Solid Phase Extraction of Thorium and Uranium and their Separation from Lanthanides using Humic Acid Silica Gel as a Low-Cost Adsorbent

Solid phase extraction and separation of thorium (Th), uranium (U) and lanthanides were achieved using a humic acid-modified silica gel (Si-HA). Adsorption capacity, effect of contact time, pH, and adsorbent dose were examined at room temperature. The maximum adsorbent capacities (pH = 3) for Th and U were 28.0 and 31.3 mg g-1, respectively. The isotherm parameters denoted that the adsorption was favorable and optimum conditions were attained within 90 min. The kinetic data conformed well to pseudo-second order and intra-particle diffusion models. The distribution coefficients of U, Th and lanthanides in EDTA, citric acid and nitric acid media signify the possible separation of each element from the others. The salinity did not significantly affect the ability of Si-HA to extract Th and U. The adsorbent stability and reusability were also assessed through four-adsorption-desorption cycles. The simplicity of the proposed separation method along with the stability of the adsorbent and high regeneration efficiency under acidic conditions demonstrated the merit of using Si-HA as a low-cost adsorbent.

エンドウ原形質膜におけるATPアーゼとホスファチジルイノシトールリン資質リン酸化酵素の共精製

The plasma membrance ATPase was partially purified by a linear glycerol density gradient centrifugation of the detergent-solubilized plasma membrance poteins and subsequent separation by a size-exclusion column chromatogrphy. A purified ATPase preparation is shown to contain a 97.6kDa protein that was cross-reacted with an antibody raised against mung bean H+-ATPase. The preparation also exhibited the phosphorylation of exogenous phosphatidylionsitol(PI) when supplized with [γ-32P]ATP. These results indicate that one form plasma membrance ATPase is co-purified with PI kinase.エンドウの上胚軸組織から分離した原形質膜画分におけるATPアーゼとホスファチジルイノシトールリン脂質リン酸化酵素との相互作用を解析する目的で、双方の原形質膜画分からの可溶化とそれらの部分精製を試みた。原形質膜のTritonX－100可溶化画分をグリセロール連続密度勾配遠心分画に供し、得られた活性画分をさらに分子ふるいカラムクロマトグラフィーによって分離した。この結果、ＡＴＰアーゼとホスファチジルイイノシトールリン脂質リン酸化酵素は共精製され、非変性条件下では双方の活性を分けることができなかった

EFFECT OF SUBSTRATE ON SUSTAINED ARC BETWEEN ELECTRODES

The high voltage generated by solar arrays can cause catastrophic damage such as that from short-circuit due to sustained arcs. Recently, many satellites suffered from sustained arc. The purpose of this paper is to develop the technique of mitigating the sustained arc. Three kinds of substrate were used to investigate the effect of substrate on sustained arc. The experiments were performed in vacuum chamber with an electron beam gun. The polyimide coupon had sustained arc in the condition of 60V and 2A. The ceramic coupon had also sustained arc in 60V and 2A. The coupon without substrate had no sustained arc up to 80V and 3A. We found that no sustained arc could occur without substrate between cells on this condition.The 25th International Symposium on Space Technology and Science (25th ISTS) June 4-11, 2006, Kanazawa City, Ishikawa, Japa

Solid Phase Extraction of Thorium and Uranium and their Separation from Lanthanides using Humic Acid Silica Gel as a Low-Cost Adsorbent

Solid phase extraction and separation of thorium (Th), uranium (U) and lanthanides were achieved using a humic acid-modified silica gel (Si-HA). Adsorption capacity, effect of contact time, pH, and adsorbent dose were examined at room temperature. The maximum adsorbent capacities (pH = 3) for Th and U were 28.0 and 31.3 mg g-1, respectively. The isotherm parameters denoted that the adsorption was favorable and optimum conditions were attained within 90 min. The kinetic data conformed well to pseudo-second order and intra-particle diffusion models. The distribution coefficients of U, Th and lanthanides in EDTA, citric acid and nitric acid media signify the possible separation of each element from the others. The salinity did not significantly affect the ability of Si-HA to extract Th and U. The adsorbent stability and reusability were also assessed through four-adsorption-desorption cycles. The simplicity of the proposed separation method along with the stability of the adsorbent and high regeneration efficiency under acidic conditions demonstrated the merit of using Si-HA as a low-cost adsorbent

A Volatile Substance, β-Caryophyllene, from Talaromyces wortmannii Promotes Growth and Tolerance to Diseases on Several Plants

