhizobium loti r7a virb/d4 type iv secretion system. | the mesorhizobium loti r7a symbiosis island contains genes encoding a virb/d4 type iv secretion system (t4ss) similar to that of agrobacterium tumefaciens. this system has host-dependent effects on symbiosis that probably are due to translocation of two effector proteins, msi059 and msi061, into host cells. here we report that, as in a. tumefaciens, the m. loti vir genes are transcriptionally regulated by a vira/virg two-component regulatory system. a virgn54d mutant gene of m. loti caused const ... | 2007 | 17378428 |
| rhizobium-initiated rice growth inhibition caused by nitric oxide accumulation. | isolates of rhizobium leguminosarum bv. trifolii (the clover root-nodule endosymbiont) from the nile river delta have been found to infect rice roots and colonize the intercellular spaces of the rice roots. some of these isolates inhibit rice seedling growth but one in particular, r4, has been found in rice roots which develop and grow normally. we present evidence that the induced growth inhibition is due to a toxic accumulation of nitric oxide (no), from the reduction of nitrate, and suggest t ... | 2007 | 17378431 |
| rhizobium tropici response to acidity involves activation of glutathione synthesis. | rhizobium tropici ciat899 displays intrinsic tolerance to acidity, and efficiently nodulates phaseolus vulgaris at low ph. by characterizing a gshb mutant strain, glutathione has been previously demonstrated to be essential for r. tropici tolerance to acid stress. the wild-type gshb gene region has been cloned and its transcription profile has been characterized by using quantitative real-time pcr and transcriptional gene fusions. activation of the gshb gene under acid-stress conditions was demo ... | 2007 | 17379738 |
| suppressor of rna silencing encoded by the monopartite tomato leaf curl java begomovirus. | we previously isolated the monopartite begomovirus tomato leaf curl java virus (tolcjav) and satellite dnabeta02 from the same naturally infected tomato source in indonesia. tolcjav induced mild leaf curl symptoms in nicotiana benthamiana plants; dnabeta02 encoded the betac1 gene and produced severe leaf curl symptoms when co-inoculated with tolcjav in n. benthamiana. however, dnabeta02mbetac1, which contains a frame shift mutation, did not induce severe symptoms in n. benthamiana when co-inocul ... | 2007 | 17385070 |
| response of inoculated foliar fed pea plants (pisum sativum l.) to reduced mo supply. | the application of nutrients to the roots and leaves of inoculated pea plants grown under conditions of reduced mo supply was studied. pea plants (pisum sativum l.) were grown on liquid nutrient solution excluding mo from the media until the 35th day under glasshouse conditions. plants were inoculated with the bacterial suspension of rhizobium leguminosarum bv. vicae, strain d293 at approximately 10(8) cells per cm3. the foliar fertilizer agroleaf was applied at 0.3% concentration. changes in th ... | 2007 | 17385546 |
| abnormal accumulation of sugars and phenolics in tobacco roots expressing the agrobacterium t-6b oncogene and the role of these compounds in 6b-induced growth. | the agrobacterium t-dna oncogene 6b induces tumors and modifies the growth of transgenic plants by an unknown mechanism. we have investigated changes in roots of tobacco seedlings that express a dexamethasone-inducible t-6b (dex-t-6b) gene. on induction medium with sucrose, intact or isolated dex-t-6b roots accumulated sucrose, glucose, and fructose and changed their growth, contrary to noninduced roots. root fragments bridging agar blocks with or without sucrose accumulated sugars at the site o ... | 2007 | 17249422 |
| cancer determining information transmission and circulation. | cancer determining information transmission, typically oncogene transfer, is known in many cases of virus initiated tumors. transmission of carcinogenic information, that stored in plasmids named t-dnas, is also known to take place in one type of bacteria induced tumor, that caused by agrobacterium tumefaciens in dicotyledon plants roots. other mechanisms of carcinogenic information transmission have been more recently recognized, that involve horizontal transfer of genetic material among cells. ... | 2007 | 17252205 |
| structural and regulatory genes required to make the gas dimethyl sulfide in bacteria. | dimethyl sulfide (dms) is a key compound in global sulfur and carbon cycles. dms oxidation products cause cloud nucleation and may affect weather and climate. dms is generated largely by bacterial catabolism of dimethylsulfoniopropionate (dmsp), a secondary metabolite made by marine algae. we demonstrate that the bacterial gene dddd is required for this process and that its transcription is induced by the dmsp substrate. cloned dddd from the marine bacterium marinomonas and from two bacterial st ... | 2007 | 17272727 |
| agrobacterium rubi(t) dsm 6772 produces a lipophilic polysaccharide capsule whose degree of acetylation is growth modulated. | the structure of the capsular polysaccharide produced from the type strain of agrobacterium rubi dsm 6772 is demonstrated by means of chemical and spectroscopical methodologies. it is constituted from the quite rare monosaccharide 6-deoxy-l-talose, involved in alternating alpha-(1 --> 2) and alpha-(1 --> 3) linkages. this simple backbone is further complicated from the occurrence of o-acetyl substituents located always at o-2 of the o-3 substituted 6-deoxy-talose. this decoration is not stoichio ... | 2007 | 17284069 |
| [calcium and nod signaling]. | 2007 | 17291420 | |
