Publications

TitleAbstractYear(sorted ascending)
Filter
PMID
Filter
bioavailability of adsorbed phenanthrene by black carbon and multi-walled carbon nanotubes to agrobacterium.carbonaceous sorbents including black carbon (bc) and carbon nanotubes have attracted research attention around the world because of their effects on bioavailability of hydrophobic organic compounds (hocs) in sediments and soils. in this research, (14)c-labeled and unlabeled phenanthrene were spiked into three artificial sediments: (i) a sediment sample without amorphous organic carbon (oc) and with bc collected from the yangtze river (bc-yr), (ii) a sediment without oc and with multi-walled car ...201020116085
how inefficient rhizobia prolong their existence within nodules.legumes are important food sources and therefore, the nitrogen fixing ability of legume-rhizobia symbioses have great potential to improve crop yields and/or reduce the use of nitrogenous fertilisers. unfortunately the nitrogen fixing efficiency of many legume-rhizobial combinations is low. what restricts nodule efficiency? we believe that one answer lies in the neglected field of signal exchange within mature nodules. indeed molecular determinants that permit rhizobia to persist for months with ...201020117958
computational prediction of type iii secreted proteins from gram-negative bacteria.type iii secretion system (t3ss) is a specialized protein delivery system in gram-negative bacteria that injects proteins (called effectors) directly into the eukaryotic host cytosol and facilitates bacterial infection. for many plant and animal pathogens, t3ss is indispensable for disease development. recently, t3ss has also been found in rhizobia and plays a crucial role in the nodulation process. although a great deal of efforts have been done to understand type iii secretion, the precise mec ...201020122221
agrobacterium radiobacter bacteremia in a child with acute lymphoblastic leukemia.agrobacteria are gram-negative tumorigenic plant pathogens that rarely cause infections in humans.201020127221
bnyvv-derived dsrna confers resistance to rhizomania disease of sugar beet as evidenced by a novel transgenic hairy root approach.agrobacterium rhizogenes-transformed sugar beet hairy roots, expressing dsrna from the beet necrotic yellow vein virus replicase gene, were used as a novel approach to assess the efficacy of three intron-hairpin constructs at conferring resistance to rhizomania disease. genetically engineered roots were similar in morphology to wild type roots but were characterized by a profound abundancy, rapid growth rate and, in some cases, plagiotropic development. upon challenge inoculation, seedlings show ...201020127510
effects of initial inoculation density of paenibacillus polymyxa on colony formation and starch-hydrolytic activity in relation to root rot in ginseng.to examine the relationships between population growth and biological characters of the plant-growth-promoting rhizobacterium paenibacillus polymyxa gbr-1.201020132376
ligands of boron in pisum sativum nodules are involved in regulation of oxygen concentration and rhizobial infection.boron (b) is an essential nutrient for n(2)-fixing legume-rhizobia symbioses, and the capacity of borate ions to bind and stabilize biomolecules is the basis of any b function. we used a borate-binding-specific resin and immunostaining techniques to identify b ligands important for the development of pisum sativum-rhizobium leguminosarum 3841 symbiotic nodules. arabinogalactan-extensin (agpe), recognized by mac 265 antibody, appeared heavily bound to the resin in extracts derived from b-sufficie ...201020132519
agrobacterium type iv secretion system and its substrates form helical arrays around the circumference of virulence-induced cells.the genetic transformation of plant cells by agrobacterium tumefaciens results from the transfer of dna and proteins via a specific virulence (vir) -induced type iv secretion system (t4ss). to better understand t4ss function, we analyzed the localization of its structural components and substrates by deconvolution fluorescence microscopy. gfp fusions to t4ss proteins with cytoplasmic tails, virb8 and vird4, or cytoplasmic t4ss substrate proteins, vird2, vire2, and virf, localize in a helical pat ...201020133577
a remorin protein interacts with symbiotic receptors and regulates bacterial infection.remorin proteins have been hypothesized to play important roles during cellular signal transduction processes. induction of some members of this multigene family has been reported during biotic interactions. however, no roles during host-bacteria interactions have been assigned to remorin proteins until now. we used root nodule symbiosis between medicago truncatula and sinorhizobium meliloti to study the roles of a remorin that is specifically induced during nodulation. here we show that this ol ...201020133878
effects of transgenic rootstocks on growth and development of non-transgenic scion cultivars in apple.although cultivation of genetic modified (gm) annual crops has been steadily increasing in the recent 10 years, the commercial cultivation of gm fruit tree is still very limited and reports of field trials on gm fruit trees are rare. this is probably because development and evaluation of gm fruit trees require a long period of time due to long life cycles of trees. in this study, we report results from a field trial on three rolb transgenic dwarfing apple rootstocks of m26 and m9 together with n ...201020135223
boron deficiency results in induction of pathogenesis-related proteins from the pr-10 family during the legume-rhizobia interaction.boron (b) deficiency has a strong effect on molecular and cellular plant-bacteria interactions during the development of the legume-rhizobia symbiosis, leading to reduced infection and early necrosis of nodules, resembling a pathogenic-like rather than a symbiotic interaction. therefore, induction of pathogenesis-related (prs) proteins was investigated here in legume root nodules. following two-dimensional electrophoresis and maldi-tof spectrometry analysis of proteins extracted from pisum sativ ...201020138685
transgenic leucaena leucocephala expressing the rhizobium gene pyda encoding a meta-cleavage dioxygenase shows reduced mimosine content.the use of the tree-legume leucaena leucocephala (leucaena), which contains high levels of proteins in its foliage, is limited due to the presence of the toxic free amino acid mimosine. the goal of this research was to develop transgenic leucaena with reduced mimosine content. two genes, pyda and pydb, encoding a meta-cleavage dioxygenase (ec 1.13.11.2) and a pyruvate hydrolase (ec 3.7.1.6), respectively, from the mimosine-degrading leucaena symbiont rhizobium sp. strain tal1145, were used to tr ...201020138776
salicylic acid differentially affects suspension cell cultures of lotus japonicus and one of its non-symbiotic mutants.salicylic acid (sa) is known to play an important role in the interaction between plant and micro-organisms, both symbiotic and pathogen. in particular, high levels of sa block nodule formation and mycorrhizal colonization in plants. a mutant of lotus japonicus, named ljsym4-2, was characterized as unable to establish positive interactions with rhizobium and fungi (nod(-), myc(-)); in particular, it does not recognize signal molecules released by symbiotic micro-organisms so that eventually, epi ...201020012170
