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Isaria javanica pf185 is an important entomopathogenic fungus with potential for use as an agricultural biocontrol agent. However, the effect of I. javanica pf185 on plant growth is unknown. Enhanced tobacco growth was observed when tobacco roots were exposed to spores, cultures, and fungal cell-free culture supernatants of this fungus. Tobacco seedlings were also exposed to the volatiles of I. javanica pf185 in vitro using I-plates in which the plant and fungus were growing in separate compartments connected only by air space. The length and weight of seedlings, content of leaf chlorophyll, and number of root branches were significantly increased by the fungal volatiles. Heptane, 3-hexanone, 2,4-dimethylhexane, and 2-nonanone were detected, by solid-phase micro-extraction and gas chromatography- mass spectrophotometry, as the key volatile compounds produced by I. javanica pf185. These findings illustrate that I. javanica pf185 can be used to promote plant growth, and also as a biocontrol agent of insect and plant diseases. Further studies are necessary to elucidate the mechanisms by which I. javanica pf185 promotes plant growth. [ABSTRACT FROM AUTHOR]

In a plasma discharge system, the power loss at powered line, matching network, and other transmission line can affect the discharge characteristics such as the power transfer efficiency, voltage and current at powered electrode, and plasma density. In this paper, we propose a method to reduce power loss by using a step down transformer mounted between the matching network and the powered electrode in a capacitively coupled argon plasma. This step down transformer decreases the power loss by reducing the current flowing through the matching network and transmission line. As a result, the power transfer efficiency was increased about 5%-10% by using a step down transformer. However, the plasma density was dramatically increased compared to no transformer. This can be understood by the increase in ohmic heating and the decrease in dc-self bias. By simply mounting a transformer, improvement of discharge efficiency can be achieved in capacitively coupled plasmas. [ABSTRACT FROM AUTHOR]

The electrical probe diagnostics are very hard to be applied to atmospheric plasmas due to severe perturbation by the electrical probes. To overcome this, the probe for measuring electron temperature and ion current density is indirectly contacted with an atmospheric jet source. The plasma parameters are obtained by using floating harmonic analysis. The probe is mounted on the quartz tube that surrounds plasma. When a sinusoidal voltage is applied to a probe contacting on a quartz tube, the electrons near the sheath at dielectric tube are collected and the probe current has harmonic components due to probe sheath nonlinearity. From the relation of the harmonic currents and amplitude of the sheath voltage, the electron temperature near the wall can be obtained with collisional sheath model. The electron temperatures and ion current densities measured at the discharge region are in the ranges of 2.7-3.4 eV and 1.7-5.2 mA/cm² at various flow rates and input powers. [ABSTRACT FROM AUTHOR]

Vibrational temperature (Tvib) of N2 gas and electron energy distribution function (EEDF) were measured in Ar/N2 mixture inductively coupled plasma (ICP). At a low gas pressure of 5 mTorr where the EEDF is bi-Maxwellian distribution, plasma density np and Tvib (from 7000 K to 5600 K) slightly decrease. However, remarkable decrease in np and Tvib is found with the dilution of N2 gas at a high gas pressure of 50 mTorr, where the EEDF is depleted Maxwellian distribution at a fixed ICP power of 150 W. When the ICP power increases from 150 W to 300 W at the gas pressure of 50 mTorr, the depleted tail on the EEDF is replenished, while np is little changed with the dilution of N2 gas. In this case, Tvib slightly decreases from 9500 K to 7600 K. These results indicate that the variation of Tvib is strongly correlated to the plasma parameters, such as the plasma density and EEDF. [ABSTRACT FROM AUTHOR]

The gap length effect on plasma parameters is investigated in a planar type inductively coupled plasma at various conditions. The spatial profiles of ion densities and the electron temperatures on the wafer level are measured with a 2D probe array based on the floating harmonic method. At low pressures, the spatial profiles of the plasma parameters rarely changed by various gap lengths, which indicates that nonlocal kinetics are dominant at low pressures. However, at relatively high pressures, the spatial profiles of the plasma parameter changed dramatically. These plasma distribution profile characteristics should be considered for plasma reactor design and processing setup, and can be explained by the diffusion of charged particles and the local kinetics. [ABSTRACT FROM AUTHOR]

