| development of a high throughput transformation system for insertional mutagenesis in magnaporthe oryzae. | towards the goal of disrupting all genes in the genome of magnaporthe oryzae and identifying their function, a collection of >55,000 random insertion lines of m. oryzae strain 70-15 were generated. all strains were screened to identify genes involved in growth rate, conidiation, pigmentation, auxotrophy, and pathogenicity. here, we provide a description of the high throughput transformation and analysis pipeline used to create our library. transformed lines were generated either by cacl(2)/peg t ... | 2007 | 17600737 |
| identification of a biosynthetic gene cluster and the six associated lipopeptides involved in swarming motility of pseudomonas syringae pv. tomato dc3000. | pseudomonas species are known to be prolific producers of secondary metabolites that are synthesized wholly or in part by nonribosomal peptide synthetases. in an effort to identify additional nonribosomal peptides produced by these bacteria, a bioinformatics approach was used to "mine" the genome of pseudomonas syringae pv. tomato dc3000 for the metabolic potential to biosynthesize previously unknown nonribosomal peptides. herein we describe the identification of a nonribosomal peptide biosynthe ... | 2007 | 17601782 |
| reciprocal phosphorylation and glycosylation recognition motifs control ncapp1 interaction with pumpkin phloem proteins and their cell-to-cell movement. | in plants, cell-to-cell trafficking of non-cell-autonomous proteins (ncaps) involves protein-protein interactions, and a role for posttranslational modification has been implicated. in this study, proteins contained in pumpkin (cucurbita maxima cv big max) phloem sap were used as a source of ncaps to further explore the molecular basis for selective ncap trafficking. protein overlay assays and coimmunoprecipitation experiments established that phosphorylation and glycosylation, on both nicotiana ... | 2007 | 17601822 |
| lpa2 is required for efficient assembly of photosystem ii in arabidopsis thaliana. | to elucidate the molecular mechanism of photosystem ii (psii) assembly, we characterized the low psii accumulation2 (lpa2) mutant of arabidopsis thaliana, which is defective in the accumulation of psii supercomplexes. the levels and processing patterns of the rnas encoding the psii subunits are unaltered in the mutant. in vivo protein-labeling experiments showed that the synthesis of cp43 (for chlorophyll a binding protein) was greatly reduced, but cp47, d1, and d2 were synthesized at normal rat ... | 2007 | 17601825 |
| bacterial cyclic beta-(1,2)-glucan acts in systemic suppression of plant immune responses. | although cyclic glucans have been shown to be important for a number of symbiotic and pathogenic bacterium-plant interactions, their precise roles are unclear. here, we examined the role of cyclic beta-(1,2)-glucan in the virulence of the black rot pathogen xanthomonas campestris pv campestris (xcc). disruption of the xcc nodule development b (ndvb) gene, which encodes a glycosyltransferase required for cyclic glucan synthesis, generated a mutant that failed to synthesize extracellular cyclic be ... | 2007 | 17601826 |
| the arabidopsis mate transporter tt12 acts as a vacuolar flavonoid/h+ -antiporter active in proanthocyanidin-accumulating cells of the seed coat. | phenotypic characterization of the arabidopsis thaliana transparent testa12 (tt12) mutant encoding a membrane protein of the multidrug and toxic efflux transporter family, suggested that tt12 is involved in the vacuolar accumulation of proanthocyanidin precursors in the seed. metabolite analysis in tt12 seeds reveals an absence of flavan-3-ols and proanthocyanidins together with a reduction of the major flavonol quercetin-3-o-rhamnoside. the tt12 promoter is active in cells synthesizing proantho ... | 2007 | 17601828 |
| gliotoxin is a virulence factor of aspergillus fumigatus: glip deletion attenuates virulence in mice immunosuppressed with hydrocortisone. | gliotoxin is an immunosuppressive mycotoxin long suspected to be a potential virulence factor of aspergillus fumigatus. recent studies using mutants lacking gliotoxin production, however, suggested that the mycotoxin is not important for pathogenesis of a. fumigatus in neutropenic mice resulting from treatment with cyclophosphomide and hydrocortisone. in this study, we report on the pathobiological role of gliotoxin in two different mouse strains, 129/sv and balb/c, that were immunosuppressed by ... | 2007 | 17601876 |
| reconstructing the evolution of the mitochondrial ribosomal proteome. | for production of proteins that are encoded by the mitochondrial genome, mitochondria rely on their own mitochondrial translation system, with the mitoribosome as its central component. using extensive homology searches, we have reconstructed the evolutionary history of the mitoribosomal proteome that is encoded by a diverse subset of eukaryotic genomes, revealing an ancestral ribosome of alpha-proteobacterial descent that more than doubled its protein content in most eukaryotic lineages. we obs ... | 2007 | 17604309 |
| genome-wide analysis of agrobacterium t-dna integration sites in the arabidopsis genome generated under non-selective conditions. | previous work from numerous laboratories has suggested that integration of agrobacterium tumefaciens t-dna into the plant genome occurs preferentially in promoter or transcriptionally active regions. however, all of these studies were conducted on plants recovered from selective conditions requiring the expression of transgenes. the conclusions of these studies may therefore have been biased because of the selection of transformants. in this study, we investigated t-dna integration sites in the ... | 2007 | 17605756 |
| the plant signal salicylic acid shuts down expression of the vir regulon and activates quormone-quenching genes in agrobacterium. | agrobacterium tumefaciens is capable of transferring and integrating an oncogenic t-dna (transferred dna) from its tumor-inducing (ti) plasmid into dicotyledonous plants. this transfer requires that the virulence genes (vir regulon) be induced by plant signals such as acetosyringone in an acidic environment. salicylic acid (sa) is a key signal molecule in regulating plant defense against pathogens. however, how sa influences agrobacterium and its interactions with plants is poorly understood. he ... | 2007 | 17606909 |
| gene inactivation mediated by agrobacterium tumefaciens in the filamentous fungi metarhizium anisopliae. | the list of fungal species with known complete genome and/or expressed sequence tag collections is extending rapidly during the last couple of years. postgenomic gene function assignment is an obvious follow-up and depends on methodologies to test gene function in vivo. one of such methods is the generation of null mutants via homologous recombination at the wild-type loci by using inactivation cassettes. in this paper, the ability of agrobacterium tumefaciens to genetically transform filamentou ... | 2007 | 17607574 |
| hypericin and hyperforin production in st. john's wort in vitro culture: influence of saccharose, polyethylene glycol, methyl jasmonate, and agrobacterium tumefaciens. | influence of saccharose in the presence or absence of polyethylene glycol (peg), methyl jasmonate, and an inactivated bacterial culture of agrobacterium tumefaciens in cultivation medium on morphology of hypericum perforatum l. and production of hypericin and hyperforin was studied under in vitro conditions. production of hypericin and hyperforin was influenced by the presence of different concentrations of saccharose (10-30 g l(-1)) in cultivation medium. addition of peg (1.25-5 g l(-1)) in the ... | 2007 | 17608493 |