current state of coenzyme q(10) production and its applications.coenzyme q(10) (coq(10)), an obligatory cofactor in the aerobic respiratory electron transfer for energy generation, is formed from the conjugation of a benzoquinone ring with a hydrophobic isoprenoid chain. coq(10) is now used as a nutritional supplement because of its antioxidant properties and is beneficial in the treatment of several human diseases when administered orally. bioprocesses have been developed for the commercial production of coq(10) because of its increased demand, and these bi ...201020012276
agrobacterium tumefaciens-mediated transformation of withania somnifera (l.) dunal: an important medicinal plant.this report describes agrobacterium tumefaciens-mediated transformation of withania somnifera--an important indian medicinal plant. a. tumefaciens strain lba4404, containing the binary vector pig121hm was used for transformation, along with the gusa reporter gene with intron under the transcriptional control of the cauliflower mosaic virus (camv) 35s promoter. the leaf segments from two-and-a-half-month-old green house-grown seedlings were more efficient in transformation, as compared to those f ...201020012541
rapid in planta evaluation of root expressed transgenes in chimeric soybean plants.production of stable transgenic plants is one factor that limits rapid evaluation of tissue specific transgene expression. to hasten the assessment of transgenes in planta, we evaluated the use of chimeric soybean seedlings expressing transgenic products in roots. tap roots from four-day old seedlings (cultivars 'jack' and ks4704) were excised and hairy roots were induced from hypocotyls via agrobacterium rhizogenes-mediated transformation. inoculated hypocotyls were screened on a ms-based mediu ...201020012965
the nodc, nodg, and glgx genes of rhizobium tropici strain prf 81.rhizobium tropici is a diazotrophic microsymbiont of common bean (phaseolus vulgaris l.) that encompasses important but still poorly studied tropical strains, and a recent significant contribution to the knowledge of the species was the publication of a genomic draft of strain prf 81, which revealed several novel genes [pinto et al. funct int gen 9:263-270, 2009]. in this study, we investigated the transcription of nodc, nodg, and glgx genes, located in the nod operon of prf 81 strain, by revers ...201020013017
an efficient system to detect protein ubiquitination by agroinfiltration in nicotiana benthamiana.the ubiquitination proteasome pathway has been demonstrated to regulate all plant developmental and signaling processes. e3 ligase/substrate-specific interactions and ubiquitination play important roles in this pathway. however, due to technical limitations only a few instances of e3 ligase-substrate binding and protein ubiquitination in plants have been directly evidenced. an efficient in vivo and in vitro ubiquitination assay was developed for analysis of protein ubiquitination reactions by ag ...201020015064
molecular identification of airborne bacteria associated with aerial spraying of bovine slurry waste employing 16s rrna gene pcr and gene sequencing techniques.polymerase chain reaction amplification of the universal 16s ribosomal rna (rrna) gene was performed on a collection of 38 bacterial isolates, originating from air sampled immediately adjacent to the agricultural spreading of bovine slurry. a total of 16 bacterial genera were identified including both gram-positive and gram-negative genera. gram-positive organisms accounted for 34/38 (89.5%) of total bacterial numbers consisting of 12 genera and included staphylococcus (most common genus isolate ...201020018377
hydrophobin fusions for high-level transient protein expression and purification in nicotiana benthamiana.insufficient accumulation levels of recombinant proteins in plants and the lack of efficient purification methods for recovering these valuable proteins have hindered the development of plant biotechnology applications. hydrophobins are small and surface-active proteins derived from filamentous fungi that can be easily purified by a surfactant-based aqueous two-phase system. in this study, the hydrophobin hfbi sequence from trichoderma reesei was fused to green fluorescent protein (gfp) and tran ...201020018596
modal codon usage: assessing the typical codon usage of a genome.most genomes are heterogeneous in codon usage, so a codon usage study should start by defining the codon usage that is typical to the genome. although this is commonly taken to be the genomewide average, we propose that the mode-the codon usage that matches the most genes-provides a more useful approximation of the typical codon usage of a genome. we provide a method for estimating the modal codon usage, which utilizes a continuous approximation to the number of matching genes and a simplex opti ...201020018979
finding a way to the nucleus.agrobacterium species transfer single-strand dna and virulence effector proteins to plants. to understand how agrobacterium achieves interkingdom horizontal gene transfer, scientists have investigated how the interaction of bacterial effector proteins with host proteins directs t-dna to the plant nucleus. vire2, a single-strand dna binding protein, likely plays a key role in t-dna nuclear targeting. however, subcellular trafficking of vire2 remains controversial, with reports of both cytoplasmic ...201020022799
characterization of a gene family of outer membrane proteins (ropb) in rhizobium leguminosarum bv. viciae vf39sm and the role of the sensor kinase chvg in their regulation.the outer membrane of gram-negative bacteria represents the interface between the bacterium and its external environment. it has a critical role as a protective barrier against harmful substances and is also important in host-bacteria interactions representing the initial physical point of contact between the host cell and bacterial cell. ropb is a previously identified outer membrane protein from rhizobium leguminosarum bv. viciae that is present in free-living cells but absent in bacteroids (h ...201020023026
rhizobium leguminosarum hupe encodes a nickel transporter required for hydrogenase activity.synthesis of the hydrogen uptake (hup) system in rhizobium leguminosarum bv. viciae requires the function of an 18-gene cluster (hupslcdefghijk-hypabfcdex). among them, the hupe gene encodes a protein showing six transmembrane domains for which a potential role as a nickel permease has been proposed. in this paper, we further characterize the nickel transport capacity of hupe and that of the translated product of hupe2, a hydrogenase-unlinked gene identified in the r. leguminosarum genome. hupe2 ...201020023036
generation of backbone-free, low transgene copy plants by launching t-dna from the agrobacterium chromosome.in both applied and basic research, agrobacterium-mediated transformation is commonly used to introduce genes into plants. we investigated the effect of three agrobacterium tumefaciens strains and five transferred (t)-dna origins of replication on transformation frequency, transgene copy number, and the frequency of integration of non-t-dna portions of the t-dna-containing vector (backbone) into the genome of arabidopsis (arabidopsis thaliana) and maize (zea mays). launching t-dna from the pica ...201020023148
renilla luciferase-based quantitation of potato virus a infection initiated with agrobacterium infiltration of n. benthamiana leaves.a quantitation method based on the sensitive detection of renilla luciferase (rluc) activity was developed and optimized for potato virus a (pva; genus potyviridae) gene expression. this system is based on infections initiated by agrobacterium infiltration and subsequent detection of the translation of pva::rluc rna, which is enhanced by viral replication, first within the cells infected initially and later by translation and replication within new cells after spread of the virus. firefly lucife ...201020026122
