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81.
82.
Eiko Matsumura Eiko Yamamoto Atsushi Numata Tatsu Kawano Takashi Shin Sawao Murao 《Bioscience, biotechnology, and biochemistry》2013,77(5):1355-1357
Esters selected from the combination of tricycloalkanecarboxylic acids and some representative pyrethroidal alcohols were prepared, and their insecticidal activities were measured by topical application on housefly, mosquito and German cockroach. Both the exo- and endo-isomers of 2,3-trimethylenenorbornane-2-carboxylic acid exhibited a high level of activity when esterified with m-phenoxymandelonitrile. Piperonyl butoxide showed a strong synergistic effect on some of the esters. Several structural resemblances were found among these active tricyclic acids and the chrysanthemummonocarboxylic acids, which were suggested to be related to insecticidal activity. 相似文献
83.
An alkalopsychrotrophic strain, Micrococcus sp. 207, inducibly and extracellularly produced amylase and pullulanase. The main hydrolysis product from amylose, with a crude enzyme preparation, was maltotetraose. The optimum temperature for activity of the amylase was 60°C and that for pullulanase 55°C. The activities at 0 to 30°C exhibited similar activation energy values. In an optimized production medium at pH 9.7, the highest yields of these enzymes were obtained after cell growth at 18°C for 4 days. At pH 8.5, the yields of amylase and pullulanase became maximum after 3 days cultivation. With more prolonged cultivation, the yield of amylase but not that of pullulanase activity decreased. These enzymes were not produced at temperatures above 30°C. Sucrose was not effective as an inducer, but it stimulated cell growth and enhanced the enzyme productivities with soluble starch. 相似文献
84.
Nobumaro Kawashima Harui Fukushima Ayako Imai Einosuke Tamaki 《Bioscience, biotechnology, and biochemistry》2013,77(9):1141-1145
A leaf protease of tobacco whose activity was enhanced during curing was purified about 60 times with ammonium sulfate fractionation, ethanol precipitation, calcium phosphate gel treatment and Sephadex G-200 column chromatography, and some properties of the protease were examined. The purified enzyme showed the optimum pH at 5.5 and the optimum temperature at 60°C. The protease activity was stable between pH 4.5 and 5.5 at 50°G or at pH 5.5 below 40°C for 1 hr, but completely destroyed at 70°C during 1 hr. The protease activity was greatly activated by reducing agents such as cysteine, glutathione or mercaptoethanol and inhibited by p-chloromercuribenzoate, phenyl- mercuric acetate or silver ions. Metal ions except for silver ion and ethylenediamine tetraacetic acid did not affect the protease activity so far examined. 相似文献
85.
Kazuya Hayashi Danji Fukushima Koya Mogi 《Bioscience, biotechnology, and biochemistry》2013,77(8):988-994
The molecular conformation of the alkaline proteinase of Aspergillus sojae in aqueous solution was investigated by the optical rotatory dispersion, Cotton effects, infra-red absorption spectra (amide I and V bands), ultraviolet difference spectra, etc. It is concluded that; (1) there are about 10 to 15% of the α-helix and a small amount of the β-structure in the enzyme molecule, but most parts of the peptide chain are present as the disordered structure; (2) the enzyme molecule is compactly folded even in the disordered parts; and (3) the two tryptophan residues involved in the peptide chain are burried in the interior of the molecule. 相似文献
86.