| effects of osmotic stress on antioxidant enzymes activities in leaf discs of psag12-ipt modified gerbera. | leaf senescence is often caused by water deficit and the chimeric gene p(sag12)-ipt is an auto-regulated gene delaying leaf senescence. using in vitro leaf discs culture system, the changes of contents of chlorophylls, carotenoids, soluble protein and thiobarbituric acid reactive substance (tbars) and antioxidant enzymes activities were investigated during leaf senescence of p(sagl2)-ipt modified gerbera induced by osmotic stress compared with the control plant (wild type). leaf discs were incub ... | 2007 | 17610324 |
| edr2 negatively regulates salicylic acid-based defenses and cell death during powdery mildew infections of arabidopsis thaliana. | the hypersensitive necrosis response (hr) of resistant plants to avirulent pathogens is a form of programmed cell death in which the plant sacrifices a few cells under attack, restricting pathogen growth into adjacent healthy tissues. in spite of the importance of this defense response, relatively little is known about the plant components that execute the cell death program or about its regulation in response to pathogen attack. | 2007 | 17612410 |
| sub-picosecond mid-infrared spectroscopy of phytochrome agp1 from agrobacterium tumefaciens. | the photoinduced primary reaction of the biliverdin binding phytochrome agp1 (agp1-bv) from agrobacterium tumefaciens was investigated by sub-picosecond time-resolved vis pump-ir probe spectroscopy. three time constants of tau(1)=0.7+/-0.05 ps, tau(2)=3.3+/-0.2 ps and tau(3)=33.3+/-1.5 ps could be isolated from the dynamics of structurally specific marker bands of the bv chromophore. these results together with those of accompanying sub-picosecond vis pump-vis probe spectroscopy allow the extens ... | 2007 | 17614346 |
| infection and coaccumulation of tobacco mosaic virus proteins alter microrna levels, correlating with symptom and plant development. | infections by plant virus generally cause disease symptoms by interfering with cellular processes. here we demonstrated that infection of nicotiana tabacum (n.t) by plant viruses representative of the tobamoviridae, potyviridae, and potexviridae families altered accumulation of certain micrornas (mirnas). a correlation was observed between symptom severity and alteration in levels of mirnas 156, 160, 164,166, 169, and 171 that is independent of viral posttranscriptional gene silencing suppressor ... | 2007 | 17615233 |
| highly efficient virus-induced gene silencing (vigs) in california poppy (eschscholzia californica): an evaluation of vigs as a strategy to obtain functional data from non-model plants. | eschscholzia californica (california poppy) is an emerging model plant for 'evo-devo' studies from the basal eudicot clade of papaveraceae. california poppy has a relatively small genome, a short life cycle and, most importantly, it is amenable for transformation. however, since this transformation protocol is time consuming, virus-induced gene silencing (vigs) was evaluated as a fast method to obtain functional data for california poppy genes. | 2007 | 17616562 |
| the tormoz gene encodes a nucleolar protein required for regulated division planes and embryo development in arabidopsis. | embryogenesis in arabidopsis thaliana is marked by a predictable sequence of oriented cell divisions, which precede cell fate determination. we show that mutation of the tormoz (toz) gene yields embryos with aberrant cell division planes and arrested embryos that appear not to have established normal patterning. the defects in toz mutants differ from previously described mutations that affect embryonic cell division patterns. longitudinal division planes of the proembryo are frequently replaced ... | 2007 | 17616738 |
| characterization and host range determination of soybean super virulent agrobacterium tumefaciens kat23. | agrobacterium tumefaciens kat23 isolated from peach root causes crown gall disease in a number of grain legume plants, including the common bean (phaseolus vulgaris) and soybean (glycine max). kat23 caused tumor formation in each of these plants more effectively than strain c58. biotype determination suggested that this strain is biotype ii. kat23 was able to utilize nopaline as a carbon source. partial sequence analysis indicated that kat23 harbors a nopaline-type ti plasmid, designated ptikat2 ... | 2007 | 17617710 |
| maize lc transcription factor enhances biosynthesis of anthocyanins, distinct proanthocyanidins and phenylpropanoids in apple (malus domestica borkh.). | flavonoids are a large family of polyphenolic compounds with manifold functions in plants. present in a wide range of vegetables and fruits, flavonoids form an integral part of the human diet and confer multiple health benefits. here, we report on metabolic engineering of the flavonoid biosynthetic pathways in apple (malus domestica borkh.) by overexpression of the maize (zea mays l.) leaf colour (lc) regulatory gene. the lc gene was transferred into the m. domestica cultivar holsteiner cox via ... | 2007 | 17618453 |
| crystallization and preliminary x-ray diffraction analysis of the hyperthermophilic sulfolobus solfataricus phosphotriesterase. | organophosphates constitute the largest class of insecticides used worldwide and some of them are potent nerve agents. consequently, organophosphate-degrading enzymes are of paramount interest as they could be used as bioscavengers and biodecontaminants. phosphotriesterases (ptes) are capable of hydrolyzing these toxic compounds with high efficiency. a distant and hyperthermophilic representative of the pte family was cloned from the archeon sulfolobus solfataricus mt4, overexpressed in escheric ... | 2007 | 17620708 |
| crystallization and preliminary x-ray analysis of bigr, a transcription repressor from xylella fastidiosa involved in biofilm formation. | bigr (biofilm growth-associated repressor) is a novel repressor protein that regulates the transcription of an operon implicated in biofilm growth in both xylella fastidiosa and agrobacterium tumefaciens. this protein binds to a palindromic ta-rich element located in the promoter of the bigr operon and strongly represses transcription of the operon. bigr contains a helix-turn-helix (hth) domain that is found in some members of the arsr/smtb family of metal sensors, which control metal resistance ... | 2007 | 17620720 |
| inhibition of the gene expression for granule-bound starch synthase i by rna interference in sweet potato plants. | granule-bound starch synthase i (gbssi) is one of the key enzymes catalyzing the formation of amylose, a linear alpha(1,4)d-glucan polymer, from adp-glucose. amylose-free transgenic sweet potato plants were produced by inhibiting sweet potato gbssi gene expression through rna interference. the gene construct consisting of an inverted repeat of the first exon separated by intron 1 of gbssi driven by the camv 35s promoter was integrated into the sweet potato genome by agrobacterium tumefaciens-med ... | 2007 | 17622537 |
| tomato mapks lempk1, lempk2, and lempk3 function in the systemin-mediated defense response against herbivorous insects. | systemin is a wound-signaling peptide that mediates defenses of tomato plants against herbivorous insects. perception of systemin by the membrane-bound receptor sr160 results in activation of mapks, synthesis of jasmonic acid (ja), and expression of defense genes. to test the function of mapks in the response to systemin, we used virus-induced gene silencing (vigs) in plants that overexpress the systemin precursor prosystemin (35s::prosys plants). these transgenic plants accumulate high levels o ... | 2007 | 17623784 |