genetic basis for rhizobium etli ce3 o-antigen o-methylated residues that vary according to growth conditions.the rhizobium etli ce3 o antigen is a fixed-length heteropolymer with o methylation being the predominant type of sugar modification. there are two o-methylated residues that occur, on average, once per complete o antigen: a multiply o-methylated terminal fucose and 2-o methylation of a fucose residue within a repeating unit. the amount of the methylated terminal fucose decreases and the amount of 2-o-methylfucose increases when bacteria are grown in the presence of the host plant, phaseolus vul ...201019948805
pistil drip following pollination: a simple in planta agrobacterium-mediated transformation in cotton.transgenic cotton plants were developed by pistil drip inoculation in a solution containing agrobacterium carrying a gene for resistance to the herbicide basta (bar), 10% (w/v) sucrose, 0.05% (v/v) silwet l-77 and 40 mg acetosyringone l(-1). pistil drip during 17:00-19:00 on the first day of flowering resulted in 0.07-0.17% basta-resistant plants/number of viable seeds generated, and stigma excision prior to pistil drip during this time period gave rise to a transformation efficiency of 0.46-0.9 ...201019953299
pre- and post-agroinfection strategies for efficient leaf disk transformation and regeneration of transgenic strawberry plants.following previously described agrobacterium tumefaciens-mediated transformation procedures for fragaria x ananassa duch. 'chandler', we undertook several experiments to establish the importance of some parameters affecting transformation. the most important factor that increased the percent recovery of transformants was the introduction of a pre-selection phase, in-between co-cultivation and selection, in which leaf disks were cultured on pre-selection regeneration medium containing validamycin ...201019956955
ligational behavior of thiosemicarbazone, semicarbazone and thiocarbohydrazone ligands towards vo(iv), ce(iii), th(iv) and uo2(vi) ions: synthesis, structural characterization and biological studies.mono- and binuclear vo(iv), ce(iii), th(iv) and uo(2)(vi) complexes of thiosemicarbazone, semicarbazone and thiocarbohydrazone ligands derived from 4,6-diacetylresorcinol were synthesized. the structures of these complexes were elucidated by elemental analyses, ir, uv-vis, esr, (1)h nmr and mass spectra as well as conductivity and magnetic susceptibility measurements and thermal analyses. the thiosemicarbazone (h(4)l(1)) and the semicarbazone (h(4)l(2)) ligands behave as dibasic pentadentate lig ...201019963432
agrobacterium tumefaciens-mediated transformation of guignardia citricarpa.guignardia citricarpa, the causal agent of citrus black spot, was successfully transformed via agrobacterium tumefaciens with cassettes for gfp and bar expression. transformation is essential to understand the role of genes during interaction between plants and its pathogens. using a binary plasmid vector based in the ppzp201bk, both germinated conidia and physically fragmented hyphae of g. citricarpa were transformed. eight independent transformants of g. citricarpa resistant to ammonium glifos ...201019995579
enhanced removal of polychlorinated biphenyls from alfalfa rhizosphere soil in a field study: the impact of a rhizobial inoculum.polychlorinated biphenyls (pcb) are persistent pollutants in soil environments where they continue to present considerable human health risks. successful strategies to remediate contaminated soils are needed that are effective and of low cost. bioremediation approaches that include the use of plants and microbial communities to promote degradation of pcb have significant potential but need further assessment under field conditions. the effects of growth of alfalfa (medicago sativa l.) and inocul ...201019995667
how does sulphur availability modify n acquisition of white clover (trifolium repens l.)?the role of s in legume growth, n uptake, and n2 fixation was investigated using white clover (trifolium repens l.) as a model species. we examined whether the effect of sulphate addition on n fixation resulted from a stimulation of host plant growth, a specific effect of s on nodulation, or a specific effect of s on nodule metabolism. clones of white clover, inoculated with rhizobium leguminosarum, were grown for 140 d in a hydroponic system with three levels of sulphate concentration (0 mm, 0. ...201019933318
detection of quorum sensing signal molecules and mutation of luxs gene in vibrio ichthyoenteri.some pathogenic species belonging to the vibrionaceae family have been shown to regulate virulence through a complicated network of quorum sensing systems. in this study, three kinds of n-acylhomoserine lactone (ahl) signal molecules were detected in vibrio ichthyoenteri da3, a pathogen of cultured turbot (scophthalmus maximus), with the agrobacterium tumefaciens reporter strain kyc55 (pjz372)(pjz384)(pjz410). da3 produced ahls during the entire growth phase, and the level of ahls increased, acc ...201019878720
theoretical and structural analysis of the active site of the transcriptional regulators lasr and trar, using molecular docking methodology for identifying potential analogues of acyl homoserine lactones (ahls) with anti-quorum sensing activity.in the present study the homology of transcriptional receptors luxr type were evaluated using as point of reference the receptors trar and lasr of the bacterial types agrobacterium tumefaciens and pseudomonas aureginosa respectively. a series of alignments were performed in order to demonstrate that the active site of the protein is conserved in wide range of gram negative bacteria. moreover, some docking calculations were carried out for analogs of the acyl homoserin lactones (ahls) and regulat ...201019945196
bacteria colonizing root nodules of wild legumes exhibit virulence-associated properties of mammalian pathogens.bacteria not proficient in nitrogen fixing symbiosis were proven able to invade root nodules of three wild legumes of the genus hedysarum in algeria and to be multiplying in these in place of the natural rhizobium symbionts. the involved species featured taxa known as human pathogens including: enterobacter cloacae, enterobacter kobei, escherichia vulneris, pantoea agglomerans and leclercia adecarboxylata. a direct screening of the phenotypic determinants of virulence using human cultured cells ...201019916054
electrochemical selective detection of dopamine on microbial carbohydrate-doped multiwall carbon nanotube-modified electrodes.microbial carbohydrate-doped multiwall carbon nanotube (mwnt)-modified electrodes were prepared for the purpose of determining if 4-(2-aminoethyl)benzene-1,2-diol (3,4-dihydroxyphenylalanine; dopamine) exists in the presence of 0.5 mm ascorbic acid, a representative interfering agent in neurotransmitter detection. the microbial carbohydrate dopants were alpha-cyclosophorohexadecaose (alpha-c16) from xanthomonas oryzae and cyclic-(1 --> 2)-beta-d-glucan (cys) from rhizobium meliloti. the cyclic v ...201019921114
identification in agrobacterium tumefaciens of the d-galacturonic acid dehydrogenase gene.there are at least three different pathways for the catabolism of d-galacturonate in microorganisms. in the oxidative pathway, which was described in some prokaryotic species, d-galacturonate is first oxidised to meso-galactarate (mucate) by a nicotinamide adenine dinucleotide (nad)-dependent dehydrogenase (ec 1.1.1.203). in the following steps of the pathway mucate is converted to 2-keto-glutarate. the enzyme activities of this catabolic pathway have been described while the corresponding gene ...201019921179