A plant growth-promoting fungus, Talaromyces wortmannii strain FS2 was isolated from an agricultural field at Okayama Pref. FS2 enhanced seed germination, root elongation and leaf growth of Brassica rapa var perviridis (Komatsuna). Such plant growth-promoting effect was observed in the same sealed chamber where FS2 was cultured on PDA medium separated from seedlings, suggesting effective volatile compound(s). GC‒MS analysis showed that FS2 emitted at least seven terpenoids, of which a volatile was identified as β‒caryophyllene. β‒caryophyllene alone promoted the growth of cucumber, Nicotiana benthamiana and barley. Furthermore β‒caryophyllene increased the yield of cucumber fruits. Interestingly, we found that β‒caryophyllene conditioned these plants to be resistant to respective diseases caused by Colletotrichum orbiculare, Botrytis cinerea or Blumeria graminis f. sp hordei. The findings indicate that β‒caryophyllene has desirable dual features and therefore, it is available to cultivation of many crops.岡山県総社市の圃場から分離した植物生育促進菌Talaromyces wortmannii FS2が生産するβ-caryophylleneは，コマツナ（アブラナ科）のみならず，キュウリ（ウリ科），タバコ（ナス科）およびオオムギ（イネ科）など広汎な植物に対して，生育促進作用および耐病性増進作用を示したことから，有用な農業資材として利用可能であるものと考察した

病原菌シグナルによるエンドウ原形質膜におけるホスファチジルイノシトールリン脂質のリン酸化とリゾリン脂質生成の制御

Effects of elicitor and suppressor from a pea pathogen, Mycosphaerella pinodes, on Pl etabolism in pea plasma membrane were examined in vitro. The elicitor induced rapid phosphorylation of phosphatidylinositols as well as production of lysophospholipid in plasma membranes, but these responses were severely inhibited by the suppressor. These results indicate that a membrane-associated phospholipase A is regulated coordinately by fungal signals, together with Pl metabolism, and that it may participate in signal transduction pathways leading to defense responses. To evaluate a possible rote of phospholipase A activation in induction of a pea defense response, the effect of free fatty acid on induction of a phytoalexin accumulation was also examined. When pea leaves were treated with linoleic- or linolenic acid, most commonly released in plant cells by phospholipase A, the accumulation of pisatin was induced even in the absence of the elicitor. It is, therefore, conceivable that free fatty acid(s) released from plasma membrane is also implicated in the early stage of elicitor-signal transduction in pea.エンドウの上胚軸組織により分離した原形質膜画分を褐紋病菌の生産するエリシターで処理すると、ホスファチジルイノシトールリン脂質の急速なリン酸化とリゾリン脂質の生成が誘導されたが、同菌より調製したサプレッサーの共存下では双方とも著しく阻害された。本結果は、ポリホスホイノシチド代謝系と同調的に作動するホリパーゼA活性化が存在すること、さらに、原形質膜における病原菌シグナルの受容・応答には複数の資質代謝系が介在する可能性を示唆している。一方、ホスホリパーゼAの活性化の役割を調べる目的で、本酵素によって原形質膜から生成されると考えられる脂肪酸(リノール酸ならびにリノレン酸)をエンドウ葉に処理したところ、エリシターの非存在下においてもファイトアレキシンであるピサチンの生成が誘導されることが示された。以上から、ポリホスホイノシチド代謝系と同調的に働くホスホリパーゼAがエリシターシグナルの初期伝達に深く関連しているものと考えられた

Quorum-dependent expression of rsmX and rsmY, small non-coding RNAs, in Pseudomonas syringae

Pseudomonas syringae pathovars are known to produce N-acyl-homoserine lactones (AHL) as quorum-sensing molecules. However, many isolates, including P. syringae pv. tomato DC3000 (PtoDC3000), do not produce them. In P. syringae, psyI, which encodes an AHL synthase, and psyR, which encodes the transcription factor PsyR required for activation of psyI, are convergently transcribed. In P. amygdali pv. tabaci 6605 (Pta6605), there is one nucleotide between the stop codons of both psyI and psyR. However, the canonical stop codon for psyI in PtoDC3000 was converted to the cysteine codon by one nucleotide deletion, and 23 additional amino acids extended it to a C-terminal end. This resulted in overlapping of the open reading frame (ORF) for psyI and psyR. On the other hand, stop codons in the psyR ORF of P. syringae 7 isolates, including pv. phaseolicola and pv. glycinea, were found. These results indicate that many pathovars of P. syringae have genetically lost AHL production ability by the mutation of their responsible genes. To examine whether PtoDC3000 modulates the gene expression profile in a population-dependent manner, we carried out microarray analysis using RNAs prepared from low- and high-density cells. We found the expressions of rsmX and rsmY remarkably activated in high-density cells. The activated expressions of rsmX and rsmY were confirmed by Northern blot hybridization, but these expressions were abolished in a ΔgacA mutant of Pta6605. These results indicate that regardless of the ability to produce AHL, P. syringae regulates expression of the small noncoding RNAs rsmX/Y by currently unknown quorum-sensing molecules