The total energy lost per electron-ion pair lost εT is investigated with the electron energy distribution function (EEDF). The EEDFs are measured at various argon powers in RF inductively coupled plasma, and the EEDFs show a depleted distribution (a discontinuity occurring at the minimum argon excitation threshold energy level) with the bulk temperature and the tail temperature. The total energy loss per electron-ion pair lost εT is calculated from a power balance model with the Maxwellian EEDFs and the depleted EEDFs and then compared with the measured εT from the floating probe. It is concluded that the small population of the depleted high energy electrons dramatically increases the collisional energy loss, and the calculated eT from the depleted EEDFs has a value that is similar to the measured εT. [ABSTRACT FROM AUTHOR]

While environmental vibrations are usually in the range of a few hundred Hertz, small-form-factor piezoelectric vibration energy harvesters will have higher resonant frequencies due to the structural size effect. To address this issue, we propose a resonant frequency-down conversion based on the theory of dynamic vibration absorber for the design of a small-form-factor piezoelectric vibration energy harvester. The proposed energy harvester consists of two frequency-tuned elastic components for lowering the first resonant frequency of an integrated system but is so configured that an energy harvesting beam component is inverted with respect to the other supporting beam component for a small form factor. Furthermore, in order to change the unwanted modal characteristic of small separation of resonant frequencies, as is the case with an inverted configuration, a proof mass on the supporting beam component is slightly shifted toward a second proof mass on the tip of the energy harvesting beam component. The proposed small-form-factor design capability was experimentally verified using a fabricated prototype with an occupation volume of 20 × 39 × 6.9 mm³, which was designed for a target frequency of as low as 100 Hz. [ABSTRACT FROM AUTHOR]

Hot pepper is one of the economically important crops in Asia. A large number of gene sequences, including expressed sequence tag (EST) and genomic sequences are publicly available. However, it is still a daunting task to determine gene function due to difficulties in genetic modification of a pepper plants. Here, we show the application of the virus-induced gene silencing (VIGS) repression for the study of 459 pepper ESTs selected as non-host pathogen-induced cell death responsive genes from pepper microarray experiments in Nicotiana benthamiana. Developmental abnormalities in N. benthamiana plants are observed in the 32 (7%) pepper ESTs-silenced plants. Aberrant morphological phenotypes largely comprised of three groups: stunted, abnormal leaf, and dead. In addition, by employing the combination of VIGS and Agrobacterium-mediated transient assays, we identified novel pepper ESTs that involved in Bax or INF1-mediated cell death responses. Silencing of seven pepper ESTs homologs suppressed Bax or INF1-induced cell death, five of which suppressed both cell death responses in N. benthamiana. The genes represented by these five ESTs encode putative proteins with functions in endoplasmic reticulum (ER) stress and lipid signaling. The genes represented by the other two pepper ESTs showing only Bax-mediated cell death inhibition encode a CCCH-type zinc finger protein containing an ankyrin-repeat domain and a probable calcium-binding protein, CML30-like. Taken together, we effectively isolated novel pepper clones that are involved in hypersensitive response (HR)-like cell death using VIGS, and identified silenced clones that have different responses to Bax and INF1 exposure, indicating separate signaling pathways for Bax- and INF1-mediated cell death. [ABSTRACT FROM AUTHOR]

On plants, microbial populations interact with each other and their host through the actions of secreted metabolites. However, the combined action of diverse organisms and their different metabolites on plant health has yet to be fully appreciated. Here, the multifactorial nature of these interactions, at the organismal and molecular level, leading to the biological control of plant diseases is reviewed. To do so, we describe in detail the ecological significance of three different classes of secondary metabolites and discuss how they might contribute to biological control. Specifically, the roles of auxin, acetoin, and phenazines are considered, because they represent very different but important types of secondary metabolites. We also describe how studies of the global regulation of bacterial secondary metabolism have led to the discovery of new genes and phenotypes related to plant health promotion. In conclusion, we describe three avenues for future research that will help to integrate these complex and diverse observations into a more coherent synthesis of bacterially mediated biocontrol of plant diseases. [ABSTRACT FROM AUTHOR]