efficient transformation of kalanchoe blossfeldiana and production of male-sterile plants by engineered anther ablation.engineered male sterility in ornamental plants has many applications such as facilitate hybrid seed production, eliminate pollen allergens, reduce the need for deadheading to extend the flowering period, redirect resources from seeds to vegetative growth, increase flower longevity and prevent gene flow between genetically modified and related native plants. we have developed a reliable and efficient agrobacterium-mediated protocol for the genetic transformation of different kalanchoe blossfeldia ...201019921199
high level protein expression in plants through the use of a novel autonomously replicating geminivirus shuttle vector.we constructed a novel autonomously replicating gene expression shuttle vector, with the aim of developing a system for transiently expressing proteins at levels useful for commercial production of vaccines and other proteins in plants. the vector, pric, is based on the mild strain of the geminivirus bean yellow dwarf virus (beydv-m) and is replicationally released into plant cells from a recombinant agrobacterium tumefaciens ti plasmid. pric differs from most other geminivirus-based vectors in ...201019929900
analysis of the mucr gene regulating biosynthesis of exopolysaccharides: implications for biofilm formation in sinorhizobium meliloti rm1021.bacterial surface polysaccharides are crucial for establishment of successful rhizobia-legume symbiosis, and in most bacteria, are also critical for biofilm formation and surface colonization. in sinorhizobium meliloti, the regulatory protein mucr controls exopolysaccharide production. to clarify the relationship between exopolysaccharide synthesis and biofilm formation, we studied mucr expression under growth conditions that influence attachment to polyvinylchloride, developed a microtiter plat ...201019929968
potatovirus x and tobacco mosaic virus-based vectors compatible with the gateway cloning system.virus-based expression vectors are important tools for high-level production of foreign proteins and for gene function analysis through virus induced gene silencing. to exploit further their advantages as fast, high yield replicons, a set of vectors was produced by converting and adapting potato virus x (pvx) and tobacco mosaic virus (tmv)-based vectors to allow easy cloning of foreign sequences by the gateway cloning system. target genes were cloned efficiently by recombination and successfully ...201019903495
tropane alkaloid profiling of hydroponic datura innoxia mill. plants inoculated with agrobacterium rhizogenes.hydroponics has been shown as a possible way to produce high quality plant biomass with improved phytochemical levels. nevertheless, effects of plant biotic and abiotic environment can lead to drastic changes and plant growth conditions must be optimised.201019904728
establishment of a system based on universal multiplex-pcr for screening genetically modified crops.the rapid development of many genetically modified (gm) crops in the past two decades makes it necessary to introduce an alternative strategy for routine screening and identification. in this study, we established a universal multiplex pcr detection system which will effectively reduce the number of reactions needed for sample identification. the pcr targets of this system include the six most frequently used transgenic elements: cauliflower mosaic virus (camv) 35s promoter, agrobacterium tumefa ...201019855961
the use of 35s and tnos expression elements in the measurement of genetically engineered plant materials.an online survey was conducted by the international life sciences institute, food biotechnology committee, on the use of qualitative and quantitative polymerase chain reaction (pcr) assays for cauliflower mosaic virus 35s promoter and agrobacterium tumefaciens tnos dna sequence elements for the detection of genetically engineered (ge) crop plant material. forty-four testing laboratories around the world completed the survey. the results showed the widespread use of such methods, the multiplicity ...201019856176
mutational analysis of the active site residues of a d: -psicose 3-epimerase from agrobacterium tumefaciens.d-psicose 3-epimerase from agrobacterium tumefacience catalyzes the conversion of d: -fructose to d-psicose. according to mutational analysis, the ring at position 112, the negative charge at position 156, and the positive charge at position 215 were essential components for enzyme activity and for binding fructose and psicose. the surface contact area and distance to the bound substrate by molecular modeling suggest that the positive charge of arg215 was involved in stabilization of cis-endiol ...201019859667
high-level expression of camelid nanobodies in nicotiana benthamiana.nanobodies (or vhhs) are single-domain antigen-binding fragments derived from camelid heavy chain-only antibodies. their small size, monomeric behaviour, high stability and solubility, and ability to bind epitopes not accessible to conventional antibodies make them especially suitable for many therapeutic and biotechnological applications. here we describe high-level expression, in nicotiana benthamiana, of three versions of an anti-hen egg white lysozyme (hewl) nanobody which include the origin ...201019862637
transformation of the water soluble fraction from "alpeorujo" by coriolopsis rigida: the role of laccase in the process and its impact on azospirillum brasiliense survival.the objective of this work was to evaluate the ability of the white rot basidiomycete coriolopsis rigida to detoxify the water soluble fraction from "alpeorujo" (wsfa), a solid by-product produced by the olive oil extraction industry and characterized by a high concentration of phenols which limits its use as fertilizer and/or amendment. c. rigida reduced the phenol content in the liquid media supplemented with wsfa at 10 and 20% (v/v) after 15d of incubation. the analysis of wsfa toxicity after ...201019875147
ensifer, phyllobacterium and rhizobium species occupy nodules of medicago sativa (alfalfa) and melilotus alba (sweet clover) grown at a canadian site without a history of cultivation.phage-resistant and -susceptible bacteria from nodules of alfalfa and sweet clover, grown at a site without a known history of cultivation, were identified as diverse genotypes of ensifer, rhizobium and phyllobacterium species based on sequence analysis of ribosomal (16s and 23s rrna) and protein-encoding (atpd and reca) genes, southern hybridization/rflp and a range of phenotypic characteristics. among phage-resistant bacteria, one genotype of rhizobium sp. predominated on alfalfa (frequency ap ...201019875436
salt sensitivity in chickpea.the growth of chickpea (cicer arietinum l.) is very sensitive to salinity, with the most susceptible genotypes dying in just 25 mm nacl and resistant genotypes unlikely to survive 100 mm nacl in hydroponics; germination is more tolerant with some genotypes tolerating 320 mm nacl. when growing in a saline medium, cl(-), which is secreted from glandular hairs on leaves, stems and pods, is present in higher concentrations in shoots than na(+). salinity reduces the amount of water extractable from s ...201019843257
