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671.
Tomoyoshi Iwatsubo Hiroki Nakagawa Nagao Ogura Hidetaro Takehana 《Bioscience, biotechnology, and biochemistry》2013,77(4):907-908
Optically active trisubstituted and tetrasubstituted cyclopentanes, with proper functional groups of proper stereochemistry as precursors for chiral synthesis of brefeldin A and prostaglandins, were prepared stereoselectively from carbohydrate. 相似文献
672.
Ken-ichiro Taoka Zenpei Shimatani Koji Yamaguchi Mana Ogawa Hiromi Saitoh Yoichi Ikeda Hiroko Akashi Rie Terada Tsutomu Kawasaki Hiroyuki Tsuji 《Plant Biotechnology》2021,38(1):89
Luciferases have been widely utilized as sensitive reporters to monitor gene expression and protein-protein interactions. Compared to firefly luciferase (Fluc), a recently developed luciferase, Nanoluciferase (NanoLuc or Nluc), has several superior properties such as a smaller size and stronger luminescence activity. We compared the reporter properties of Nluc and Fluc in rice (Oryza sativa). In both plant-based two-hybrid and split luc complementation (SLC) assays, Nluc activity was detected with higher sensitivity and specificity than that with Fluc. To apply Nluc to research involving the photoperiodic regulation of flowering, we made a knock-in rice plant in which the Nluc coding region was inserted in-frame with the OsMADS15 gene, a target of the rice florigen Hd3a. Strong Nluc activity in response to Hd3a, and in response to change in day length, was detected in rice protoplasts and in a single shoot apical meristem, respectively. Our results indicate that Nluc assay systems will be powerful tools to monitor gene expression and protein-protein interaction in plant research. 相似文献
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674.
We analyzed the binding of heparinoid or heparin with fibrinogen by real-time measurement using surface plasmon resonance technology. Poly(glucosyloxyethyl methacrylate) sulfate [poly(GEMA) sulfate] and dextran sulfate were used as heparinoids. The binding ability of each sulfated polymer was estimated by having each polymer-containing buffer interact with the sensor chip surfaces that had immobilized fibrinogen. Dextran sulfate and poly(GEMA) sulfate showed high affinity to the fibrinogen in this experiment, while the heparin did not. All of the dextran sulfates were desorbed from its surface, while about 30% of the poly(GEMA) sulfate remained on the immobilized fibrinogen upon the addition of NaCl to the buffer which was done in order to analyze the desorption of poly(GEMA) sulfate or dextran sulfate from the surface of the fibrinogen. These data show that the type of binding between fibrinogen-poly(GEMA) sulfate was different from that of dextran sulfate, indicating that the interaction between fibrinogen and poly(GEMA) sulfate was caused not only by an electrostatic but also by a hydrophobic force. These results suggest that the interaction mechanism of heparinoids with fibrinogen was different from that of heparin. 相似文献
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676.
Snow cover manipulation in agricultural fields: as an option for mitigating greenhouse gas emissions
Yosuke Yanai Tomoyoshi Hirota Yukiyoshi Iwata Manabu Nemoto Nobuhisa Koga Osamu Nagata Shinjiro Ohkubo 《Ecological Research》2014,29(4):535-545
Short-term N2O emission occurs in relation to snowmelt within seasonally frozen soil. To understand the effects of changing winter climates on the N2O flux, snow cover manipulation experiments are useful. In Japan, snow cover manipulation is practiced by farmers to improve agricultural yield and is executed either by applying a broadcast of blackish agent onto the snow cover, which leads to faster snow-melting thereby extending the crop-growing season, or by snow cover removal/re-accumulation, leading to an enhanced soil frost depth for weed management. Implementation of these practices involves using an amount of fossil fuel, in addition to influencing soil-derived N2O emissions, therefore, the load factors of snow cover management practices per unit area of agricultural field were estimated in this study. Field data including micrometeorological conditions, ground surface flux of N2O, and amount of fossil fuel consumed during machinery operation for management practices, were obtained at two sites in Hokkaido over 2 years (2008–2010). Fuel consumption for the field spreading was found to be unexpectedly small (0.017 Mg CO2 eq ha?1). It was therefore suggested that acceleration of snowmelt may have the potential to reduce net greenhouse gas emissions if the agent used is a low-degradable C-rich material, such as charcoal. For soil frost control, the fossil fuel consumption during a set of snow cover removal/re-accumulation (estimated as 0.052 Mg CO2 eq ha?1) is discussed, together with the relationship between possible mechanisms causing stimulation of N2O production in frozen soil and inherent large differences in N2O flux among sites. 相似文献
677.