| the mtmmpl1 early nodulin is a novel member of the matrix metalloendoproteinase family with a role in medicago truncatula infection by sinorhizobium meliloti. | we show here that mtmmpl1, a medicago truncatula nodulin gene previously identified by transcriptomics, represents a novel and specific marker for root and nodule infection by sinorhizobium meliloti. this was established by determining the spatial pattern of mtmmpl1 expression and evaluating gene activation in the context of various plant and bacterial symbiotic mutant interactions. the mtmmpl1 protein is the first nodulin shown to belong to the large matrix metalloendoproteinase (mmp) family. w ... | 2007 | 17293436 |
| improved expression of recombinant gfp using a replicating vector based on beet curly top virus in leaf-disks and infiltrated nicotiana benthamiana leaves. | recombinant green fluorescent protein (gfp) with a molecular mass of 29 kda was transiently expressed in agrobacterium-inoculated leaf-disks prepared from nicotiana benthamiana plants. expression of gfp from the cauliflower mosaic virus (camv) 35 s promoter within a replicating vector based on the geminivirus beet curly top virus (bctv) was more than 3 times higher than from a control, non-replicating vector. use of the cassava vein mosaic virus (csvmv) promoter in the bctv replicating vector in ... | 2007 | 17294255 |
| reconstitution of the biochemical activities of the attj repressor and the attk, attl, and attm catabolic enzymes of agrobacterium tumefaciens. | the attklm operon encodes a lactonase (attm) that hydrolyzes acylhomoserine lactone autoinducers, as well as two putative dehydrogenases (attk and attl). here we show that attk, attl, and attm collectively covert gamma-butyrolactone to succinate. two metabolic intermediates, gamma-hydroxybutyrate and succinic semialdehyde, inactivated the attj repressor in vitro and induced attklm transcription in vivo. | 2007 | 17307843 |
| new insights into microbial oxidation of antimony and arsenic. | sb(iii) oxidation was documented in an agrobacterium tumefaciens isolate that can also oxidize as(iii). equivalent sb(iii) oxidation rates were observed in the parental wild-type organism and in two well-characterized mutants that cannot oxidize as(iii) for fundamentally different reasons. therefore, despite the literature suggesting that sb(iii) and as(iii) may be biochemical analogs, sb(iii) oxidation is catalyzed by a pathway different than that used for as(iii). sb(iii) and as(iii) oxidation ... | 2007 | 17308197 |
| purification and characterization of mannose/glucose-specific lectin from seeds of trigonella foenumgraecum. | a lectin present in seeds of trigonella foenumgraecum was isolated and purified by acid precipitation, salt fractionation, and affinity chromatography on mannan cross-linked agarose. sds-page revealed a single band corresponding to a molecular weight of 27,350 daltons. the lectin agglutinated trypsin-treated rat erythrocytes. sugar specificity as determined by hemagglutination inhibition assay indicated that the lectin belongs to a glucose/mannose-specific group. the reaction of the lectin with ... | 2007 | 17309436 |
| development of a simple and rapid agrobacterium tumefaciens-mediated transformation system for the entomopathogenic fungus metarhizium anisopliae var. acridum. | to examine the ability of agrobacterium to attach to metarhizium anisopliae var. acridum strain cg423 under co-cultivation and to develop an agrobacterium-mediated method of gene delivery into strain cg423, a promising agent for biological control of grasshoppers. | 2007 | 17309500 |
| 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 |
| coupling two mercury resistance genes in eastern cottonwood enhances the processing of organomercury. | eastern cottonwood (populus deltoides bartr. ex marsh.) trees were engineered to express mera (mercuric ion reductase) and merb (organomercury lyase) transgenes in order to be used for the phytoremediation of mercury-contaminated soils. earlier studies with arabidopsis thaliana and nicotiana tabacum showed that this gene combination resulted in more efficient detoxification of organomercurial compounds than did merb alone, but neither species is optimal for long-term field applications. leaf dis ... | 2007 | 17309680 |
| production of transgenic strawberries by temporary immersion bioreactor system and verification by tail-pcr. | strawberry (fragaria x ananassa) is an economically important soft fruit crop with polyploid genome which complicates the breeding of new cultivars. for certain traits, genetic engineering offers a potential alternative to traditional breeding. however, many strawberry varieties are quite recalcitrant for agrobacterium-mediated transformation, and a method allowing easy handling of large amounts of starting material is needed. also the genotyping of putative transformants is challenging since th ... | 2007 | 17309794 |
| transient beta-glucuronidase expression in lily (lilium longflorum l.) pollen via wounding-assisted agrobacterium-mediated transformation. | a pollen-based transient expression system has been developed. lily pollen grains, wounded by vigorous shaking in the presence of aluminum oxide particles, were transformed by infiltration with agrobacterium tumefaciens lba4404 cells harboring the beta-glucuronidase (gus) gene construct, pbi121. in histochemical and fluorometric gus analysis, the wounding processes allowed efficient transformation and, in cdna blot hybridization, gus mrna synthesis was clearly detected. lily pollen with appropri ... | 2007 | 17310322 |