| functional and structural characterization of the catalytic domain of the starch synthase iii from arabidopsis thaliana. | glycogen and starch are the major energy storage compounds in most living organisms. the metabolic pathways leading to their synthesis involve the action of several enzymes, among which glycogen synthase (gs) or starch synthase (ss) catalyze the elongation of the alpha-1,4-glucan backbone. at least five ss isoforms were described in arabidopsis thaliana; it has been reported that the isoform iii (ssiii) has a regulatory function on the synthesis of transient plant starch. the catalytic c-termina ... | 2008 | 17623838 |
| the pp2c-type phosphatase ap2c1, which negatively regulates mpk4 and mpk6, modulates innate immunity, jasmonic acid, and ethylene levels in arabidopsis. | wound signaling pathways in plants are mediated by mitogen-activated protein kinases (mapks) and stress hormones, such as ethylene and jasmonates. in arabidopsis thaliana, the transmission of wound signals by mapks has been the subject of detailed investigations; however, the involvement of specific phosphatases in wound signaling is not known. here, we show that ap2c1, an arabidopsis ser/thr phosphatase of type 2c, is a novel stress signal regulator that inactivates the stress-responsive mapks ... | 2007 | 17630279 |
| role of laea in the regulation of alb1, glip, conidial morphology, and virulence in aspergillus fumigatus. | the alb1 (pksp) gene has been reported as a virulence factor controlling the pigmentation and morphology of conidia in aspergillus fumigatus. a recent report suggested that laea regulates alb1 expression and conidial morphology but not pigmentation in the a. fumigatus strain af293. laea has also been reported to regulate the synthesis of secondary metabolites, such as gliotoxin. we compared the role of laea in the regulation of conidial morphology and the expression of alb1 and glip in strains b ... | 2007 | 17630330 |
| characterization of agmat2, a plasma membrane mannitol transporter from celery, expressed in phloem cells, including phloem parenchyma cells. | a second mannitol transporter, agmat2, was identified in celery (apium graveolens l. var. dulce), a species that synthesizes and transports mannitol. this transporter was successfully expressed in two different heterologous expression systems: baker's yeast (saccharomyces cerevisiae) cells and tobacco (nicotiana tabacum) plants (a non-mannitol-producing species). data indicated that agmat2 works as an h(+)/mannitol cotransporter with a weak selectivity toward other polyol molecules. when express ... | 2007 | 17631523 |
| the arabidopsis bap1 and bap2 genes are general inhibitors of programmed cell death. | here we identify the bap1 and bap2 genes of arabidopsis (arabidopsis thaliana) as general inhibitors of programmed cell death (pcd) across the kingdoms. these two homologous genes encode small proteins containing a calcium-dependent phospholipid-binding c2 domain. bap1 and its functional partner bon1 have been shown to negatively regulate defense responses and a disease resistance gene snc1. genetic studies here reveal an overlapping function of the bap1 and bap2 genes in cell death control. the ... | 2007 | 17631528 |
| virb1* promotes t-pilus formation in the vir-type iv secretion system of agrobacterium tumefaciens. | the vir-type iv secretion system of agrobacterium is assembled from 12 proteins encoded by the virb operon and vird4. virb1 is one of the least-studied proteins encoded by the virb operon. its n terminus is a lytic transglycosylase. the c-terminal third of the protein, virb1*, is cleaved from virb1 and secreted to the outside of the bacterial cell, suggesting an additional function. we show that both nopaline and octopine strains produce abundant amounts of virb1* and perform detailed studies on ... | 2007 | 17631630 |
| in vivo oligomerization of the f conjugative coupling protein trad. | type iv secretory systems are a group of bacterial transporters responsible for the transport of proteins and nucleic acids directly into recipient cells. such systems play key roles in the virulence of some pathogenic organisms and in conjugation-mediated horizontal gene transfer. many type iv systems require conserved "coupling proteins," transmembrane polypeptides that are critical for transporting secreted substrates across the cytoplasmic membrane of the bacterium. in vitro evidence suggest ... | 2007 | 17631633 |
| the autotransporter esterase esta of pseudomonas aeruginosa is required for rhamnolipid production, cell motility, and biofilm formation. | pseudomonas aeruginosa pao1 produces the biodetergent rhamnolipid and secretes it into the extracellular environment. the role of rhamnolipids in the life cycle and pathogenicity of p. aeruginosa has not been completely understood, but they are known to affect outer membrane composition, cell motility, and biofilm formation. this report is focused on the influence of the outer membrane-bound esterase esta of p. aeruginosa pao1 on rhamnolipid production. esta is an autotransporter protein which e ... | 2007 | 17631636 |
| how rhizobial symbionts invade plants: the sinorhizobium-medicago model. | nitrogen-fixing rhizobial bacteria and leguminous plants have evolved complex signal exchange mechanisms that allow a specific bacterial species to induce its host plant to form invasion structures through which the bacteria can enter the plant root. once the bacteria have been endocytosed within a host-membrane-bound compartment by root cells, the bacteria differentiate into a new form that can convert atmospheric nitrogen into ammonia. bacterial differentiation and nitrogen fixation are depend ... | 2007 | 17632573 |
| modification of small rnas associated with suppression of rna silencing by tobamovirus replicase protein. | plant viruses act as triggers and targets of rna silencing and have evolved proteins to suppress this plant defense response during infection. although tobacco mosaic tobamovirus (tmv) triggers the production of virus-specific small interfering rnas (sirnas), this does not lead to efficient silencing of tmv nor is a tmv-green fluorescent protein (gfp) hybrid able to induce silencing of a gfp-transgene in nicotiana benthamiana, indicating that a tmv silencing suppressor is active and acts downstr ... | 2007 | 17634237 |
| a bacterial e3 ubiquitin ligase targets a host protein kinase to disrupt plant immunity. | many bacterial pathogens of plants and animals use a type iii secretion system to deliver diverse virulence-associated 'effector' proteins into the host cell. the mechanisms by which these effectors act are mostly unknown; however, they often promote disease by suppressing host immunity. one type iii effector, avrptob, expressed by the plant pathogen pseudomonas syringae pv. tomato, has a carboxy-terminal domain that is an e3 ubiquitin ligase. deletion of this domain allows an amino-terminal reg ... | 2007 | 17637671 |
| efficient and rapid agrobacterium-mediated genetic transformation of durum wheat (triticum turgidum l. var. durum) using additional virulence genes. | genetic transformation of wheat, using biolistics or agrobacterium, underpins a range of specific research methods for identifying genes and studying their function in planta. transgenic approaches to study and modify traits in durum wheat have lagged behind those for bread wheat. here we report the use of agrobacterium strain agl1, with additional vir genes housed in a helper plasmid, to transform and regenerate the durum wheat variety ofanto. the use of the basic psoup helper plasmid with no a ... | 2008 | 17638109 |