Using cDNA microarray analysis, we isolated a cDNA clone, CaATL1 ( Capsicum annuum L. Bukang AT-hook-Like gene 1), from a chili pepper plant incompatibly interacting with bacterial pathogens. The deduced amino acid sequence has a potential nuclear localization sequence and an AT-hook DNA binding motif which can bind AT-rich sequence elements. Expression of CaATL1 was specifically induced in host- and non-host-resistant responses against bacterial and viral pathogens in pepper plants. In addition, CaATL1 transcripts also increased following salicylic acid and ethephone treatment but were only mildly induced by methyl-jasmonate treatment. CaATL1::smGFP (soluble-modified green fluorescent protein) fusion protein localized to nuclei in tobacco BY2 protoplasts. The C-terminal region of the CaATL1 protein fused to the LexA DNA binding domain was able to activate reporter gene expression in yeast. To analyse further the role of the CaATL1 in pathogen defence response, we generated CaATL1-over-expressing transgenic tomato plants. These transgenic plants showed enhanced disease resistance against bacterial and oomycete pathogens. Taken together, these results provide the first evidence of a role for a plant AT-hook motif-containing transcription factor in pathogen defence response. [ABSTRACT FROM AUTHOR]

Discusses the generation of mutants of Pseudomonas putida lacking manganese-superoxide dismutase, iron-superoxide dismutase (SOD) or both to investigate the role of superoxide dismutases in root colonization and oxidative stress. Sensitivity of mutants than wild type to oxidative stress; Factors that cause the impaired growth of SOD mutants.

The radial profiles of the electron density at the bottom wall were measured from the center to the edge at argon 3 mTorr with an RF power of 200 W. Since the Boltzmann relation in terms of the fluid picture only describes the behavior of the confined particles, the escaping electrons, which are not confined in plasmas, were not expected to follow the Boltzmann relation. However, unexpected results were observed. The spatial profiles of the density of escaping electrons and the floating potential were well described by the Boltzmann relation with the electron temperature. Moreover, it was concluded that the behavior of the escaping electrons is also described by the generalized Boltzmann relation in terms of the kinetic model. [ABSTRACT FROM AUTHOR]

The radial profiles of the electron density at the bottom wall were measured from the center to the edge at argon 3 mTorr with an RF power of 200 W. Since the Boltzmann relation in terms of the fluid picture only describes the behavior of the confined particles, the escaping electrons, which are not confined in plasmas, were not expected to follow the Boltzmann relation. However, unexpected results were observed. The spatial profiles of the density of escaping electrons and the floating potential were well described by the Boltzmann relation with the electron temperature. Moreover, it was concluded that the behavior of the escaping electrons is also described by the generalized Boltzmann relation in terms of the kinetic model. [ABSTRACT FROM AUTHOR]

The hypersensitive reaction (HR) in plants is typified by a rapid and localized cell death at the site of pathogen infection. To understand better the molecular and cellular defence mechanism controlling HR, hot pepper leaves (Capsicum annuum cv. Pukang) were inoculated with the soybean pustule pathogen Xanthomonas campestris pv. glycine 8ra. By using the DD-PCR technique, a cDNA fragment was identified that exhibited a sequence similarity to the recently identified tobacco pathogen-induced oxygenase (PIOX) with homology to animal cyclo-oxygenase (COX). Subsequently, the full-length cDNA clone, pCa-COX1, encoding the COX homologue from the pathogeninoculated hot pepper leaf cDNA library was isolated. The deduced amino acid sequence of Ca-COX1 shares 85.8% identity with tobacco PIOX and displays a significant degree of sequence identity (21.7-23.7%) with mammalian COXs. The expression of Ca-COX1 was markedly induced at 4-12 h after pathogen infection, while HR cell death on pepper leaves appeared at approximately 15 h post-inoculation. These results are consistent with the notion that the lipid-derived signalling pathway is involved in the initial response of hot pepper plants to pathogen infection. [ABSTRACT FROM AUTHOR]