| living without fur: the subtlety and complexity of iron-responsive gene regulation in the symbiotic bacterium rhizobium and other alpha-proteobacteria. | the alpha-proteobacteria include several important genera, including the symbiotic n(2)-fixing "rhizobia", the plant pathogen agrobacterium, the mammalian pathogens brucella, bartonella as well as many others that are of environmental or other interest--including rhodobacter, caulobacter and the hugely abundant marine genus pelagibacter. only a few species--mainly different members of the rhizobia--have been analyzed directly for their ability to use and to respond to iron. these studies, howeve ... | 2007 | 17310401 |
| bacillus megaterium rhizobacteria promote growth and alter root-system architecture through an auxin- and ethylene-independent signaling mechanism in arabidopsis thaliana. | soil microorganisms are critical players in plant-soil interactions at the rhizosphere. we have identified a bacillus megaterium strain that promoted growth and development of bean (phaseolus vulgaris) and arabidopsis thaliana plants. we used arabidopsis thaliana as a model to characterize the effects of inoculation with b. megaterium on plant-growth promotion and postembryonic root development. b. megaterium inoculation caused an inhibition in primary-root growth followed by an increase in late ... | 2007 | 17313171 |
| production of soft rot resistant calla lily by expressing a ferredoxin-like protein gene (pflp) in transgenic plants. | an efficient protocol for the agrobacterium tumefaciens-mediated transformation of calla lily (zantedeschia elliottiana (w. wats.) engl. cultivar 'florex gold') is described. shoot basal discs were co-cultivated with a. tumefaciens c58c1 carrying a plasmid containing neomycin phosphotransferase (nptii) and plant ferredoxin-like protein (pflp) genes. after agrobacterium co-cultivation, the shoot basal discs were exposed to 100 mg l(-1) kanamycin for selection. twenty-eight out of 260 discs (10.8% ... | 2007 | 17033825 |
| agrobacterium tumefaciens and agrobacterium rhizogenes transformed roots of the parasitic plant triphysaria versicolor retain parasitic competence. | parasitic plants in the orobanchaceae invade roots of neighboring plants to rob them of water and nutrients. triphysaria is facultative parasite that parasitizes a broad range of plant species including maize and arabidopsis. in this paper we describe transient and stable transformation systems for triphysaria versicolor fischer and c. meyer. agrobacterium tumefaciens and agrobacterium rhizogenes were both able to transiently express a gus reporter in triphysaria seedlings following vacuum infil ... | 2007 | 17053892 |
| plant transformation by agrobacterium tumefaciens: modulation of single-stranded dna-vire2 complex assembly by vire1. | agrobacterium tumefaciens infects plant cells by the transfer of dna. a key factor in this process is the bacterial virulence protein vire2, which associates stoichiometrically with the transported single-stranded (ss) dna molecule (t-strand). as observed in vitro by transmission electron microscopy, vire2-ssdna readily forms an extended helical complex with a structure well suited to the tasks of dna protection and nuclear import. here we have elucidated the role of the specific molecular chape ... | 2007 | 17060320 |
| production and characterization of anti-(mucin muc1) single-domain antibody in tobacco (nicotiana tabacum cultivar xanthi). | members of the camelidae (camels, dromedaries, llamas, alpacas, guanacos and vicunas) are known to produce igs (immunoglobulins) devoid of light chains and ch1s (constant heavy-chain domains). the antigen-specific binding fragments of these heavy-chain antibodies therefore comprise one single domain (the so-called 'vhh') and are of great importance in biotechnological applications. to evaluate the expression and biological activity of sdabs (single-domain antibodies) in plants, which, on account ... | 2007 | 17073735 |
| contribution of invariant residues to the function of rgg family transcription regulators. | the rgg family of transcription regulators is widely distributed among gram-positive bacteria, yet how these proteins control transcription is poorly understood. using streptococcus pyogenes ropb as a model, we demonstrated that residues invariant among rgg-like regulators are critical for function and obtained evidence for a mechanism involving protein complex formation. | 2007 | 17098902 |
| earlier flowering induced by over-expression of co gene does not accompany increase of artemisinin biosynthesis in artemisia annua. | the early flowering gene constans (co) from arabidopsis thaliana was transferred into artemisia annua using the agrobacterium tumefaciens-mediated transformation system. the plant expression vector pbi co was constructed by inserting the co gene into the binary vector pbi121 under the control of camv 35s promoter. analyses of pcr, pcr southern blot, and southern blot revealed that the transgenic plants contained the foreign co gene. the results of rt-pct and rt-pcr southern blot suggested that t ... | 2007 | 17099845 |
| transgene-dependent incompatibility induced by introduction of the sk2:zpt2-10 chimeric gene in petunia. | in an attempt to functionally characterize a petunia zinc-finger gene zpt2-10, which is specifically expressed in style transmitting tissue, we fused its cdna downstream of the potato sk2 promoter (sk2:zpt2-10) and then introduced it into petunia hybrida. we found that some transformants had acquired altered traits in compatibility in mating; these were termed 'transgene-dependent incompatibility (tdi)'. these transgenic lines were fertile when self-pollinated or crossed with other tdi lines. in ... | 2007 | 17103023 |