| x-ray structure of imidazolonepropionase from agrobacterium tumefaciens at 1.87 a resolution. | | 2007 | 17640072 |
| crystal structure of the chromophore binding domain of an unusual bacteriophytochrome, rpbphp3, reveals residues that modulate photoconversion. | bacteriophytochromes rpbphp2 and rpbphp3 from the photosynthetic bacterium rhodopseudomonas palustris work in tandem to modulate synthesis of the light-harvesting complex lh4 in response to light. although rpbphp2 and rpbphp3 share the same domain structure with 52% sequence identity, they demonstrate distinct photoconversion behaviors. rpbphp2 exhibits the "classical" phytochrome behavior of reversible photoconversion between red (pr) and far-red (pfr) light-absorbing states, whereas rpbphp3 ex ... | 2007 | 17640891 |
| enzymatic properties and subcellular localization of arabidopsis beta-n-acetylhexosaminidases. | plant glycoproteins contain substantial amounts of paucimannosidic n-glycans lacking terminal glcnac residues at their nonreducing ends. it has been proposed that this is due to the action of beta-hexosaminidases during late stages of n-glycan processing or in the course of n-glycan turnover. we have now cloned the three putative beta-hexosaminidase sequences present in the arabidopsis (arabidopsis thaliana) genome. when heterologously expressed as soluble forms in spodoptera frugiperda cells, t ... | 2007 | 17644627 |
| molecular interactions of a soluble gibberellin receptor, gid1, with a rice della protein, slr1, and gibberellin. | gibberellin insensitive dwarf1 (gid1) encodes a soluble gibberellin (ga) receptor that shares sequence similarity with a hormone-sensitive lipase (hsl). previously, a yeast two-hybrid (y2h) assay revealed that the gid1-ga complex directly interacts with slender rice1 (slr1), a della repressor protein in ga signaling. here, we demonstrated, by pull-down and bimolecular fluorescence complementation (bifc) experiments, that the ga-dependent gid1-slr1 interaction also occurs in planta. ga(4) was fou ... | 2007 | 17644730 |
| [attempting to enhance the efficiency of t-dna insertional mutant application in rice]. | t-dna tagging method is a high throughput system for identifying and cloning novel genes from t-dna-inserted mutant population created via genetic transformation by agrobacterium tumefaciens. however, the efficiency of using t-dna-inserted mutant population to clone genes in rice was much lower than in arabidopsis. in this study, a rice tagged line with two copies of t-dna segments inserted independently to each other was screened out via a series of verification tests, including the co-segregat ... | 2007 | 17646151 |
| stress-inducible expression of at dreb1a in transgenic peanut (arachis hypogaea l.) increases transpiration efficiency under water-limiting conditions. | water deficit is the major abiotic constraint affecting crop productivity in peanut (arachis hypogaea l.). water use efficiency under drought conditions is thought to be one of the most promising traits to improve and stabilize crop yields under intermittent water deficit. a transcription factor dreb1a from arabidopsis thaliana, driven by the stress inducible promoter from the rd29a gene, was introduced in a drought-sensitive peanut cultivar jl 24 through agrobacterium tumefaciens-mediated gene ... | 2007 | 17653723 |
| the pseudomonas putida lon protease is involved in n-acyl homoserine lactone quorum sensing regulation. | in pseudomonas putida and pseduomonas aeruginosa, the similar ppur/rsal/ppui and lasr/rsal/lasi acyl homoserine lactones (ahls) quorum sensing (qs) systems have been shown to be under considerable regulation by other global regulators. a major regulator is the rsal protein which strongly directly represses the transcription of the p. putida ppui and p. aeruginosa lasi ahl synthases. in this study we screened a transposon mutant bank of p. putida in order to identify if any other regulators were ... | 2007 | 17655747 |
| isolation and antifungal activity of lignans from myristica fragrans against various plant pathogenic fungi. | in a search for plant extracts with potent in vivo antifungal activity against various plant diseases, we found that treatment with a methanol extract of myristica fragrans houttyn (nutmeg) seeds reduced the development of various plant diseases. the objectives of the present study were to isolate and determine antifungal substances from my. fragrans and to evaluate their antifungal activities. | 2007 | 17659535 |
| 4-sulfomuconolactone hydrolases from hydrogenophaga intermedia s1 and agrobacterium radiobacter s2. | the 4-carboxymethylen-4-sulfo-but-2-en-olide (4-sulfomuconolactone) hydrolases from hydrogenophaga intermedia strain s1 and agrobacterium radiobacter strain s2 are part of a modified protocatechuate pathway responsible for the degradation of 4-sulfocatechol. in both strains, the hydrolase-encoding genes occur downstream of those encoding the enzymes that catalyze the lactonization of 3-sulfomuconate. the deduced amino acid sequences of the 4-sulfomuconolactone hydrolases demonstrated the highest ... | 2007 | 17660282 |
| salicylic acid, yersiniabactin, and pyoverdin production by the model phytopathogen pseudomonas syringae pv. tomato dc3000: synthesis, regulation, and impact on tomato and arabidopsis host plants. | a genetically tractable model plant pathosystem, pseudomonas syringae pv. tomato dc3000 on tomato and arabidopsis thaliana hosts, was used to investigate the role of salicylic acid (sa) and iron acquisition via siderophores in bacterial virulence. pathogen-induced sa accumulation mediates defense in these plants, and dc3000 contains the genes required for the synthesis of sa, the sa-incorporated siderophore yersiniabactin (ybt), and the fluorescent siderophore pyoverdin (pvd). we found that dc30 ... | 2007 | 17660289 |
| a sepal-expressed adp-glucose pyrophosphorylase gene (ntagp) is required for petal expansion growth in 'xanthi' tobacco. | in this study, a tobacco (nicotiana tabacum 'xanthi') adp-glucose pyrophosphorylase cdna (ntagp) was isolated from a flower bud cdna library and the role of ntagp in the growth of the floral organ was characterized. the expression of ntagp was high in the sepal, moderate in the carpel and stamen, and low in the petal tissues. ntagp-antisense plants produced flowers with abnormal petal limbs due to the early termination of the expansion growth of the petal limbs between the corolla lobes. microsc ... | 2007 | 17660352 |
| identification of pti-sakura dna region conferring enhancement of plasmid incompatibility and stability. | in agrobacterium tumefaciens, the stability of ti plasmids differs depending on the strain. so far, little is known about genes that cause the difference in stability. the repabc operon is responsible for replication and incompatibility of ti plasmids. we constructed recombinant plasmids carrying the repabc operon and different portions of pti-sakura. cells having the recombinant plasmids that harbored a 2.6-kbp nhei fragment of pti-sakura were found to be transformed via conjugation 100-fold le ... | 2007 | 17660690 |
| cadophora finlandia and phialocephala fortinii: agrobacterium-mediated transformation and functional gfp expression. | hygromycin b resistance was transferred to the sterile mycelia of cadophora finlandia and phialocephala fortinii by co-cultivation with agrobacterium tumefaciens. constitutively expressed green fluorescent protein (gfp) was also introduced using the same vector. confocal laser scanning microscopy (clsm) revealed strong fluorescence of transformants. both traits were mitotically stable during one year of subculturing on non-selective growth medium. southern blot analysis showed that the majority ... | 2007 | 17662587 |