Similarity of kinetics of three types of myeloperoxidase from human leukocytes and four types from HL-60 cells 总被引:3,自引:0,他引:3
Km values for H2O2 and Vmax values for three types of myeloperoxidase (MPO) from human leukocytes (MPO-I, -II, and -III) and four types from human myeloid leukemia HL-60 cells (MPO-IA, -IB, -II, and -III) were determined. Km values of human leukocyte MPOs decreased with increasing pH from 4.4 to 6.2 and increased with increasing NaCl concentration from 0.025 to 0.14 M. There was no significant difference among Km values of leukocyte MPO-I, -II, and -III. NaBr also showed a tendency similar to that of NaCl with regard to the effects of pH and halide concentration on Km values. However, Km values in the presence of NaBr were lower than those in the presence of NaCl. Effects of pH and NaCl concentration on Vmax values of MPO-I, -II, and -III were also examined. Vmax values of MPO-I, -II, and -III were higher at pH 4.9 and 5.4 and increased with increasing NaCl concentration. In addition, no difference was observed between Km values of leukocyte and those of HL-60 cells. MPO-IB, the half-molecular-weight enzyme of HL-60 cells, also had the same Km values as the others. Furthermore, inhibition of the activities of seven MPOs of leukocytes and HL-60 cells by H2O2 was similarly observed at concentrations above 1 mM at pH 5.4 but not at pH 4.4. These results indicate that there is no difference in the affinity to H2O2 among leukocyte MPO-I, -II, and -III and HL-60 cell MPO-IA, -IB, -II, and -III. 相似文献
678.
Hiroya Yurimoto Hiroyuki Iguchi Do Thi Di Thien Akio Tani Yutaka Okumoto Atsushi Ota Takahiro Yamauchi Takahiro Akashi Yasuyoshi Sakai 《Microbial biotechnology》2021,14(4):1385-1396
Methylotrophs, which can utilize methanol as a sole carbon source, are promising microorganisms to be exploited in a methanol-based bioeconomy, in which a variety of useful compounds are biotechnologically produced from natural gas-derived methanol. Pink-pigmented facultative methylotrophs (PPFMs) are common plant phyllospheric bacteria and are known to enhance seedling growth and total biomass of various plants. However, improvement of crop yield by inoculation of PPFMs at the field level has not been well investigated. We herein describe improvement of crop yield of several rice cultivars by foliar spraying of PPFMs. After selection of PPFM strains and rice cultivars by the in vitro seedling growth test, we further conducted paddy field experiments. The crop yield of the sake-brewing rice Oryza sativa cultivar Hakutsurunishiki was reproducibly improved in a commercial paddy field for over a 5-year period. A one-time foliar spray of PPFM cells (living or killed) or a cell wall polysaccharide fraction, after the heading date, acted in the phyllosphere and effectively improved crop yield. Our results show that the established process with PPFMs is feasible for improvement of food production in the methanol bioeconomy. 相似文献
679.
Terada Tomoyoshi Morisaka Tadamichi Wakabayashi Ikuo Yoshioka Motoi 《Journal of Ethology》2022,40(3):245-256
Journal of Ethology - Toothed whales are the ideal model to validate the hypothesis that the complexity of sound communication relates to sociality. Compared to the numerous studies on several... 相似文献
680.