site-directed mutation at residues near the catalytic site of histamine dehydrogenase from nocardioides simplex and its effects on substrate inhibition.histamine dehydrogenase from nocardioides simplex (nhmdh) is a homodimer containing one 6-s-cysteinyl fmn (cfmn) and one [4fe-4s] cluster per monomer. nhmdh catalyses the oxidative deamination of histamine to ammonia and imidazole acetaldehyde, but histamine inhibits its catalytic activity at high concentrations. we mutated gene-encoded residues (tyr180, gly268 and asp269) near cfmn to understand the biophysical meaning of the substrate inhibition. three mutants y180f, g268d/d269c and y180f/g268 ...201019846434
a. tumefaciens-mediated transient expression as a tool for antigen production for cucurbit yellow stunting disorder virus.the emerging importance of criniviruses, together with their limited characterisation, necessitates the development of simple tools to enable rapid detection and monitoring in case of an outbreak. while serological tools would be ideal, criniviruses are notoriously difficult to purify and traditional methods of antibody production, requiring purified virus particles, are extremely challenging. the development of a novel molecular strategy for in planta viral antigen preparation to bypass particl ...201019819262
experimental evidences of psym transfer in a native peanut-associated rhizobia.in previous works we have characterized the native bacterial diversity associated with root nodules of peanut grown in córdoba province, argentina. studies performed in the isolate rhizobium sp. net30 revealed a phylogenetic incongruence between housekeeping and nodulation genes. this discrepancy could be explained by the horizontal transfer of nodulation genes from the native peanut isolate rhizobium sp. ncha22, a bacterium that showed high identity percentages with rhizobium tropici iib strain ...201019853428
intergenomic epistasis and coevolutionary constraint in plants and rhizobia.studying how the fitness benefits of mutualism differ among a wide range of partner genotypes, and at multiple spatial scales, can shed light on the processes that maintain mutualism and structure coevolutionary interactions. using legumes and rhizobia from three natural populations, i studied the symbiotic fitness benefits for both partners in 108 plant maternal family by rhizobium strain combinations. genotype-by-genotype (g x g) interactions among local genotypes and among partner populations ...201020002161
crystal structure and substrate specificity of plant adenylate isopentenyltransferase from humulus lupulus: distinctive binding affinity for purine and pyrimidine nucleotides.cytokinins are important plant hormones, and their biosynthesis most begins with the transfer of isopentenyl group from dimethylallyl diphosphate (dmapp) to the n6-amino group of adenine by either adenylate isopentenyltransferase (aipt) or trna-ipt. plant aipts use atp/adp as an isopentenyl acceptor and bacterial aipts prefer amp, whereas trna-ipts act on specific sites of trna. here, we present the crystal structure of an aipt-atp complex from humulus lupulus (hlaipt), which is similar to the p ...201020007608
characterization of the nifa-rpon regulon in rhizobium etli in free life and in symbiosis with phaseolus vulgaris.the nifa-rpon complex is a master regulator of the nitrogen fixation genes in alphaproteobacteria. based on the complete rhizobium etli genome sequence, we constructed an r. etli cfn42 oligonucleotide (70-mer) microarray and utilized this tool, reverse transcription (rt)-pcr analysis (transcriptomics), proteomics, and bioinformatics to decipher the nifa-rpon regulon under microaerobic conditions (free life) and in symbiosis with bean plants. the r. etli nifa-rpon regulon was determined to contai ...201020453139
agrobacterium rhizogenes-mediated transformation of a high oil-producing filamentous fungus umbelopsis isabellina.the agrobacterium rhizogenes-mediated transformation procedure was developed by using the hygromycin b phosphotransferase gene (hph) as a selective marker for the oil-producing fungus umbelopsis isabellina. different conditions were combined to increase the transformation efficiency. the highest efficiency was obtained by using a. rhizogenes strain r105 and a vector with zygomycete promoter. southern blot analysis demonstrated that 71% of transformants contained random integrations of t-dna sequ ...201020453313
a method to confer salinity stress tolerance to plants by helicase overexpression.high salinity stress adversely affects plant growth and limits agricultural production worldwide. to minimize these losses it is essential to develop stress-tolerant plants. several genes, including the genes encoding for helicases, are induced in response to salinity stress. helicases are ubiquitous motor enzymes that catalyze the unwinding of energetically stable duplex dna (dna helicases) or duplex rna secondary structures (rna helicases) in an atp-dependent manner. helicase members of dead-b ...201020225163
agrobacterium induces expression of a host f-box protein required for tumorigenicity.agrobacterium exports dna into plant cells, eliciting neoplastic growths on many plant species. during this process, a skp1-cdc53-cullin-f-box (scf) complex that contains the bacterial virulence f-box protein virf facilitates genetic transformation by targeting for proteolysis proteins, the agrobacterium protein vire2 and the host protein vip1, that coat the transferred dna. however, some plant species do not require virf for transformation. here, we show that agrobacterium induces expression of ...201020227663
improvement of phosphate solubilization and medicago plant yield by an indole-3-acetic acid-overproducing strain of sinorhizobium meliloti.nitrogen (n) and phosphorus (p) are the most limiting factors for plant growth. some microorganisms improve the uptake and availability of n and p, minimizing chemical fertilizer dependence. it has been published that the rd64 strain, a sinorhizobium meliloti 1021 strain engineered to overproduce indole-3-acetic acid (iaa), showed improved nitrogen fixation ability compared to the wild-type 1021 strain. here, we present data showing that rd64 is also highly effective in mobilizing p from insolub ...201020511434
influence of soil fumigation by methyl bromide and methyl iodide on rhizosphere and phyllosphere microbial community structure.rhizosphere and phyllosphere microbial communities were evaluated on roots and leaves of growth chamber-grown lettuce (lactuca sativa (l.) cv. green forest) plants by culture-dependent and -independent methods after soil fumigation. denaturing gradient gel electrophoresis (dgge) with 16s rrna primers followed by cloning and sequencing was used to identify major rrna bands from the rhizosphere and phyllosphere. three weeks after fumigation, there were no differences (p = 0.16) in rhizosphere micr ...201020512733
rhizobium kunmingense sp. nov., isolated from rhizosphere soil of camptotheca acuminata decne.strain lxd30(t) was isolated from rhizosphere soil of a plant of the species camptotheca acuminata decne which is native to warm, humid stream banks in southern china. analysis of the 16s rrna gene sequence revealed that the gram-negative, rod-shaped bacterium fell within the realm of the genus rhizobium and was most closely related to rhizobium huautlense so2(t) (96.4% sequence similarity) and rhizobium cellulosilyticum lmg 23642(t) (96.4%). the isolate grew optimally at ph7.0 and 25-28 degrees ...201020513962