| alternative methods for genetic transformation of pseudozyma antarctica, a basidiomycetous yeast-like fungus. | electroporation and agrobacterium tumefaciens-mediated transformation (atmt) were adapted and optimized for genetic transformation of the basidiomycetous yeast-like fungus pseudozyma antarctica as alternatives to the cumbersome peg/cacl(2)-mediated transformation of protoplasts. electroporation yielded 100-200 transformants per mug of dna per 10(8) cells after 3 days on selective medium. for its part, atmt yielded 60-160 transformants per 10(6) input cfu after 5-10 days on a selective medium. tr ... | 2007 | 17669528 |
| high-frequency reversion of geminivirus replication protein mutants during infection. | the geminivirus replication protein al1 interacts with retinoblastoma-related protein (rbr), a key regulator of the plant division cell cycle, to induce conditions permissive for viral dna replication. previous studies of tomato golden mosaic virus (tgmv) al1 showed that amino acid l148 in the conserved helix 4 motif is critical for rbr binding. in this work, we examined the effect of an l148v mutation on tgmv replication in tobacco cells and during infection of nicotiana benthamiana plants. the ... | 2007 | 17670823 |
| modification of substrate specificity in single point mutants of agrobacterium tumefaciens type ii nadh dehydrogenase. | type ii nadh dehydrogenases (ndh-2) are monomeric flavoenzymes catalyzing electron transfer from nadh to quinones. while most ndh-2 preferentially oxidize nadh, some of these enzymes have been reported to efficiently oxidize nadph. with the aim to modify the nadph vs nadh specificity of the relatively nadh specific agrobacterium tumefaciens ndh-2, two conserved residues (e and a) of the substrate binding domain were, respectively, mutated to q and s. we show that when e was replaced by q at posi ... | 2007 | 17673203 |
| [efficient agrobacterium-mediated transformation of soybean]. | to improve agrobacterium tumefaciens mediated transformation of embryonic tips of soybean [glycine max (l.) merr], the effect of several factors on transformation efficiency were examined by measuring transient expression levels of beta-glucuronidase and the number of resistant explants. the hypervirulent agrobacterium tumefaciens strain kyrt1 was proved to be a better transformer than eha105 and lba4404. improved transformation efficiencies were obtained when embryonic tips were incubated with ... | 2007 | 17674770 |
| adaptive evolution has targeted the c-terminal domain of the rxlr effectors of plant pathogenic oomycetes. | oomycete plant pathogens deliver effector proteins inside host cells to modulate plant defense circuitry and to enable parasitic colonization. these effectors are defined by a conserved motif, termed rxlr (for arg, any amino acid, leu, arg), that is located downstream of the signal peptide and that has been implicated in host translocation. because the phenotypes of rxlr effectors extend to plant cells, their genes are expected to be the direct target of the evolutionary forces that drive the an ... | 2007 | 17675403 |
| cell-type specificity of the expression of os bor1, a rice efflux boron transporter gene, is regulated in response to boron availability for efficient boron uptake and xylem loading. | we describe a boron (b) transporter, os bor1, in rice (oryza sativa). os bor1 is a plasma membrane-localized efflux transporter of b and is required for normal growth of rice plants under conditions of limited b supply (referred to as -b). disruption of os bor1 reduced b uptake and xylem loading of b. the accumulation of os bor1 transcripts was higher in roots than that in shoots and was not affected by b deprivation; however, os bor1 was detected in the roots of wild-type plants under -b condit ... | 2007 | 17675406 |
| biofilm interactions between distinct bacterial genera isolated from drinking water. | in the environment, multiple microorganisms coexist as communities, competing for resources and often associated as biofilms. in this study, single- and dual-species biofilm formation by, and specific activities of, six heterotrophic intergeneric bacteria were determined using 96-well polystyrene plates over a 72-h period. these bacteria were isolated from drinking water and identified by partial 16s rrna gene sequencing. a series of planktonic studies was also performed, assessing the bacterial ... | 2007 | 17675433 |
| cloning and transfer of the salmonella pathogenicity island 2 type iii secretion system for studies of a range of gram-negative genera. | the engineering of bacterial strains with specific phenotypes frequently requires the use of blocks or "cassettes" of genes that act together to perform a desired function. the potential benefits of utilizing type iii secretion systems in this regard are becoming increasingly realized since these systems can be used to direct interactions with host cells for beneficial purposes such as vaccine development, anticancer therapies, and targeted protein delivery. however, convenient methods to clone ... | 2007 | 17675443 |
| rasta-bacteria: a web-based tool for identifying toxin-antitoxin loci in prokaryotes. | toxin/antitoxin (ta) systems, viewed as essential regulators of growth arrest and programmed cell death, are widespread among prokaryotes, but remain sparsely annotated. we present rasta-bacteria, an automated method allowing quick and reliable identification of ta loci in sequenced prokaryotic genomes, whether they are annotated open reading frames or not. the tool successfully confirmed all reported ta systems, and spotted new putative loci upon screening of sequenced genomes. rasta-bacteria i ... | 2007 | 17678530 |
| [expression of tmv coat protein gene rnai in transgenic tobacco plants confer immunity to tobacco mosaic virus infection]. | rnai technique has been proved as a powerful tool for plant breeding. in this paper, the coat protein of tobacco mosaic virus (tmv) was used for constructing the rnai interference vector. the tobacco varieties k326 and longjiang 911 were transformed via agrobacterium tumefaciens-mediated transformation, and transgenic plants were generated. the expression analysis with real-time pcr indicated that tmv rna had been degraded varied in different transgenic lines. field assay revealed that 83% and 9 ... | 2007 | 17681934 |
| homologous cpn60 genes in rhizobium leguminosarum are not functionally equivalent. | many bacteria possess 2 or more genes for the chaperonin groel and the cochaperonin groes. in particular, rhizobial species often have multiple groel and groes genes, with a high degree of amino-acid similarity, in their genomes. the rhizobium leguminosarum strain a34 has 3 complete groe operons, which we have named cpn.1, cpn.2 and cpn.3. previously we have shown the cpn. 1 operon to be essential for growth, but the two other cpn operons to be dispensable. here, we have investigated the extent ... | 2007 | 17688191 |
| the organization of high-affinity ammonium uptake in arabidopsis roots depends on the spatial arrangement and biochemical properties of amt1-type transporters. | the ammonium transporter (amt) family comprises six isoforms in arabidopsis thaliana. here, we describe the complete functional organization of root-expressed amts for high-affinity ammonium uptake. high-affinity influx of (15)n-labeled ammonium in two transposon-tagged amt1;2 lines was reduced by 18 to 26% compared with wild-type plants. enrichment of the amt1;2 protein in the plasma membrane and localization of amt1;2 promoter activity in the endodermis and root cortex indicated that amt1;2 me ... | 2007 | 17693533 |