| changes in morphological phenotypes and withanolide composition of ri-transformed roots of withania somnifera. | developmental variability was introduced into withania somnifera using genetic transformation by agrobacterium rhizogenes, with the aim of changing withasteroid production. inoculation of w. somnifera with a. rhizogenes strains lba 9402 and a4 produced typical transformed root lines, transformed callus lines, and rooty callus lines with simultaneous root dedifferentiation and redifferentiation. these morphologically distinct transformed lines varied in t-dna content, growth rates, and withastero ... | 2007 | 17103214 |
| engineering resistance to pvy in different potato cultivars in a marker-free transformation system using a 'shooter mutant' a. tumefaciens. | in this work, potato virus y (pvy) resistant potatoes were generated using an environmentally safe construct. for this purpose, a 'shooter' mutant agrobacterium-based transformation system was used. the isopentenyl transferase gene (ipt) present on the ti plasmid of 'shooter' strains enhances shoot regeneration and can be used as a phenotypic selection marker. the introduced marker-free binary vector carried a hairpin construct derived from the coat protein gene of pvy-ntn strain in order to ind ... | 2007 | 17103215 |
| production of sirna targeted against tylcv coat protein transcripts leads to silencing of its expression and resistance to the virus. | the coat protein (cp) of tomato yellow leaf curl virus (tylcv), encoded by the v1 gene, is the only known component of the viral capsid. in addition, the cp plays a role in the virus transport into the host cell nucleus where viral genes are replicated and transcribed. in this study, we analyzed the effect of small interfering double-stranded rnas (sirnas), derived from an intron-hairpin rna (ihprna) construct and targeting the v1 gene product, on cp accumulation. transient assays involving agro ... | 2007 | 17103242 |
| overexpression of barley hva1 gene in creeping bentgrass for improving drought tolerance. | the objectives of this study were to test the feasibility of introducing barley hva1 gene, a lea3 member, into perennial grass species using the agrobacterium-mediated transformation technique and to determine whether heterologous expression of hva1 would alleviate water-deficit injury in grass species. creeping bentgrass (agrostis stolonifera var. palustris), a drought-intolerant grass species, was transformed transiently or stably using three different promoters in conjunction with the downstr ... | 2007 | 17106681 |
| rhizobium etli usda9032 engineered to produce a phenazine antibiotic inhibits the growth of fungal pathogens but is impaired in symbiotic performance. | phenazine production was engineered in rhizobium etli usda9032 by the introduction of the phz locus of pseudomonas chlororaphis o6. phenazine-producing r. etli was able to inhibit the growth of botrytis cinerea and fusarium oxysporum in vitro. black bean inoculated with phenazine-producing r. etli produced brownish fix(-) nodules. | 2007 | 17085692 |
| a cytokinin perception mutant colonized by rhizobium in the absence of nodule organogenesis. | in legumes, nod-factor signaling by rhizobia initiates the development of the nitrogen-fixing nodule symbiosis, but the direct cell division stimulus that brings about nodule primordia inception in the root cortex remains obscure. we showed that lotus japonicus plants homozygous for a mutation in the hyperinfected 1 (hit1) locus exhibit abundant infection-thread formation but fail to initiate timely cortical cell divisions in response to rhizobial signaling. we demonstrated that the correspondin ... | 2007 | 17110535 |
| directed evolution and structural analysis of n-carbamoyl-d-amino acid amidohydrolase provide insights into recombinant protein solubility in escherichia coli. | one of the greatest bottlenecks in producing recombinant proteins in escherichia coli is that over-expressed target proteins are mostly present in an insoluble form without any biological activity. dcase (n-carbamoyl-d-amino acid amidohydrolase) is an important enzyme involved in semi-synthesis of beta-lactam antibiotics in industry. in the present study, in order to determine the amino acid sites responsible for solubility of dcase, error-prone pcr and dna shuffling techniques were applied to r ... | 2007 | 17121498 |
| highly conserved residues asp-197 and his-250 in agp1 phytochrome control the proton affinity of the chromophore and pfr formation. | the mutants h250a and d197a of agp1 phytochrome from agrobacterium tumefaciens were prepared and investigated by different spectroscopic and biochemical methods. asp-197 and his-250 are highly conserved amino acids and are part of the hydrogen-bonding network that involves the chromophore. both substitutions cause a destabilization of the protonated chromophore in the pr state as revealed by resonance raman and uv-visible absorption spectroscopy. titration experiments demonstrate a lowering of t ... | 2007 | 17121858 |
| optimization of culture conditions and scale-up to pilot and plant scales for coenzyme q10 production by agrobacterium tumefaciens. | this report describes the optimization of culture conditions for coenzyme q(10) (coq(10)) production by agrobacterium tumefaciens kccm 10413, an identified high-coq(10)-producing strain (kim et al., korean patent. 10-0458818, 2002b). among the conditions tested, the ph and the dissolved oxygen (do) levels were the key factors affecting coq(10) production. when the ph and do levels were controlled at 7.0 and 0-10%, respectively, a dry cell weight (dcw) of 48.4 g l(-1) and a coq(10) production of ... | 2007 | 17124579 |