production of pharmaceutical-grade recombinant aprotinin and a monoclonal antibody product using plant-based transient expression systems.plants have been proposed as an attractive alternative for pharmaceutical protein production to current mammalian or microbial cell-based systems. eukaryotic protein processing coupled with reduced production costs and low risk for mammalian pathogen contamination and other impurities have led many to predict that agricultural systems may offer the next wave for pharmaceutical product production. however, for this to become a reality, the quality of products produced at a relevant scale must equ ...201020514694
[induction and in vitro culture of wedelia trilobata hairy roots].to study the possibilities for improvement of the ornamental character and production of secondary metabolites by using wedelia trilobata hairy roots, we investigated the induction of w. trilobata l. hairy roots and its consumption changes of carbon resource, nitrogen resource, phosphate and calcium in the medium during liquid culture. the results showed that hairy roots could be incited from the cut edges of leaf explants 7 days after inoculation with agrobacterium rhizogenes atcc15834 and coul ...201020518352
polyphasic analysis of the bacterial community in the rhizosphere and roots of cyperus rotundus l. grown in a petroleum-contaminated soil.cyperus rotundus l. is a perennial herb which was found prevailing in an area in the northeast of brazil previously contaminated with petroleum. in order to enlarge the knowledge of microorganism-plant interaction in phytoremediation, the bacterial community present in the rhizosphere and roots of c. rotundus was evaluated by culture-dependent and molecular approaches. pcr-dgge analyses based on the 16s rrna gene showed that the profiles of bulk soil, rhizosphere and root samples had a high degr ...201020519908
rapid and efficient identification of agrobacterium species by reca allele analysis: agrobacterium reca diversity.the analysis of housekeeping reca gene sequences from 138 strains from 13 species or genomic species of agrobacterium, nine being biovar 1 genomospecies, and the others agrobacterium larrymoorei, agrobacterium rubi, agrobacterium sp. ncppb 1650, and agrobacterium vitis and one "former" agrobacterium species, rhizobium rhizogenes, led to the identification of 50 different reca alleles and to a clear delineation of the 14 species or genomospecies entirely consistent with that obtained by amplified ...201020521039
characterization of swarming motility in rhizobium leguminosarum bv. viciae.we have characterized swarming motility in rhizobium leguminosarum strains 3841 and vf39sm. swarming was dependent on growth on energy-rich media, and both agar concentration and incubation temperature were critical parameters for surface migration. a cell density-dependent lag period was observed before swarming motility was initiated. surface migration began 3-5 days after inoculation and a full swarming phenotype was observed 3 weeks after inoculation. the swarming front was preceded by a cle ...201020455952
nodulation and nitrogen fixation by mimosa spp. in the cerrado and caatinga biomes of brazil.*an extensive survey of nodulation in the legume genus mimosa was undertaken in two major biomes in brazil, the cerrado and the caatinga, in both of which there are high degrees of endemicity of the genus. *nodules were collected from 67 of the 70 mimosa spp. found. thirteen of the species were newly reported as nodulating. nodules were examined by light and electron microscopy, and all except for m. gatesiae had a structure typical of effective mimosa nodules. the endosymbiotic bacteria in nodu ...201020456044
multiple evolutionary origins of legume traits leading to extreme rhizobial differentiation.summary: *when rhizobia differentiate inside legume host nodules to become nitrogen-fixing bacteroids, they undergo a physiological as well as a morphological transformation. these transformations are more extreme in some legume species than others, leading to fundamental differences in rhizobial life history and evolution. here, we analysed the distribution of different bacteroid morphologies over a legume phylogeny to understand the evolutionary history of this host-influenced differentiation. ...201020456052
mutation of outer-shell residues modulates metal ion co-ordination strength in a metalloenzyme.the metal ion co-ordination sites of many metalloproteins have been characterized by a variety of spectroscopic techniques and small-molecule model systems, revealing many important insights into the structural determinants of metal ion co-ordination. however, our understanding of this fundamentally and practically important phenomenon remains frustratingly simplistic; in many proteins it is essentially impossible to predict metal ion specificity and the effects of remote 'outer-shell' residues ...201020459397
expression of an immunogenic f1-v fusion protein in lettuce as a plant-based vaccine against plague.yersinia pestis is a pathogenic agent that causes the bubonic and pneumonic plague. the development of an efficient and low-cost oral vaccine against these diseases is highly desirable. in this study, the immunogenic fusion protein f1-v from y. pestis was introduced into lettuce via agrobacterium-mediated transformation, and putative transgenic lines were developed. the presence of the transgene in these putative transgenic lines was determined using polymerase chain reaction (pcr), and transgen ...201020461403
expression of the fluorescent proteins dsred and egfp to visualize early events of colonization of the chickpea blight fungus ascochyta rabiei.ascochyta blight caused by the ascomycete fungus ascochyta rabiei, is a major biotic constraint of chickpea (cicer arietinum l.), resulting in disastrous crop losses worldwide. to study early stages of development and pathogenic mechanisms of the fungus, two binary vectors for the constitutive expression of the red fluorescent protein (dsred-express) and the green fluorescent protein (egfp1) were constructed. furthermore, we have developed an improved and highly reproducible agrobacterium tumefa ...201020461519
the chitinase gene (bbchit1) from beauveria bassiana enhances resistance to cytospora chrysosperma in populus tomentosa carr.the chinese white poplar (populus tomentosa carr.) is susceptible to infection by plant diseases which severely affect its growth and substantially decrease its economic value. a chitinase gene (bbchit1) from beauveria bassiana was introduced into chinese white poplar (populus tomentosa carr.) by agrobacterium-mediated transformation. the t-dna of plant transformation vector contained the beta-glucuronidase reporter gene (gus) under the control of camv 35s promoter and the neomycin phosphotransf ...201020464449
an improved agrobacterium-mediated transformation system for the functional genetic analysis of penicillium marneffei.we have developed an improved agrobacterium-mediated transformation (amt) system for the functional genetic analysis of penicillium marneffei, a thermally dimorphic, human pathogenic fungus. our amt protocol included the use of conidia or pre-germinated conidia of p. marneffei as the host recipient for t-dna from agrobacterium tumefaciens and co-cultivation at 28°c for 36 hours. bleomycin-resistant transformants were selected as yeast-like colonies following incubation at 37°c. the efficiency of ...201020465521
1-deoxynojirimycins with dansyl capped n-substituents as probes for morbus gaucher affected cell lines.cyclization by double reductive amination of d-xylo-hexos-5-ulose with methyl 6-aminohexanoate gave (methoxycarbonyl)pentyl-1-deoxynojirimycin. reaction of the terminal carboxylic acid with n-dansyl-1,6-diaminohexane provided the corresponding chain-extended fluorescent derivative. by reaction with bis(6-dansylaminohexyl)amine, the corresponding branched di-n-dansyl compound was obtained. both compounds are strong inhibitors of d-glucosidases and could also be shown to distinctly improve, at sub ...201020471633