A novel double-tuned radio-frequency (RF) receiver coil for use in magnetic resonance imaging (MRI) systems has been demonstrated based on a birdcage-type circuit. The receiver coil utilises the endring current as well as the leg current of the birdcage-type circuit to detect the nuclear magnetic resonance (NMR) signals of different elements simultaneously. It was designed to detect the NMR signals of both 1H and 31P elements in a 4.7 T MRI system. The coil showed an excellent frequency response and provided clear magnetic resonance images of a Na2HPO4 phantom when used with the 4.7 T MRI system. [ABSTRACT FROM AUTHOR]

With an enlargement of the wafer size, development of large-area plasma sources and control of plasma density distribution are required. To control the spatial distribution of the plasma density, wireless power transfer is applied to an inductively coupled plasma for the first time. An inner powered antenna and an outer resonant coil connected to a variable capacitor are placed on the top of the chamber. As the self-resonance frequency ?r of the resonant coil is adjusted, the power transfer rate from the inner powered coil to the outer resonant coil is changed and the dramatic evolution of the plasma density profile is measured. As ?r of the outer resonant coil changes from the non-resonant condition (where ?r is not the driving angular frequency ?rf ) to the resonant condition (where ?r = ?rf ), the plasma density profile evolves from a convex shape with maximal plasma density at the radial center into a concave shape with maximal plasma density in the vicinity of the resonant antenna coil. This result shows that the plasma density distribution can be successfully controlled via wireless resonance power transfer. [ABSTRACT FROM AUTHOR]

A new interpolation to estimate a spatial profile of plasma densities of unmeasured regions for two-dimensional probe diagnostics is proposed. Our algorithm is based on the plasma diffusion characteristics. From a comparison with a well known interpolation, Modified Shepard, it has been found that our method gives more accurate plasma density profile, especially at the edge region of the measurement substrate, and improves computational efficiency [ABSTRACT FROM AUTHOR]

A linear turbine cascade experimental apparatus often consists of only a few cascade blades. Advantages to this arrangement are increased from using larger cascade blades and easier optical access. However, fewer cascade blades in the cascade row make it difficult to establish periodic flow conditions between blades. In this study, a 160% pitch passage for cascade experiments with a single blade is designed to satisfy infinite cascade flow conditions without any flow control or tailboards. Fourteen geometric design variables are applied to the design of a 160% pitch passage by using a gradient-based optimization method and a genetic algorithm. Flow structures within a passage designed with a genetic algorithm are closer to the infinite cascade flow conditions than those obtained with a gradient-based method. The results show that infinite cascade flow conditions can be obtained by modifying only the passage walls of the cascade experimental apparatus. [ABSTRACT FROM AUTHOR]

Pseudomonas chlororaphis O6 possesses many beneficial traits involved in biocontrol of plant diseases. In this paper, we examined the effect of a mutation in rpoS encoding a stress-related alternative sigma factor to better understand the regulation of these traits. Biochemical studies indicated that production of acyl homoserine lactones was altered and phenazine was increased in the P. chlororaphis O6 rpoS mutant. The rpoS mutation reduced hydrogen cyanide levels, but the rpoS mutant still displayed a level of in vitro antifungal activity against Fusarium graminearum and Alternaria alternata. Tomato root colonization by the rpoS mutant was lower than that by the wild type at 5, 7, and 13 days after inoculation. The rpoS mutant was less effective than the wild type in induction of systemic resistance to two foliar pathogens after root inoculation of the tomato plants. Our findings demonstrate that the stationary-phase sigma factor RpoS regulates production of several key factors involved in the biocontrol potential of P. chlororaphis O6, some independently of the global regulator GacS. [ABSTRACT FROM AUTHOR]