| functional expression of escherichia coli fhua gene in rhizobium spp. of cajanus cajan provides growth advantage in presence of fe3+: ferrichrome as iron source. | cajanus cajan rhizobial isolates were found to be unable to utilize iron bound to ferrichrome, desferrioxamine b or rhodotorulic acid, all being hydroxamate type siderophores. a broad host range expression vector containing the escherichia coli fhua gene, encoding the outer membrane receptor for fe-ferrichrome, was constructed. the plasmid construct (pgr1), designed to express fhua under the lac promoter of e. coli, complemented e. coli mb97 deltafhua mutant for ferri-ferrichrome utilization and ... | 2007 | 17136381 |
| modulation of the venation pattern of cotyledons of transgenic tobacco for the tumorigenic 6b gene of agrobacterium tumefaciens ake10. | neoplastic plant-tissue formation, termed crown gall disease, is induced on infection with agrobacterium tumefaciens. the tumorous tissues develop an extensive vascular system, with a venation pattern distinct from that of native host plants. we report here that the plant-tumorigenic 6b gene of the a. tumefaciens strain ake10 is capable of inducing extensive vein formation in transgenic tobacco seedlings with distinct pattern formation. unlike the wild-type cotyledons, transgenic cotyledons had ... | 2007 | 17136474 |
| use of dna marker to select well-adapted phaseolus-symbionts strains under acid conditions and high temperature. | soil acidity and high temperature contribute to the failure of nodulation in the common bean. it is therefore urgent to select strains with a high competitive ability under these stress conditions. two egyptian rhizobium etli strains, ebri 2 and ebri 26, were examined against rhizobium tropici ciat 899g labeled with the gus (beta-glucuronidase) reporter gene. ebri 2 and ebri 26 were less competitive than ciat 899g under acid conditions with both the egyptian cultivar giza 3 and the colombian cul ... | 2007 | 17136573 |
| towards the elucidation of am-specific transcription in medicago truncatula. | roots of most plants form a mutualistic interaction with arbuscular mycorrhiza (am) fungi. during the symbiosis, drastic morphological and physiological changes occur in the host plant root system. these changes are likely to be controlled by a specific genetic program of the plant. the legume medicago truncatula is a model system widely used to elucidate this program. a number of loci required for am-development have been identified by the analysis of m. truncatula mutants; however, the genes i ... | 2007 | 17141285 |
| transposition-based plant transformation. | agrobacterium t-dnas were used to deliver transposable dissociation (ds) elements into the nuclei of potato (solanum tuberosum) cells. a double-selection system was applied to enrich for plants that only contained a transposed ds element. this system consisted of a positive selection for the neomycin phosphotransferase (nptii) gene positioned within ds followed by a negative selection against stable integration of the cytosine deaminase (coda) gene-containing t-dna. sixteen of 29 transgenic plan ... | 2007 | 17142486 |
| in planta akt2 subunits constitute a ph- and ca2+-sensitive inward rectifying k+ channel. | heterologous expression of plant genes in yeast and animal cells represents a common approach to study plant ion channels. when expressed in xenopus oocytes and cos cells the arabidopsis shaker-like k+ channel, akt2 forms a weakly voltage-dependent channel, blocked by ca2+ and protons. channels with these characteristics, however, were not found in akt2-expressing arabidopsis cell types. to understand this phenomenon, we employed agrobacterium-mediated transient transformation to functionally ch ... | 2007 | 17146665 |
| strain-specific salt tolerance and osmoregulatory mechanisms in azospirillum brasilense. | salinity stress inhibits the growth and nitrogen fixation ability of the plant growth-promoting rhizobacterium azospirillum brasilense. five strains of a. brasilense were isolated from the rhizosphere of indian cereals and grasses and identified on the basis of their phenotypic features and 16s rrna gene sequence. the five indian isolates and two standard strains of a. brasilense, sp7 and cd, showed notable differences in growth, acetylene-reducing activity under salt stress, and ability to take ... | 2007 | 17156127 |
| genetic transformation and gene silencing mediated by multiple copies of a transgene in eastern white pine. | an efficient transgenic eastern white pine (pinus strobus l.) plant regeneration system has been established using agrobacterium tumefaciens strain gv3850-mediated transformation and the green fluorescent protein (gfp) gene as a reporter in this investigation. stable integration of transgenes in the plant genome of pine was confirmed by polymerase chain reaction (pcr), southern blot, and northern blot analyses. transgene expression was analysed in pine t-dna transformants carrying different numb ... | 2007 | 17158108 |