| signaling from an altered cell wall to the nucleus mediates sugar-responsive growth and development in arabidopsis thaliana. | sugars such as glucose function as signal molecules that regulate gene expression, growth, and development in plants, animals, and yeast. to understand the molecular mechanisms of sugar responses, we isolated and characterized an arabidopsis thaliana mutant, high sugar response8 (hsr8), which enhances sugar-responsive growth and gene expression. light-grown hsr8 plants exhibited increased starch and anthocyanin and reduced chlorophyll content in response to glucose treatment. dark-grown hsr8 see ... | 2007 | 17693536 |
| biosynthesis and immunogenicity of glucosylceramide in cryptococcus neoformans and other human pathogens. | | 2007 | 17693597 |
| assessing the expression of chicken anemia virus proteins in plants. | chicken anemia virus (cav) is an important pathogen of chicken worldwide, causing severe anemia and immunodeficiency. its small single-stranded dna genome (2.3kb) encodes three proteins: vp1, the only structural protein, vp2, a protein phosphatase, and vp3, also known as apoptin, which induces apoptosis. in this study, cav proteins were expressed in plants as an alternative for recombinant protein production in animal cells. additionally, the effect of vp3 expression was tested to evaluate possi ... | 2007 | 17698236 |
| complete nucleotide sequence of the pctx-m3 plasmid and its involvement in spread of the extended-spectrum beta-lactamase gene blactx-m-3. | here we report the nucleotide sequence of pctx-m3, a highly conjugative plasmid that is responsible for the extensive spread of the gene coding for the ctx-m-3 extended-spectrum beta-lactamase in clinical populations of the family enterobacteriaceae in poland. the plasmid belongs to the incl/m incompatibility group, is 89,468 bp in size, and carries 103 putative genes. besides bla(ctx-m-3), it also bears the bla(tem-1), aacc2, and arma genes, as well as integronic aada2, dfra12, and sul1, which ... | 2007 | 17698626 |
| functions of osbzr1 and 14-3-3 proteins in brassinosteroid signaling in rice. | brassinosteroids (br) are essential growth hormones found throughout the plant kingdom. br bind to the receptor kinase bri1 on the cell surface to activate a signal transduction pathway that regulates nuclear gene expression and plant growth. to understand the downstream br signaling mechanism in rice, we studied the function of osbzr1 using reverse genetic approaches and identified osbzr1-interacting proteins. suppressing osbzr1 expression by rnai resulted in dwarfism, erect leaves, reduced br ... | 2007 | 17699623 |
| live cell imaging of repetitive dna sequences via gfp-tagged polydactyl zinc finger proteins. | several techniques are available to study chromosomes or chromosomal domains in nuclei of chemically fixed or living cells. current methods to detect dna sequences in vivo are limited to trans interactions between a dna sequence and a transcription factor from natural systems. here, we expand live cell imaging tools using a novel approach based on zinc finger-dna recognition codes. we constructed several polydactyl zinc finger (pzf) dna-binding domains aimed to recognize specific dna sequences i ... | 2007 | 17704126 |
| a wd40 domain cyclophilin interacts with histone h3 and functions in gene repression and organogenesis in arabidopsis. | chromatin-based silencing provides a crucial mechanism for the regulation of gene expression. we have identified a wd40 domain cyclophilin, cyclophilin71 (cyp71), which functions in gene repression and organogenesis in arabidopsis thaliana. disruption of cyp71 resulted in ectopic activation of homeotic genes that regulate meristem development. the cyp71 mutant plants displayed dramatic defects, including reduced apical meristem activity, delayed and abnormal lateral organ formation, and arrested ... | 2007 | 17704213 |
| dual regulation role of gh3.5 in salicylic acid and auxin signaling during arabidopsis-pseudomonas syringae interaction. | salicylic acid (sa) plays a central role in plant disease resistance, and emerging evidence indicates that auxin, an essential plant hormone in regulating plant growth and development, is involved in plant disease susceptibility. gh3.5, a member of the gh3 family of early auxin-responsive genes in arabidopsis (arabidopsis thaliana), encodes a protein possessing in vitro adenylation activity on both indole-3-acetic acid (iaa) and sa. here, we show that gh3.5 acts as a bifunctional modulator in bo ... | 2007 | 17704230 |
| athipm, an ortholog of the apple hrpn-interacting protein, is a negative regulator of plant growth and mediates the growth-enhancing effect of hrpn in arabidopsis. | hrpn (harpin) protein is critical to the virulence of the fire blight pathogen erwinia amylovora in host plants like apple (malus x domestica). moreover, exogenous treatment of arabidopsis (arabidopsis thaliana), a nonhost plant, with partially purified hrpn enhances growth. to address the bases of the effects of hrpn in disease, we sought a hrpn-interacting protein(s) in apple, using a yeast two-hybrid assay. a single positive clone, designated hipm (hrpn-interacting protein from malus), was fo ... | 2007 | 17704235 |
| capsid protein-mediated recruitment of host dnaj-like proteins is required for potato virus y infection in tobacco plants. | the capsid protein (cp) of potyviruses is required for various steps during plant infection, such as virion assembly, cell-to-cell movement, and long-distance transport. this suggests a series of compatible interactions with putative host factors which, however, are largely unknown. by using the yeast two-hybrid system the cp from potato virus y (pvy) was found to interact with a novel subset of dnaj-like proteins from tobacco, designated ntcpips. mutational analysis identified the cp core regio ... | 2007 | 17715215 |
| the p122 subunit of tobacco mosaic virus replicase is a potent silencing suppressor and compromises both small interfering rna- and microrna-mediated pathways. | one of the functions of rna silencing in plants is to defend against molecular parasites, such as viruses, retrotransposons, and transgenes. plant viruses are inducers, as well as targets, of rna silencing-based antiviral defense. replication intermediates or folded viral rnas activate rna silencing, generating small interfering rnas (sirnas), which are the key players in the antiviral response. viruses are able to counteract rna silencing by expressing silencing-suppressor proteins. it has been ... | 2007 | 17715232 |
| partial protection against brucella infection in mice by immunization with nonpathogenic alphaproteobacteria. | previous findings indicate that brucella antigens and those from nonpathogenic alphaproteobacteria (npap) are cross-recognized by the immune system. we hypothesized that immunization with npap would protect mice from brucella infection. mice were immunized subcutaneously with heat-killed ochrobactrum anthropi, sinorhizobium meliloti, mesorhizobium loti, agrobacterium tumefaciens, or brucella melitensis h38 (standard positive control) before intravenous challenge with brucella abortus 2308. cross ... | 2007 | 17715332 |