An optimization study was conducted on a centrifugal compressor. Eight design variables were chosen from the control points for the Bezier curves which widely influenced the geometric variation; four design variables were selected to optimize the flow passage between the hub and the shroud, and other four design variables were used to improve the performance of the impeller blade. As an optimization algorithm, an artificial neural network (ANN) was adopted. Initially, the design of experiments was applied to set up the initial data space of the ANN, which was improved during the optimization process using a genetic algorithm. If a result of the ANN reached a higher level, that result was re-calculated by computational fluid dynamics (CFD) and was applied to develop a new ANN. The prediction difference between the ANN and CFD was consequently less than 1% after the 6th generation. Using this optimization technique, the computational time for the optimization was greatly reduced and the accuracy of the optimization algorithm was increased. The efficiency was improved by 1.4% without losing the pressure ratio, and Pareto-optimal solutions of the efficiency versus the pressure ratio were obtained through the 21st generation. [ABSTRACT FROM AUTHOR]

Bacterial culture filtrates of an aggressive rhizobacterium, Pseudomonas chlororaphis O6, displayed strong nematicidal activity. The nematicidal activity of P. chlororaphis O6 was markedly reduced in the gacS mutant of P. chlororaphis O6 grown in the presence of glycine, but no reduction of nematicidal activity in the gacS mutant was noted in the absence of glycine. The results of bioassay with P. chlororaphis O6 mutants showed that phenazine and pyrrolnitrin production was not a major factor, but the effects of glycine in the culture medium suggest that formation of hydrogen cyanide might be important. Assessments in greenhouse studies with tomatoes growing in nematode-infested soils confirmed that the application of P. chlororaphis O6 resulted in the control of the root-knot nematode. Our results demonstrated that P. chlororaphis O6 could be employed as a biocontrol agent for the control of the root-knot nematode, and the global regulator, GacS, functions as a positive regulator of the expression of nematicidal compounds and enzymes in P. chlororaphis O6. [ABSTRACT FROM AUTHOR]

Previously, root colonization by the rhizobacterium, Pseudomonas chlororaphis O6, was shown to induce expression of galactinol synthase conferring systemic resistance against a fungal pathogen in cucumber leaves. Here, the Arabidopsis – Botrytis cinerea system is introduced to better understand signal transduction of galactinol and (or) raffinose family oligosaccharides (RFO) during O6-mediated induced systemic resistance (ISR). Among the 10 Arabidopsis galactinol synthase genes, only AtGolS1 was specifically induced upon infection with the fungal pathogen B. cinerea. AtGolS1 was primed by O6 colonization against the pathogen in Arabidopsis leaves. Arabidopsis T-DNA insertion mutants at the AtGolS1 gene site compromised O6-mediated ISR against the pathogen, thereby suggesting that AtGolS1 plays an important role in ISR. O6 colonization increased AtGolS1 transcription as well as ISR in several Arabidopsis signaling mutants, but not in the jar1-1 and coi1 mutant lines. Exogenous jasmonate treatment induced transcription of AtGolS1 in wild-type Col-0 plants, but salicylic acid and 1-aminocyclopropane-1-carboxylate did not. These studies on signaling mutants and target gene expression indicate that expression of AtGolS1 in response to O6 colonization is mediated through the jasmonate-dependent pathway, stimulating ISR in Arabidopsis against B. cinerea infection. On a déjà démontré que la colonisation racinaire par la rhizobactérie Pseudomonas chlorographis O6 induit l'expression de la galactinol synthase, conférant une résistance systémique contre un champignon pathogène des feuilles de concombre. Les auteurs introduisent ici le système Arabidopsis – Botrytis cinerea, afin de mieux comprendre la transduction du signal de la famille des oligosaccharides (RFO) galactinol et (ou) raffinose, au cours de la résistance systémique induite (ISR) enclenchée par le O6. Parmi les 10 gènes de la galactinol synthase de l'Arabidopsis, seul le gène AtGolS1 se voit spécifiquement activé suite à une infection par le champignon pathogène B. cinerea. La colonisation par O6 amplifie le gène AtGolS1 contre le pathogène dans les feuilles de l'Arabidopsis. L'insertion du mutant Arabidopsis T-ADN sur le site du gène AtGolS1 compromet l' ISR induit par O6 contre le pathogène, suggérant ainsi que l' AtGolS1 joue un rôle important dans l' ISR. La colonisation par le O6 augmente la transcription du AtGolS1 ainsi que la ISR chez plusieurs mutants signaleurs de l'Arabidopsis, mais n'affecte pas les lignées de mutants jar1-1 et coi1. Un traitement exogène au jasmonate induit la transcription des jar1-1 et coi1 chez les plantes de type sauvage Col-O, mais l'acide salicylique et le 1-aminocyclopropane-1-carboxylate est sans effet. Ces études sur les mutants signaleurs et l'expression du gène cible indiquent que l'expression du AtGolS1, en réaction à la colonisation par le O6, se fait par l'intermédiaire d'un sentier dépendant du jasmonate, en stimulant l' ISR chez l'Arabidopsis contre l'infection par le B. cinerea. [ABSTRACT FROM AUTHOR]