| biochemical and genetic analysis of the gamma-resorcylate (2,6-dihydroxybenzoate) catabolic pathway in rhizobium sp. strain mtp-10005: identification and functional analysis of its gene cluster. | we identified a gene cluster that is involved in the gamma-resorcylate (2,6-dihydroxybenzoate) catabolism of the aerobic bacterium rhizobium sp. strain mtp-10005. the cluster consists of the grardafcbek genes, and graa, grab, grac, and grad were heterologously expressed in escherichia coli. enzymological studies showed that grad, graa, grac, and grab encode the reductase (grad) and oxygenase (graa) components of a resorcinol hydroxylase (ec 1.14.13.x), a maleylacetate reductase (grac) (ec 1.3.1. ... | 2007 | 17158677 |
| the major chemotaxis gene cluster of rhizobium leguminosarum bv. viciae is essential for competitive nodulation. | rhizobium leguminosarum biovar viciae strain 3841 is a motile alpha-proteobacterium that can establish a nitrogen-fixing symbiosis within the roots of pea plants. in order to determine the contribution of chemotaxis to the lifestyle of r. leguminosarum, we have characterized the function of two chemotaxis gene clusters (che1 and che2) in controlling motility behaviour. we have found that both chemotaxis gene clusters modulate the motility swimming bias of r. leguminosarum cells and that the che1 ... | 2007 | 17163982 |
| the usefulness of the gfp reporter gene for monitoring agrobacterium-mediated transformation of potato dihaploid and tetraploid genotypes. | potato is one of the main targets for genetic improvement by gene transfer. the aim of the present study was to establish a robust protocol for the genetic transformation of three dihaploid and four economically important cultivars of potato using agrobacterium tumefaciens carrying the in vivo screenable reporter gene for green fluorescent protein (gfp) and the marker gene for neomycin phosphotransferase (nptii). stem and leaf explants were used for transformation by agrobacterium tumefaciens st ... | 2007 | 17165042 |
| stable agrobacterium-mediated genetic transformation of london plane tree (platanus acerifolia willd.). | london plane tree (platanus acerifolia willd.) is an important tree in urban landscaping but it suffers from a number of negative traits which genetic engineering could be used to address. as with many woody species, p. acerifolia has appeared recalcitrant to genetic transformation. however, the recent development of a method for regenerating shoots from p. acerifolia leaf explants suggests that such material could be a target for gene-transfer. using an agrobacterium tumefaciens strain in which ... | 2007 | 17165043 |
| the rolb gene-induced overproduction of resveratrol in vitis amurensis transformed cells. | resveratrol is a stilbene, which prevents carcinogenesis at stages of tumor initiation, promotion and progression. in the present investigation, we developed cell cultures of wild-growing grape (vitis amurensis rupr.). the cultures produced low levels of resveratrol, up to 0.026% dry wt., i.e., comparable to levels reported for other plant cell cultures previously established. different methods commonly used to increase secondary metabolite production (cell selection, elicitor treatments and add ... | 2007 | 17166613 |
| agrobacterium-mediated transformation to create an insertion library in magnaporthe grisea. | magnaporthe grisea is the causal agent of rice blast disease and represents a model organism for the study of fungal plant-pathogen interactions. pathogenicity is a complex phenotype, which is carefully orchestrated by the fungus and begins with recognition and infection of the host plant, followed by growth within the plant cells, and finally dissemination to the next host and continuation of the fungal life cycle. certain genes must condition the ability of a pathogenic fungus to infect and ca ... | 2007 | 17172744 |
| use of rna interference to dissect defense-signaling pathways in rice. | the rna interference (rnai) technique is a powerful tool to suppress gene expression and has been widely used for functional discovery of eukaryotic genes. to dissect defense-signaling pathways in rice, it is important to generate a series of rice mutant lines deficient in or insensitive to major signal molecules such as jasmonic acid and ethylene. here we describe an rnai protocol for generating and characterizing transgenic gene-silencing lines defective in rice jasmonic acid signaling. the rn ... | 2007 | 17172753 |
| virus-induced gene silencing in plant roots. | virus-induced gene silencing (vigs) has been used as a quick and easy tool to assess gene function in plants. the virus, carrying a portion of an endogenous gene, triggers a homology-based defense mechanism when introduced into plants. infection with the modified virus results in gene-specific transcript degradation. several virus-based vectors have been developed for use in vigs. one of these virus vectors, tobacco rattle virus (trv), has a large host range and is transmitted by phytopathogenic ... | 2007 | 17172754 |
| the symbiotic ion channel homolog dmi1 is localized in the nuclear membrane of medicago truncatula roots. | legumes utilize a common signaling pathway to form symbiotic associations both with rhizobial bacteria and arbuscular mycorrhizal fungi. the perception of microbial signals is believed to take place at the plasma membrane, activating a cascade that converges on the nucleus where transcriptional reprogramming facilitates the symbioses. forward genetic strategies have identified genes in this signaling pathway including medicago truncatula dmi1 (doesn't make infections 1) that encodes a putative i ... | 2007 | 17173544 |