novel functions of stomatal cytokinesis-defective 1 (scd1) in innate immune responses against bacteria.eukaryotes employ complex immune mechanisms for protection against microbial pathogens. here, we identified scd1 (stomatal cytokinesis-defective 1), previously implicated in growth and development through its role in cytokinesis and polarized cell expansion (falbel, t. g., koch, l. m., nadeau, j. a., segui-simarro, j. m., sack, f. d., and bednarek, s. y. (2003) development 130, 4011-4024) as a novel component of innate immunity. in arabidopsis, scd1 is a unique gene encoding for the only protein ...201020472560
genetic and metabolic divergence within a rhizobium leguminosarum bv. trifolii population recovered from clover nodules.rhizobia are able to establish symbiosis with leguminous plants and usually occupy highly complex soil habitats. the large size and complexity of their genomes are considered advantageous, possibly enhancing their metabolic and adaptive potential and, in consequence, their competitiveness. a population of rhizobium leguminosarum bv. trifolii organisms recovered from nodules of several clover plants growing in each other's vicinity in the soil was examined regarding possible relationships between ...201020472725
vip1: linking agrobacterium-mediated transformation to plant immunity?agrobacterium tumefaciens is the most efficient vehicle used today for the production of transgenic plants and plays an essential role in basic scientific research and in agricultural biotechnology. previously, plant vire2-interacting protein 1 (vip1) was shown to play a role in agrobacterium-mediated transformation. recent reports demonstrate that vip1, as one of the bzip transcription factors, is also involved in plant immunity responses. agrobacterium is able to activate and abuse vip1 for tr ...201020473505
high-yield production, refolding and a molecular modelling of the catalytic module of (1,3)-beta-d-glucan (curdlan) synthase from agrobacterium sp.biosynthesis of the (1,3)-beta-d: -glucan (curdlan) in agrobacterium sp., is believed to proceed by the repetitive addition of glucosyl residues from udp-glucose by a membrane-embedded curdlan synthase (crds) [udp-glucose: (1,3)-beta-d: -glucan 3-beta-d: -glucosyltransferase; ec 2.4.1.34]. the catalytic module of crds (cm-crds) was expressed in good yield from a cdna encoding cm-crds cloned into the pet-32a(+) vector, containing a coding region for thioredoxin, and from the champion pet sumo sys ...201020473714
rapid, high-yield production in plants of individualized idiotype vaccines for non-hodgkin's lymphoma.animal and clinical studies with plant-produced single-chain variable fragment lymphoma vaccines have demonstrated specific immunogenicity and safety. however, the expression levels of such fragments were highly variable and required complex engineering of the linkers. moreover, the downstream processing could not be built around standard methods like protein a affinity capture.201020494963
a high-conductance cation channel from the inner membrane of the free-living soil bacteria rhizobium etli.in this communication we reported the study of a cation channel present in the cytoplasmic membrane of the nitrogen fixing bacterium rhizobium etli. inner-membrane (im) vesicles were purified and fused into planar lipid bilayers (plbs), under voltage clamp conditions. we have found that fusion of im-enriched vesicle fractions with these model membranes leads, mainly (>30% of 46 experiments), to the reconstitution of high-conductance channels. following this strategy, the activity of a channel wi ...201020502878
interactions of botryococcus braunii cultures with bacterial biofilms.unicellular microalgae generally grow in the presence of bacteria, particularly when they are farmed massively. this study analyzes the bacteria associated with mass culture of botryococcus braunii: both the planktonic bacteria in the water column and those forming biofilms adhered to the surface of the microalgal cells (∼10⁷-10⁸ culturable cells per gram microalgae). furthermore, we identified the culturable bacteria forming a biofilm in the microalgal cells by 16s rdna sequencing. at least eig ...201020502890
crystal structure of exotype alginate lyase atu3025 from agrobacterium tumefaciens.alginate, a major component of the cell wall matrix in brown seaweeds, is degraded by alginate lyases through a beta-elimination reaction. almost all alginate lyases act endolytically on substrate, thereby yielding unsaturated oligouronic acids having 4-deoxy-l-erythro-hex-4-enepyranosyluronic acid at the nonreducing end. in contrast, agrobacterium tumefaciens alginate lyase atu3025, a member of polysaccharide lyase family 15, acts on alginate polysaccharides and oligosaccharides exolytically an ...201020507980
the small subunit arob of arsenite oxidase: lessons on the [2fe-2s] rieske protein superfamily.here, we describe the characterization of the [2fe-2s] clusters of arsenite oxidases from rhizobium sp. nt-26 and ralstonia sp. 22. both reduced rieske proteins feature epr signals similar to their homologs from rieske-cyt b complexes, with g values at 2.027, 1.88, and 1.77. redox titrations in a range of ph values showed that both [2fe-2s] centers have constant e(m) values up to ph 8 at approximately +210 mv. above this ph value, the e(m) values of both centers are ph-dependent, similar to what ...201020421651
isolation and partial characterization of bacterial strains on low organic carbon medium from soils fertilized with different organic amendments.a total of 720 bacterial strains were isolated from soils with four different organic amendment regimes on a low organic carbon (low-c) agar medium (10 µg c ml(-1)) traditionally used for isolation of oligotrophs. organic amendments in combination with field history resulted in differences in dissolved organic carbon contents in these soils. there were negative correlations between total and dissolved organic carbon content and the number of isolates on low-c agar medium, whereas these correlati ...201020422409
new approaches to enzymatic glycoside synthesis through directed evolution.the expanding field of glycobiology requires tools for the synthesis of structurally defined oligosaccharides and glycoconjugates, while any potential therapeutic applications of sugar-based derivates would require access to substantial quantities of such compounds. classical chemical approaches are not well suited for such large-scale syntheses, thus enzymatic approaches are sought. traditional routes to the enzymatic assembly of oligosaccharides have involved the use of either nature's own bio ...201020427037
the small heat-shock protein hspl is a virb8 chaperone promoting type iv secretion-mediated dna transfer.agrobacterium tumefaciens is a plant pathogen that utilizes a type iv secretion system (t4ss) to transfer dna and effector proteins into host cells. in this study we discovered that an alpha-crystallin type small heat-shock protein (alpha-hsp), hspl, is a molecular chaperone for virb8, a t4ss assembly factor. hspl is a typical alpha-hsp capable of protecting the heat-labile model substrate citrate synthase from thermal aggregation. it forms oligomers in a concentration-dependent manner in vitro. ...201020427270