Eiko E. Kuramae Erik Verbruggen Remy Hillekens Mattias de Hollander Wilfred F. M. R?ling Marcel G. A. van der Heijden George A. Kowalchuk 《PloS one》2013,8(7)
We assessed soil fungal diversity and community structure at two sampling times (t1 = 47 days and t2 = 104 days of plant age) in pots associated with four maize cultivars, including two genetically modified (GM) cultivars by high-throughput pyrosequencing of the 18S rRNA gene using DNA and RNA templates. We detected no significant differences in soil fungal diversity and community structure associated with different plant cultivars. However, DNA-based analyses yielded lower fungal OTU richness as compared to RNA-based analyses. Clear differences in fungal community structure were also observed in relation to sampling time and the nucleic acid pool targeted (DNA versus RNA). The most abundant soil fungi, as recovered by DNA-based methods, did not necessary represent the most “active” fungi (as recovered via RNA). Interestingly, RNA-derived community compositions at t1 were highly similar to DNA-derived communities at t2, based on presence/absence measures of OTUs. We recovered large proportions of fungal sequences belonging to arbuscular mycorrhizal fungi and Basidiomycota, especially at the RNA level, suggesting that these important and potentially beneficial fungi are not affected by the plant cultivars nor by GM traits (Bt toxin production). Our results suggest that even though DNA- and RNA-derived soil fungal communities can be very different at a given time, RNA composition may have a predictive power of fungal community development through time. 相似文献
87.
88.
Murakami Shinsuke Nakatani Jun Nakajima Kenichi Amasawa Eri Ii Ryota Hayashi Kiyotada Yoshikawa Naoki Daigo Ichiro Kishita Yusuke Ihara Tomohiko Shobatake Koichi Kudoh Yuki Motoshita Masaharu Kanemoto Keiichiro Hara Minako Kashiwagi Aiichiro Hashimoto Seiji Shigetomi Yosuke Kanzaki Masayuki Kikuchi Yasunori Ohno Hajime Fukushima Yasuhiro 《The International Journal of Life Cycle Assessment》2019,24(8):1544-1552
The International Journal of Life Cycle Assessment - 相似文献
89.
Saijou E Itoh T Kim KW Iemura S Natsume T Miyajima A 《The Journal of biological chemistry》2007,282(44):32327-32337
Nucleocytoplasmic translocation constitutes a foundation for nuclear proteins to exert their proper functions and hence for various biological reactions to occur normally in eukaryotic cells. We reported previously that EZI/Zfp467, a 12 zinc finger motif-containing protein, localizes predominantly in the nucleus, yet the underlying mechanism still remains elusive. Here we constructed a series of mutant forms of EZI and examined their subcellular localization. The results delineated a non-canonical nuclear localization signal in the region covering the 9th to the 12th zinc fingers, which was necessary for nuclear accumulation of EZI as well as sufficient to confer nuclear localizing ability to a heterologous protein. We also found that the N-terminal domain of EZI is necessary for its nuclear export, the process of which was not sensitive to the CRM1 inhibitor leptomycin B. An interaction proteomics approach and the following co-immunoprecipitation experiments identified the nuclear import receptor importin-7 as a molecule that associated with EZI and, importantly, short interfering RNA-mediated knockdown of importin-7 expression completely abrogated nuclear accumulation of EZI. Taken together, these results identify EZI as a novel cargo protein for importin-7 and demonstrate a nucleocytoplasmic shuttling mechanism that is mediated by importin-7-dependent nuclear localization and CRM1-independent nuclear export. 相似文献
90.
This study aimed to assess the relationship between basal metabolic rate (BMR) and metabolic heat production, and to clarify the involvement of BMR in determining the phenotype of cold tolerance. Measurements of BMR, maximum oxygen uptake, and cold exposure test were conducted on ten males. In the cold exposure test, rectal (T(rec)) and mean skin temperatures (T(ms)), oxygen uptake, and blood flow at forearm (BF(arm)) were measured during exposure to cold (10 degrees C) for 90 min. Significant correlations were observed between BMR and increasing rate of oxygen uptake, as well as between decreasing rate of BF(arm) and increasing rate of oxygen uptake at the end of cold exposure. These findings suggested that individuals with a lower BMR were required to increase their metabolic heat production during cold exposure, and that those with a higher BMR were able to moderate increased metabolic heat production during cold exposure because they were able to reduce heat loss. This study showed that BMR is an important factor in determining the phenotype of cold tolerance, and that individuals with a low BMR showed calorigenic-type cold adaptation, whereas subjects with a high BMR exhibited adiabatic-type cold adaptation by peripheral vasoconstriction. 相似文献