| mesorhizobium albiziae sp. nov., a novel bacterium that nodulates albizia kalkora in a subtropical region of china. | a novel mesorhizobium group associated with albizia kalkora [wang et al. (2006), syst appl microbiol 29, 502-517] was further characterized. the seven strains in this group showed similar protein patterns and were different from defined mesorhizobium species in sds-page of whole-cell proteins. the representative strain ccbau 61158(t) formed a novel mesorhizobium lineage in phylogenetic analyses of 16s rrna, atpd, glnii and nifh genes. however, its nodc gene sequence was more similar to that of r ... | 2007 | 17551028 |
| establishment of an efficient agrobacterium tumefaciens-mediated leaf disc transformation of thellungiella halophila. | thellungiella halophila is a salt-tolerant close relative of arabidopsis, which is adopted as a halophytic model for stress tolerance research. we established an agrobacterium tumefaciens-mediated transformation procedure for t. halophila. leaf explants of t. halophila were incubated with a. tumefaciens strain eha105 containing a binary vector pcambia1301 with the hpt gene as a selectable marker for hygromycin resistance and an intron-containing beta-glucuronidase gene as a reporter gene. follow ... | 2007 | 17551729 |
| highly efficient agrobacterium-mediated transformation of embryogenic cell suspensions of musa acuminata cv. mas (aa) via a liquid co-cultivation system. | a high efficient protocol of agrobacterium-mediated transformation of musa acuminata cv. mas (aa), a major banana variety of the south east asia region, was developed in this study. male-flower-derived embryogenic cell suspensions (ecs) were co-cultivated in liquid medium with agrobacterium strain eha105 harboring a binary vector pcambia2301 carrying nptii and gusa gene in the t-dna. depending upon conditions and duration of co-cultivation in liquid medium, 0-490 transgenic plants per 0.5 ml pac ... | 2007 | 17551731 |
| tryptophan-dependent production of indole-3-acetic acid (iaa) affects level of plant growth promotion by bacillus amyloliquefaciens fzb42. | phytohormone-like acting compounds previously have been suggested to be involved in the phytostimulatory action exerted by the plant-beneficial rhizobacterium bacillus amyloliquefaciens fzb42. analyses by high-performance liquid chromatography and gas chromatography-mass spectrometry performed with culture filtrates of fzb42 demonstrated the presence of indole-3-acetic acid (iaa), corroborating it as one of the pivotal plant-growth-promoting substances produced by this bacterium. in the presence ... | 2007 | 17555270 |
| involvement of a soybean atp-binding cassette-type transporter in the secretion of genistein, a signal flavonoid in legume-rhizobium symbiosis. | legume plants have an ability to fix atmospheric nitrogen into nutrients via symbiosis with soil microbes. as the initial event of the symbiosis, legume plants secrete flavonoids into the rhizosphere to attract rhizobia. secretion of flavonoids is indispensable for the establishment of symbiotic nitrogen fixation, but almost nothing is known about the membrane transport mechanism of flavonoid secretion from legume root cells. in this study, we performed biochemical analyses to characterize the t ... | 2007 | 17556512 |
| sensitive whole-cell biosensor suitable for detecting a variety of n-acyl homoserine lactones in intact rhizosphere microbial communities. | to investigate quorum sensing in rhizosphere soil, a whole-cell biosensor, agrobacterium tumefaciens(pahl-ice), was constructed. the biosensor responded to all n-acyl homoserine lactones (ahls) tested, except c(4) homoserine lactone, with a minimum detection limit of 10(-12) m, as well as to both exogenously added ahls and ahl-producing bacterial strains in soil. this highly sensitive biosensor reveals for the first time the increased ahl availability in intact rhizosphere microbial communities ... | 2007 | 17400771 |
| the novel alkali tolerance function of tfxg in sinorhizobium meliloti. | tfxg, one of the tfxabcdefg cluster genes that code for trifolitoxin (tfx) production, was initially described in rhizobium leguminosarum bv. trifolii t24. although several genes in the tfx family have functions related to tfx production or resistance to tfx, the function of tfxg is largely unknown. using cdna-amplified fragment length polymorphism (cdna-aflp) analysis, we found that expression of the tfxg gene dramatically increased under alkaline culture conditions in sinorhizobium meliloti cc ... | 2007 | 17566711 |
| context analysis of termination codons in mrna that are recognized by plant nmd. | the nonsense-mediated mrna decay (nmd) system is an rna surveillance system that degrades mrnas possessing premature translation termination codons (ptcs). although nmd factors are well conserved in eukaryotes, it is speculated that the contexts of those termination codons that are subject to nmd are different depending on the organism. context analysis of termination codons that are recognized by the plant nmd system would clarify nmd target mrnas in plants, and contribute to our understanding ... | 2007 | 17567637 |
| the pyda-pydb fusion gene produces an active dioxygenase-hydrolase that degrades 3-hydroxy-4-pyridone, an intermediate of mimosine metabolism. | the objective of this research was to construct a pyda-pydb hybrid gene that encodes a functional dioxygenase-hydrolase (pyda-pydb) fusion protein for degradation of 3-hydroxy-4-pyridone (hp). hp is an intermediate in both synthesis and degradation of mimosine, a toxic amino acid produced by the tree legume leucaena leucocephala. computer-generated models of the fusion proteins suggested that joining of pyda and pydb with 0, 3, or 7 glycine residues as a linker should produce a functional pyda-p ... | 2007 | 17390132 |