Two extracellular chitinases were purified from Paecilomyces variotii DG-3, a chitinase producer and a nematode egg-parasitic fungus, to homogeneity by DEAE Sephadex A-50 and Sephadex G-100 chromatography. The purified enzymes were a monomer with an apparent molecular mass of 32 kDa (Chi32) and 46 kDa (Chi46), respectively, and showed chitinase activity bands with 0.01% glycol chitin as a substrate after SDS-PAGE. The first 20 and 15 N-terminal amino acid sequences of Chi32 and Chi46 were determined to be Asp-Pro-Typ-Gln-Thr-Asn-Val-Val-Tyr-Thr-Gly-Gln-Asp-Phe-Val-Ser-Pro-Asp-Leu-Phe and Asp-Ala-X-X-Tyr-Arg-Ser-Val-Ala-Tyr-Phe-Val-Asn-Trp-Ala, respectively. Optimal temperature and pH of the Chi32 and Chi46 were found to be both 60°C, and 2.5 and 3.0, respectively. Chi32 was almost inhibited by metal ions Ag+ and Hg2+ while Chi46 by Hg2+ and Pb2+ at a 10 mM concentration but both enzymes were enhanced by 1 mM concentration of Co2+. On analyzing the hydrolyzates of chitin oligomers [(GlcNAc) n, n = 2–6)], it was considered that Chi32 degraded chitin oligomers as an exo-type chitinase while Chi46 as an endo-type chitinase. [ABSTRACT FROM AUTHOR]

Enterobacter intermedium 60-2G, a phosphate solubilizing bacterium, has the ability to induce systemic resistance in plants against soft rot pathogen Erwinia carotovora. Glucose dehydrogenase, an enzyme that utilizes pyrroloquinoline quinone (PQQ) as a cofactor, is required for the synthesis of gluconic acid by E. intermedium 60-2G. Here, we report that the pqqA and pqqB genes are required for phosphate solubilization and induced systemic resistance against a soft rot pathogen in tobacco. Mutations in either the pqqA or pqqB gene abolished the production of 2-ketogluconic acid and eliminated the ability of E. intermedium to solubilize hydroxyapatite. Addition of gluconic acid to the growth media restored the ability of the pqqA mutant to produce 2-ketogluconic acid. Interestingly, both pqqA and pqqB mutants of E. intermedium lost their ability to inhibit the growth of the rice pathogen Magnaporthe grisea KI-409. Additionally, induced systemic resistance against the soft rot pathogen was attenuated in the pqq mutants. These functions were restored by complementation with the wild-type pqq gene cluster. Our findings suggest that PQQ plays an important function in beneficial traits including phosphate solubilization, antifungal activity, and induced systemic resistance of E. intermedium, possibly by acting as a cofactor for several enzymes including glucose dehydrogenase. [ABSTRACT FROM AUTHOR]