| one step engineering of t7-expression strains for protein production: increasing the host-range of the t7-expression system. | the t7-expression system has been very useful for protein expression in escherichia coli. however, it is often desirable to over-express proteins in species other than e. coli. here, we constructed an inducible broad-host-range t7-expression transposon, which allows simple one-step construction of t7-expression strains in various species, providing the option to over-express proteins of interest in a broader host-range. this transposon contains the t7 rna polymerase driven by the lacuv5 promoter ... | 2007 | 17716915 |
| domestication and breeding of tomatoes: what have we gained and what can we gain in the future? | it has been shown that a large variation is present and exploitable from wild solanum species but most of it is still untapped. considering the thousands of solanum accessions in different gene banks and probably even more that are still untouched in the andes, it is a challenge to exploit the diversity of tomato. what have we gained from tomato domestication and breeding and what can we gain in the future? | 2007 | 17717024 |
| trbo: a high-efficiency tobacco mosaic virus rna-based overexpression vector. | transient expression is a rapid, useful approach for producing proteins of interest in plants. tobacco mosaic virus (tmv)-based transient expression vectors can express very high levels of foreign proteins in plants. however, tmv vectors are, in general, not efficiently delivered to plant cells by agroinfection. it was determined that agroinfection was very efficient with a 35s promoter-driven tmv replicon that lacked the tmv coat protein gene sequence. this coat protein deletion vector had seve ... | 2007 | 17720752 |
| reverse genetics of floral scent: application of tobacco rattle virus-based gene silencing in petunia. | floral fragrance is responsible for attracting pollinators as well as repelling pathogens and pests. as such, it is of immense biological importance. molecular dissection of the mechanisms underlying scent production would benefit from the use of model plant systems with big floral organs that generate an array of volatiles and that are amenable to methods of forward and reverse genetics. one candidate is petunia (petunia hybrida), which has emerged as a convenient model system, and both rnai an ... | 2007 | 17720754 |
| tcpa, an ftsk/spoiiie homolog, is essential for transfer of the conjugative plasmid pcw3 in clostridium perfringens. | the conjugative tetracycline resistance plasmid pcw3 is the paradigm conjugative plasmid in the anaerobic gram-positive pathogen clostridium perfringens. two closely related ftsk/spoiiie homologs, tcpa and tcpb, are encoded on pcw3, which is significant since ftsk domains are found in coupling proteins of gram-negative conjugation systems. to develop an understanding of the mechanism of conjugative transfer in c. perfringens, we determined the role of these proteins in the conjugation process. m ... | 2007 | 17720795 |
| inhibition of fungal and bacterial plant pathogens in vitro and in planta with ultrashort cationic lipopeptides. | plant diseases constitute an emerging threat to global food security. many of the currently available antimicrobial agents for agriculture are highly toxic and nonbiodegradable and cause extended environmental pollution. moreover, an increasing number of phytopathogens develop resistance to them. recently, we have reported on a new family of ultrashort antimicrobial lipopeptides which are composed of only four amino acids linked to fatty acids (a. makovitzki, d. avrahami, and y. shai, proc. natl ... | 2007 | 17720828 |
| high-efficiency protein expression in plants from agroinfection-compatible tobacco mosaic virus expression vectors. | plants are increasingly being examined as alternative recombinant protein expression systems. recombinant protein expression levels in plants from tobacco mosaic virus (tmv)-based vectors are much higher than those possible from plant promoters. however the common tmv expression vectors are costly, and at times technically challenging, to work with. therefore it was a goal to develop tmv expression vectors that express high levels of recombinant protein and are easier, more reliable, and more co ... | 2007 | 17723150 |
| a metabolic pathway leading to mannosylfructose biosynthesis in agrobacterium tumefaciens uncovers a family of mannosyltransferases. | a metabolic pathway for biosynthesis of the nonreducing disaccharide mannosylfructose (beta-fructofuranosyl-alpha-mannopyranoside), an important osmolyte in agrobacterium tumefaciens, was discovered. we have identified and functionally characterized two orfs that correspond to genes (named mfpsa and mfppa) encoding the rare enzymes mannosylfructose-phosphate synthase and mannosylfructose-phosphate phosphatase, an associated phosphohydrolase. the mfpsa and mfppa genes are arranged in an operon st ... | 2007 | 17728402 |
| conjugative transfer by the virulence system of agrobacterium tumefaciens. | agrobacterium tumefaciens transfers part of its ti plasmid, the transferred dna (t-dna), to plant cells during tumor induction. expression of this t-dna in plant cells results in their transformation into tumor cells. there are similarities between the process of t-dna transfer to plants and the process of bacterial conjugation. here, the t-dna transfer machinery mediated conjugation between bacteria. thus, products of the vir region of the ti plasmid of agrobacterium tumefaciens, normally invol ... | 1992 | 17736763 |
| introduction of genetic material into plant cells. | the tumor-inducing (ti) plasmid of the soil microorganism agrobacterium tumefaciens is the agent of crown gall disease in dicotyledonous plants. the ti plasmid contains two regions that are essential for the production of transformed cells. one of these regions, termed transfer dna, induces tumor formation and is found in all established plant tumor lines; the other, termed the virulence region, is essential for the formation but not the maintenance of tumors. transfer dna, which transfers to th ... | 1983 | 17738341 |
| tumor production by hormones from phytomonas tumefaciens. | | 1937 | 17743013 |
| a simple and general method for transferring genes into plants. | transformed petunia, tobacco, and tomato plants have been produced by means of a novel leaf disk transformation-regeneration method. surface-sterilized leaf disks were inoculated with an agrobacterium tumefaciens strain containing a modified tumor-inducing plasmid (in which the phytohormone biosynthetic genes from transferred dna had been deleted and replaced with a chimeric gene for kanamycin resistance) and cultured for 2 days. the leaf disks were then transferred to selective medium containin ... | 1985 | 17757866 |
| transient and stable expression of the firefly luciferase gene in plant cells and transgenic plants. | the luciferase gene from the firefly, photinus pyralis, was used as a reporter of gene expression by light production in transfected plant cells and transgenic plants. a complementary dna clone of the firefly luciferase gene under the control of a plant virus promoter (cauliflower mosaic virus 35s rna promoter) was introduced into plant protoplast cells (daucus carota) by electroporation and into plants (nicotiana tabacum) by use of the agrobacterium tumefaciens tumor-inducing plasmid. extracts ... | 1986 | 17758108 |