| physiological and expression analyses of agrobacterium tumefaciens trxa, encoding thioredoxin. | exposure of agrobacterium tumefaciens to menadione, cumene hydroperoxide, and diamide strongly induced trxa expression. the trxa mutant showed a reduction in the aerobic growth rate and plating efficiency and was cytochrome c oxidase negative. atypically, the mutant has decreased resistance to menadione but an increased h2o2 resistance phenotype. | 2007 | 17573482 |
| molecular analysis of agrobacterium t-dna integration in tomato reveals a role for left border sequence homology in most integration events. | studies in several plants have shown that agrobacterium tumefaciens t-dna can integrate into plant chromosomal dna by different mechanisms involving single-stranded (ss) or double-stranded (ds) forms. one mechanism requires sequence homology between plant target and sst-dna border sequences and another double-strand-break repair in which preexisting chromosomal dsbs "capture" dst-dnas. to learn more about t-dna integration in solanum lycopersicum we characterised 98 t-dna/plant dna junction sequ ... | 2007 | 17574477 |
| production and secretion of resveratrol in hairy root cultures of peanut. | resveratrol and its derivatives are natural stilbenes associated with many health benefits that include those conferred by their antioxidant and anticancer properties. while stilbenes can be recovered as an extract from a selected number of plants, these products are not suitable for many applications in the food/pharmaceutical sectors due to high levels of impurities as well as the overall low concentration of resveratrol and its derivatives in the extract. to deliver a highly defined and enric ... | 2007 | 17574636 |
| high-speed gel microelectrophoresis, a new and easy approach for detection of pcr-amplified microbial dna from environmental and clinical samples in microgels using conventional equipment. | microelectrophoresis allows the detection of dna bands using minimal amounts of sample in a short time, but commonly requires the use of special equipment which is not available in all laboratories. this fact has limited the application of this technique in microbiology despite its advantages. in this work, we describe a new approach to perform gel microelectrophoresis, named high-speed gel microelectrophoresis (hsgme), and its application for rapid detection of bacteria, protozoa and viruses in ... | 2007 | 17576229 |
| [fruit-specific rnai-mediated lcy gene enhances content of lycopene in tomatoes silencing]. | tomatoes ( lycopersicon esculentum mill.) are the principal dietary source of lycopene which is one of carotenoid and is highly beneficial in preventing some diseases such as the cancer and the heart disease. suppressing the expression of lcy gene, the main gene regulating the transformation of the lycopene, is a convenient and effective way to enhance the content of lycopene. the primers were designed according to the gene sequence(u46919)and (x86452) in genbank. the fruit-specific promoter--ph ... | 2007 | 17577988 |
| treatment of chickpea with rhizobium isolates enhances the expression of phenylpropanoid defense-related genes in response to infection by fusarium oxysporum f. sp. ciceris. | differential expression of phenylalanine ammonia-lyase (pal), chalcone synthase (chs) and isoflavone reductase (ifr) genes involved in phenylpropanoids metabolism was investigated using northern blot analyses in chickpea seedlings bacterized with rhizobium isolates (pchdms and pch43) and further challenged with fusarium oxysporum f. sp. ciceris (foc) race 0. gene activation patterns in the moderately resistant accession inrat87/1 were compared with those exhibited by the susceptible accession il ... | 2007 | 17544286 |
| effect of chromatin upon agrobacterium t-dna integration and transgene expression. | agrobacterium tumefaciens transfers dna (t-dna) to plant cells, where it integrates into the plant genome. little is known about how t-dna chooses sites within the plant chromosome for integration. previous studies indicated that t-dna preferentially integrates into transcriptionally active regions of the genome, especially in 5'-promoter regions. this would make sense, considering that chromatin structure surrounding active promoters may be more "open" and accessible to foreign dna. however, re ... | 2007 | 17544520 |
| a systematic analysis of t-dna insertion events in magnaporthe oryzae. | we describe here the analysis of random t-dna insertions that were generated as part of a large-scale insertional mutagenesis project for magnaporthe oryzae. chromosomal regions flanking t-dna insertions were rescued by inverse pcr, sequenced and used to search the m. oryzae genome assembly. among the 175 insertions for which at least one flank was rescued, 137 had integrated in single-copy regions of the genome, 17 were in repeated sequences, one had no match to the genome, and the remainder we ... | 2007 | 17544743 |
| agrobacterium tumefaciens fur has important physiological roles in iron and manganese homeostasis, the oxidative stress response, and full virulence. | in agrobacterium tumefaciens, the balance between acquiring enough iron and avoiding iron-induced toxicity is regulated in part by fur (ferric uptake regulator). a fur mutant was constructed to address the physiological role of the regulator. atypically, the mutant did not show alterations in the levels of siderophore biosynthesis and the expression of iron transport genes. however, the fur mutant was more sensitive than the wild type to an iron chelator, 2,2'-dipyridyl, and was also more resist ... | 2007 | 17545320 |