TmBa2Cu3O7-x films which is one of the (Rare earth)Ba2Cu3O7-x high temperature superconductors with small ionic radius of rare earth element, were deposited on STO (100) single crystal substrates and Y2O3/YSZ/CeO2 buffered metal substrates by pulsed laser deposition. The Jc (77 K) and the value of onset TC of TmBCO thin film on STO substrate was 4.5 MA/cm2 and 86 K, respectively. The JC of TmBCO coated conductor on metal substrate was 1 MA/cm2. In-field property measurement was carried out at temperatures between 10 K and 77 K in magnetic filed up to 6 T in PPMS system. This is the first report, to the best of our knowledge, of TmBCO thin films and coated conductors with TmBCO film as the superconducting layer which have critical current densities at 77 K of 4.5 MA/cm2 and 1 MA/cm2, respectively. The superconducting properties of TmBCO films and the possibility of using TmBCO film as the superconducting layer of the HTS coated conductor, were investigated. [ABSTRACT FROM AUTHOR]

Phenazine production was engineered in Rhizobium etli USDA9032 by the introduction of the phz locus of Pseudomonas chlororaphis O6. Phenazine-producing R. etli was able to inhibit the growth of Botrytis cinerea and Fusarium oxysporum in vitro. Black bean inoculated with phenazine-producing R. etli produced brownish Fix-nodules. [ABSTRACT FROM AUTHOR]

Colonization of the roots of tobacco by Pseudomonas chlororaphis O6 induces systemic resistance to the soft-rot pathogen, Erwinia carotovora ssp. carotovara SCC1. A screen of the transposon mutants of P. chlororaphis O6 showed mutants with about a fivefold reduction in ability to induce systemic resistance to the soft-rot disease. These mutations disrupted genes involved in diverse functions: a methyl-accepting chemotaxis protein, biosynthesis of purines, phospholipase C, transport of branched-chain amino acids and an ABC transporter. Additional mutations were detected in the intergenic spacer regions between genes encoding a GGDEF protein and fumarate dehydratase, and in genes of unknown function. The mutants in the ABC transporters did not display reduced root colonization. However, the other mutants had up to 100-fold reduced colonization levels. Generally the production of metabolites important for interactions in the rhizosphere, phenazines and siderophores, was not altered by the mutations. A reduced induction of systemic resistance by a purine biosynthesis mutant with a disrupted purM gene correlated with poor growth rate, lesser production of phenazines and siderophore and low levels of root colonization. These studies showed that multiple determinants are involved in the induction of systemic resistance, with there being a requirement for strong root colonization. [ABSTRACT FROM AUTHOR]

Transcription from the dctA gene, which encodes an organic acid transporter in the root-colonizing bacterium Pseudomonas chlororaphis O6, is under complex regulatory control. Promoter sequence analysis revealed an RpoN binding site. The regulation of transcript accumulation by the level of ammonium ions in the growth medium confirmed RpoN regulation, even in the presence of glucose. A dctA mutant colonized tobacco roots to a lesser extent than the wild-type mutant during early seedling development. Colonization by the dctA mutant, as compared to the wild type, also reduced the level of systemically induced resistance against the soft rot pathogen Erwinia carotovora SCC1. We ascribe this reduced colonization to the inability of the mutant to utilize certain organic acid components in the root exudates. The dctA mutant failed to grow on succinate and fumarate, and showed reduced growth on malate. All altered properties of the mutant were complemented by the full-length dctA gene. We propose that organic acids in root exudates may provide important nutrient sources for the beneficial root-colonizing pseudomonad. [ABSTRACT FROM AUTHOR]

The practical application of HTS materials in power devices requires the HTS conductor which is long, powerful (high current carrying), and affordable. Many different methods for making practical coated conductor include multiple ways of obtaining texture templates and a variety of film deposition methods which include both physical and chemical routes. In this work, three film deposition systems (pulsed laser deposition, sputtering, and evaporation) equipped with reel-to-reel metal tape moving apparatus were installed and used to make meter-long coated conductor, Buffer architecture of CeO2/YSZ/Y2O3 was continuously deposited on Ni alloy using sputtering, evaporation, and PLO. YBCO superconducting layer was continuously deposited on buffered metal tape by pulsed laser deposition. End-to-end critical current Ic of 80 A and critical current density Jc of 1.3 MA cm² for 600 nm-thick YBCO at 77 K, self-field have been achieved in 1 cm-wide tape over 1 meter length. Longitudinal distribution of the Ic values was between 72 A/cm and 90 A/cm. [ABSTRACT FROM AUTHOR]