Requirement of γ-Aminobutyric Acid Chemotaxis for Virulence of Pseudomonas syringae pv. tabaci 6605

γ-Aminobutyric acid (GABA) is a widely distributed non-proteinogenic amino acid that accumulates in plants under biotic and abiotic stress conditions. Recent studies suggested that GABA also functions as an intracellular signaling molecule in plants and in signals mediating interactions between plants and phytopathogenic bacteria. However, the molecular mechanisms underlying GABA responses to bacterial pathogens remain unknown. In the present study, a GABA receptor, named McpG, was conserved in the highly motile plant-pathogenic bacteria Pseudomonas syringae pv. tabaci 6605 (Pta6605). We generated a deletion mutant of McpG to further investigate its involvement in GABA chemotaxis using quantitative capillary and qualitative plate assays. The wild-type strain of Pta6605 was attracted to GABA, while the ΔmcpG mutant abolished chemotaxis to 10‍ ‍mM GABA. However, ΔmcpG retained chemotaxis to proteinogenic amino acids and succinic semialdehyde, a structural analog of GABA. Furthermore, ΔmcpG was unable to effectively induce disease on host tobacco plants in three plant inoculation assays: flood, dip, and infiltration inoculations. These results revealed that the GABA sensing of Pta6605 is important for the interaction of Pta6605 with its host tobacco plant

ĐÁNH GIÁ KHẢ NĂNG PHÒNG TRỪ SINH HỌC BỆNH THÁN THƯ (COLLETOTRICHUM OBICULARE 104T) TRÊN CÂY DƯA LEO (CUCUMIS SATIVUS CV. TSUYATARO) CỦA MỘT SỐ DÒNG ACTINOMYCETES NỘI SINH

Đề tài được thực hiện nhằm đánh giá khả năng chống chịu với một số điều kiện stress, khả năng phòng trừ bệnh thán thư (Colletotrichum orbiculare) trên cây dưa leo và khảo sát sự biểu hiện của các gene liên quan đến sự hình thành bệnh (Yoshida, 2009). Ba dòng nấm được đánh giá ở các chế độ nhiệt độ (23, 30, 35 và 40oC), trong môi trường bổ sung NaCl (0,5 và 1M) và pH (4 và 8). Khả năng kiểm soát sinh học của ba dòng Actinomyces được đánh giá bằng cách nhỏ giọt dịch chứa C. orbiculare lên bề mặt của lá thật của cây con xử lý trước với Actnomycetes. Kết quả cho thấy hai dòng A12 và A19 có thể đáp ứng tốt với nhiệt độ 35 và 40oC. Dòng A12 và A16 đáp ứng tốt với nghiệm thức bổ sung 1M NaCl. Cả ba dòng có thể sinh trưởng tốt ở mức pH 4 và 8. Trong số ba dòng được đánh giá, A12 cho thấy khả năng phòng trị hiệu quả, làm giảm rõ rệt (p< 0.01) số lượng và diện tích vết bệnh so với đối chứng. Dòng A12 ở mức OD660=2 cho kết quả phòng trị tốt nhất. Kết quả biểu hiện gene liên quan đến sự gây bệnh cho thấy lá thật xử lý với dòng A12 có mức biểu hiện gen PAL cao hơn so với đối chứng và các dòng khác

逆転写酵素・DNAポリメラーゼを用いたRT-PCRによる増幅反応で確認されたペッパーマイルドモットルウイルス（PMMoV）感染ピーマンの果実種子におけるウイルスの効果的な不活性化方法

A method for efficient inactivation Papper mild mottle virus (PMMoV) in harvested seeds of green pepper was examined based on the infectivity on the leaves of Nicotina glutinosa L.(a local host) and a reverse transcription and polymerase chain reaction (RT-PCR)-based amplification of the viral RNA. The seed homogenates from PMMoV-infected plants produced a large number of necrotic local lesion in N.glutinosa, but soaking the seeds in 10% (w/v) tri-sodium phosphate (Na3PO4) for 20 min or dry sterilization (70C,3h) effectivity eliminated the abundance of PMMoV. However, no necrotic lesion on N.glutinosa or the RT-PCR-basaed amplification was observed with seeds that has been disinfected by Na3PO4 in combination with dry sterilization