impact of nutrient components on production of the phytoestrogens daidzein and genistein by hairy roots of psoralea corylifolia.transformed hairy roots of psoralea corylifolia were established by infection with agrobacterium rhizogenes lba 9402. the aim of this work was to elucidate the effects of media constituents on production of the phytoestrogenic isoflavones daidzein and genistein. a. rhizogenes strain lba 9402 harboring ri plasmid was used to transform stem segments of in vitro seedlings. the resultant hairy roots were confirmed by polymerase chain reaction (pcr) and exhibited ri t-dna. transformed hairy root clon ...201020428956
an efficient in vitro-inoculation method for tomato yellow leaf curl virus.tomato yellow leaf curl virus (tylcv) is a member of the family geminiviridae, genus begomovirus. to test the infectivity of tylcv in tomato plants, an improved protocol for inoculation of in vitro-cultured tomato plants was developed.201020429892
analysis of the mechanism of action of the antisense rna that controls the replication of the repabc plasmid p42d.replication and segregation of the rhizobium etli symbiotic plasmid (pretcfn42d) depend on the presence of a repabc operon, which carries all the plasmid-encoded elements required for these functions. all repabc operons share three protein-encoding genes (repa, repb, and repc), an antisense rna (ctrna) coding gene, and at least one centromere-like region (pars). the products of repa and repb, in conjunction with the pars region, make up the segregation system, and they negatively regulate operon ...201020435728
proteomic and transcriptomic characterization of a virulence-deficient phosphatidylcholine-negative agrobacterium tumefaciens mutant.phosphatidylcholine (pc) is the most abundant phospholipid in eukaryotic membranes, whereas only a limited number of bacteria are able to synthesize pc. intriguingly, many of the bacteria with pc-containing membranes interact with eukaryotic hosts. pc is one of the major membrane lipids in the phytopathogenic bacterium agrobacterium tumefaciens. the presence of pc is critical for diverse cellular processes like motility, biofilm formation, stress resistance, and virulence. the exact role of pc i ...201020437057
fast technique for agrobacterium-mediated transient gene expression in seedlings of arabidopsis and other plant species.genome sequencing has identified a massive number of uncharacterized genes in arabidopsis thaliana and several other plant species. to decipher these unknown gene functions, several transient expression assays have been developed as rapid and convenient alternatives to the lengthy creation of transgenic plants. as one of these transient assays, agrobacterium-mediated transformation harnesses the natural capability of agrobacterium to transfer foreign dna into plant cells with intact cell walls. ...201020439415
agrobacterium-mediated transformation of euphorbia tirucalli callus.in order to establish a basis for transformation technology in the petroleum plant euphorbia tirucalli, the callus of the plant was infected with agrobacterium, washed with distilled water, sterilized with distilled water containing 100 mg/l of carbenicillin, selected on solidified b5 medium containing 13 mg/l of g418 and 100 mg/l of carbenicillin, and then on solidified b5 medium containing 25 mg/l of g418 and 100 mg/l of carbenicillin for the transgenic calli, and then the callus lines were su ...201020445322
lotus endemic to the canary islands are nodulated by diverse and novel rhizobial species and symbiotypes.genetic and symbiotic characterization of 34 isolates from several lotus species endemic to the canary islands showed extraordinary diversity, with bacteria belonging to different species of the genera mesorhizobium (17 isolates), sinorhizobium (12 isolates) and rhizobium/agrobacterium (5 isolates). in a previous report, we showed that the sinorhizobium isolates mostly belonged to s. meliloti. here, we focused on the remaining isolates. the lotus mesorhizobial strains were distributed in the rrs ...201020447791
resonance assignments of the nucleotide-free wildtype mlok1 cyclic nucleotide-binding domain.cyclic nucleotide-sensitive ion channels, known as hcn and cng channels play crucial roles in neuronal excitability and signal transduction of sensory cells. these channels are activated by binding of cyclic nucleotides to their intracellular cyclic nucleotide-binding domain (cnbd). a comparison of the structures of wildtype ligand-free and ligand-bound cnbd is essential to elucidate the mechanism underlying nucleotide-dependent activation of cnbds. we recently reported the solution structure of ...201020449776
sinorhizobium versus ensifer: may a taxonomy subcommittee of the icsp contradict the judicial commission?in response to a request for an opinion, the judicial commission (opinion 84) confirmed the earlier synonym, ensifer, as the correct name for the genus better known as sinorhizobium. the judicial commission considered that this decision would not cause sufficient confusion to justify the conservation of the latter name. the subcommittee on the taxonomy of agrobacterium and rhizobium of the international committee on systematics of prokaryotes (icsp) publicly disagreed with this conclusion. was i ...201020453103
challenging semi-bootstrapping molecular-replacement strategy reveals intriguing crystal packing of rhizavidin.the structure of rhizavidin, the first dimeric member of the avidin family which maintains high affinity towards biotin, was determined to high resolution by semet sad. consequently, the structure of the rhizavidin-biotin complex was determined by molecular-replacement methods using the apo structure as the search model; this ran into complications and required combined programs as well as bootstrapping approaches. although present as a dimer in solution, rhizavidin packs as unique oligomers in ...201020383003
metabolic engineering of glyoxalase pathway for enhancing stress tolerance in plants.glyoxalase system consists of two enzymes glyoxalase i (gly i) and glyoxalase ii (gly ii). gly i detoxifies methylglyoxal (mg), a cytotoxic byproduct of glycolysis, to s-lactoylglutathione (slg) where it uses one molecule of reduced glutathione. subsequently, slg is converted to lactate by gly ii and one molecule of reduced glutathione is recycled back into the system. the level of mg, which is produced ubiquitously in all living organisms, is enhanced upon exposure to different abiotic stresses ...201020387042
functional characterization of water-deficit stress responsive genes using rnai.in response to water-deficit stress, plants alter expression of thousands of genes and as a result, cellular, physiological, and biochemical processes are modified. understanding the functional role of water-deficit stress-responsive genes is important in order to develop stress-tolerant plants. rna interference (rnai) technology is one of the potential reverse genetics tool for assessing the functional significance of these genes. we describe here the protocols for developing stable gene knockd ...201020387047
[soil microbial properties under different vegetation types in loess hilly region].by using fumigation-extract (fe) method and biolog ecoplate, this paper investigated the microbial biomass and diversity in 0-20 cm soil layer under five vegetation types, including artificial woodland, shrubland, cropland, abandoned farmland, and natural grassland, in dingxi of gansu province. in the meanwhile, the relationships between soil microbes and soil nutrients were studied by path analysis, and the five typical vegetation types were evaluated from the aspect of soil microbes. relative ...201020387439
Displaying items 10101 - 10200 of 10619