A cDNA library was constructed using mRNA extracted from rice leaves infected with Xanthomonas oryzae pv. oryzae (Xoo), a bacterial leaf blight pathogen, to isolate rice genes induced by Xoo infection. Subtractive hybridization and differential screening of the cDNA library led to the isolation of many induced genes including a nucleotide diphosphate kinase 1 (OsNDPK1) and a pathogenesis-related protein 1 (OsPR1) cDNA. Nucleoside diphosphate kinases (NDPKs) are key metabolic enzymes that maintain the balance between cellular ATP and other nucleoside triphosphates (NTPs). Three other OsNDPK genes (NP922751, OsNDPK2 and OsNDPK3) found in databases were obtained by RTPCR. Three different programs for predicting subcellular targeting indicated that OsNDPK1 and NP922751 were non-organellar, OsNDPK2 plastidic, and OsNDPK3 mitochondrial. Only transcripts of OsNDPK1 accumulated strongly after infection with Xoo. When rice plants were infected with Burkholderia glumae, a bacterial grain/seedling rot pathogen, the pattern of expression of the rice NDPK genes was similar to that following infection with Xoo. OsNDPK1 gene expression was also strongly induced in response to exposure to salicylic acid, jasmonic acid, and abscisic acid, although the level of transcripts and their pattern of expression depended on the inducer. [ABSTRACT FROM AUTHOR]

Chromobacterium sp. strain C-61 is a plant-associated bacterium with proven capacities to suppress plant diseases. Here, we report the draft genome sequence and automatic annotation of strain C-61. A comparison of this sequence to the sequenced genome of Chromobacterium violaceum ATCC 12472 indicates the novelty of C-61 and a subset of gene functions that may be related to its biocontrol activities. [ABSTRACT FROM AUTHOR]

Pseudomonas putida B001 is a rhizobacterium that was isolated on the basis of its abilities to grow under low-nutrient conditions and induce systemic resistance against bacterial, fungal, and viral diseases of plants. Here we report the draft genome sequence and automatic annotation of strain B001. Comparison of this sequence to the sequenced genome of P. putida KT2440 points to a subset of gene functions that may be related to the defense-inducing functions of B001. [ABSTRACT FROM AUTHOR]

Pantoea ananatis B1-9 is an endophytic Gram-negative rhizobacterium that was isolated for its ability to promote plant growth and improve crop yield in the field. Here we report the draft genome sequence of P. ananatis B1-9. Comparison of this sequence to the sequenced genome of a plant-pathogenic P. ananatis strain, LMG20103, indicated that the pathogenesis-related genes were absent, but a subset of gene functions that may be related to its plant growth promotion were present. [ABSTRACT FROM AUTHOR]

Expression of NtNEK2DD, a constitutively active mutant of NtMEK2, activates endogenous salicylic acid-induced protein kinase (SIPK) and wounding-induced protein kinase (WIPK), and leads to several stress/defense responses in tobacco. In this study, we used ACP (annealing control primer)-based differential display reverse transcription–PCR to isolate the downstream effectors mediated by the NtMEK2–SIPK/WIPK cascade. The arginine decarboxylase gene (ADC), which is involved in plant putrescine biosynthesis, was one of nine differentially expressed genes. When compared with NtMEK2KR plants, NtMEK2DD transgenic plants exhibited a significant increase in ADC and ODC (ornithine decarboxylase) transcript levels, as well as in putrescine and its catabolite, γ-aminobutyric acid, following SIPK/WIPK activation. Taken together, these results suggest that the NtMEK2–SIPK/WIPK cascade is involved in regulating polyamine synthesis, especially putrescine synthesis, through transcriptional regulation of the biosynthetic genes in tobacco. [ABSTRACT FROM AUTHOR]