| site-specific nick in the t-dna border sequence as a result of agrobacterium vir gene expression. | the t-dna transfer process of agrobacterium tumefaciens is activated by the induction of the expression of the ti plasmid virulence (vir) loci by plant signal molecules such as acetosyringone. the vir gene products act in trans to mobilize the t-dna element from the bacterial ti plasmid. the t-dna is bounded by 25-base pair direct repeat sequences, which are the only sequences on the element essential for transfer. thus, specific reactions must occur at the border sites to generate a transferabl ... | 1987 | 17758248 |
| the n-terminal region of pseudomonas type iii effector avrptob elicits pto-dependent immunity and has two distinct virulence determinants. | resistance to bacterial speck disease in tomato is activated by the physical interaction of the host pto kinase with either of the sequence-dissimilar type iii effector proteins avrpto or avrptob (hopab2) from pseudomonas syringae pv. tomato. pto-mediated immunity requires prf, a protein with a nucleotide-binding site and leucine-rich repeats. the n-terminal 307 amino acids of avrptob were previously reported to interact with the pto kinase, and we show here that this region (avrptob(1-307)) is ... | 2007 | 17764515 |
| the hemibiotrophic lifestyle of colletotrichum species. | colletotrichum species infect several economically important crop plants. to establish a compatible parasitic interaction, a specialized infection cell, the melanized appressorium, is differentiated on the cuticle of the host. after penetration, an infection vesicle and primary hyphae are formed. these structures do not kill the host cell and show some similarities with haustoria formed by powdery mildews and rust fungi. therefore, this stage of infection is called biotrophic. later in the infec ... | 2008 | 17765357 |
| psat rna interference vectors: a modular series for multiple gene down-regulation in plants. | rna interference (rnai) is a powerful tool for functional gene analysis, which has been successfully used to down-regulate the levels of specific target genes, enabling loss-of-function studies in living cells. hairpin (hp) rna expression cassettes are typically constructed on binary plasmids and delivered into plant cells by agrobacterium-mediated genetic transformation. realizing the importance of rnai for basic plant research, various vectors have been developed for rnai-mediated gene silenci ... | 2007 | 17766396 |
| arabidopsis transparent testa glabra2 is directly regulated by r2r3 myb transcription factors and is involved in regulation of glabra2 transcription in epidermal differentiation. | arabidopsis thaliana transparent testa glabra2 (ttg2) encodes a wrky transcription factor and is expressed in young leaves, trichomes, seed coats, and root hairless cells. an examination of several trichome and root hair mutants indicates that myb and bhlh genes regulate ttg2 expression. two myb binding sites in the ttg2 5' regulatory region act as cis regulatory elements and as direct targets of r2r3 myb transcription factors such as werewolf, glabra1, and transparent testa2. mutations in ttg2 ... | 2007 | 17766401 |
| the snrk1a protein kinase plays a key role in sugar signaling during germination and seedling growth of rice. | sugars repress alpha-amylase expression in germinating embryos and cell cultures of rice (oryza sativa) through a sugar response complex (src) in alpha-amylase gene promoters and its interacting transcription factor mybs1. the snf1 protein kinase is required for the derepression of glucose-repressible genes in yeast. in this study, we explored the role of the yeast snf1 ortholog in rice, snrk1, in sugar signaling and plant growth. rice embryo transient expression assays indicated that snrk1a and ... | 2007 | 17766403 |
| motility and chemotaxis in agrobacterium tumefaciens surface attachment and biofilm formation. | bacterial motility mechanisms, including swimming, swarming, and twitching, are known to have important roles in biofilm formation, including colonization and the subsequent expansion into mature structured surface communities. directed motility requires chemotaxis functions that are conserved among many bacterial species. the biofilm-forming plant pathogen agrobacterium tumefaciens drives swimming motility by utilizing a small group of flagella localized to a single pole or the subpolar region ... | 2007 | 17766409 |
| identification of novel surface proteins of anaplasma phagocytophilum by affinity purification and proteomics. | anaplasma phagocytophilum is the etiologic agent of human granulocytic anaplasmosis (hga), one of the major tick-borne zoonoses in the united states. the surface of a. phagocytophilum plays a crucial role in subverting the hostile host cell environment. however, except for the p44/msp2 outer membrane protein family, the surface components of a. phagocytophilum are largely unknown. to identify the major surface proteins of a. phagocytophilum, a membrane-impermeable, cleavable biotin reagent, sulf ... | 2007 | 17766422 |
| gene transfer in cereals. | until recently, gene transfer in plants was achieved only by sexual hybridization. now, in addition, plant genetic manipulation, with the use of both recombinant dna and protoplast fusion technology, is being applied to an increasing range of plants. the soil bacterium agrobacterium tumefaciens, with its associated plasmid, is used as a vector for introducing dna into the genomes of dicotyledonous plants, but it has not proved suitable for cereals. instead, the direct uptake of plasmid dna into ... | 1987 | 17770329 |
| inheritance of functional foreign genes in plants. | morphologically normal plants were regenerated from nicotiana plumbaginifolia cells transformed with an agrobacterium tumefaciens strain containing a tumor-inducing plasmid with a chimeric gene for kanamycin resistance. the presence of the chimeric gene in regenerated plants was demonstrated by southern hybridization analysis, and its expression in plant tissues was confirmed by the ability of leaf segments to form callus on media containing kanamycin at concentrations that were normally inhibit ... | 1984 | 17781445 |
| morphological changes in bacterium tumefaciens. | | 1925 | 17783906 |
| single-stranded dna binding protein encoded by the vire locus of agrobacterium tumefaciens. | the transfer process of t (transfer)-dna of agrobacterium tumefaciens is activated after the induction of the expression of the ti plasmid virulence (vir) loci by plant signal molecules such as acetosyringone. the vir gene products then act to generate a free transferable single-stranded copy of the t-dna, designated the t-strand. although some vir proteins are responsible for the synthesis of the t-strand, others may mediate t-strand transfer to plant cells as part of a dna-protein complex. her ... | 1988 | 17784072 |
| alleviating peanut allergy using genetic engineering: the silencing of the immunodominant allergen ara h 2 leads to its significant reduction and a decrease in peanut allergenicity. | peanut allergy is one of the most life-threatening food allergies and one of the serious challenges facing the peanut and food industries. current proposed solutions focus primarily on ways to alter the immune system of patients allergic to peanut. however, with the advent of genetic engineering novel strategies can be proposed to solve the problem of peanut allergy from the source. the objectives of this study were to eliminate the immunodominant ara h 2 protein from transgenic peanut using rna ... | 2008 | 17784907 |
| genomic analysis reveals the major driving forces of bacterial life in the rhizosphere. | mutualistic interactions less well known than those between rhizobia and legumes are commonly found between plants and bacteria, frequently pseudomonads, which colonize roots and adjacent soil areas (the rhizosphere). | 2007 | 17784941 |