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151.
Effect of Bacillus thuringiensis Cry1 Toxins in Insect Hemolymph and Their Neurotoxicity in Brain Cells of Lymantria dispar 下载免费PDF全文
Anja Cerstiaens Peter Verleyen Jeroen Van Rie Emmy Van Kerkhove Jean-Louis Schwartz Raynald Laprade Arnold De Loof Liliane Schoofs 《Applied microbiology》2001,67(9):3923-3927
Little information is available on the systemic effects of Bacillus thuringiensis toxins in the hemocoel of insects. In order to test whether B. thuringiensis-activated toxins elicit a toxic response in the hemocoel, we measured the effect of intrahemocoelic injections of several Cry1 toxins on the food intake, growth, and survival of Lymantria dispar (Lepidoptera) and Neobellieria bullata (Diptera) larvae. Injection of Cry1C was highly toxic to the Lymantria larvae and resulted in the complete inhibition of food intake, growth arrest, and death in a dose-dependent manner. Cry1Aa and Cry1Ab (5 μg/0.2 g [fresh weight] [g fresh wt]) also affected growth and food intake but were less toxic than Cry1C (0.5 μg/0.2 g fresh wt). Cry1E and Cry1Ac (5 μg/0.2 g fresh wt) had no toxic effect upon injection. Cry1C was also highly toxic to N. bullata larvae upon injection. Injection of 5 μg/0.2 g fresh wt resulted in rapid paralysis, followed by hemocytic melanization and death. Lower concentrations delayed pupariation or gave rise to malformation of the puparium. Finally, Cry1C was toxic to brain cells of Lymantria in vitro. The addition of Cry1C (20 μg/ml) to primary cultures of Lymantria brain cells resulted in rapid lysis of the cultured neurons. 相似文献
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The CO2 fixation system, that is formic acid production from CO2 with FDH from Saccharomyces cerevisiae and reduced Methyl viologen produced by the visible light photosensitization of zinc tetrakis(4-methylpyridyl) porphyrin, was investigated. When the sample solution containing triethanolamine, zinc tetrakis(4-methylpyridyl) porphyrin, Methyl viologen, NaHCO3 and FDH in phosphate buffer was irradiated, formic acid was produced. The amount of formic acid production and the yield of CO2 to formic acid were estimated to be 0.104 ± 0.008 mM and 10.4%, respectively. 相似文献
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Daisuke Takamatsu Rie Arai Tohru Miyoshi-Akiyama Kayo Okumura Masatoshi Okura Teruo Kirikae Atsuko Kojima Makoto Osaki 《Applied and environmental microbiology》2013,79(12):3882-3886
Melissococcus plutonius is a fastidious honeybee pathogen, and the addition of KH2PO4 to culture medium is required for its growth. Using genome sequences and a newly developed vector, we showed that mutations in genes encoding Na+/H+ antiporter and cation-transporting ATPase are involved in the potassium requirement for growth. 相似文献
156.
Melissa Carrillo Suraj Pandey Juan Sanchez Moraima Noda Ishwor Poudyal Luis Aldama Tek Narsingh Malla Elin Claesson Weixiao Yuan Wahlgren Denisse Feliz Vukica Šrajer Michał Maj Leticia Castillon So Iwata Eriko Nango Rie Tanaka Tomoyuki Tanaka Luo Fangjia Marius Schmidt 《Structure (London, England : 1993)》2021,29(7):743-754.e4
157.
The second (index finger) to fourth (ring finger) digit length ratio (2D:4D) is known to be a putative marker of prenatal exposure to testosterone. It has been reported that fetal and adult testosterone may be critical for development of physical and mental traits such as cardiovascular system, reaction time, aggressiveness and masculinity. Testosterone-driven attributes are associated with success in male-to-male physical competition, which may be proxied by ability in sports. Many researchers have found that 2D:4D is sexually dimorphic and is a negative correlate of athletic performance. This study aims to investigate the associations of 2D:4D with measures of power as another possible testosterone-associated trait using ability in sumo wrestling as a proxy for male physical competitiveness. The measures of sumo performance comprised the sumo ranks and winning percentages of 142 Japanese professional sumo wrestlers. We found that sumo wrestlers with low 2D:4D had higher sumo ranks and better winning records. The significant negative associations between 2D:4D and the athletic prowess of sumo wrestlers provide further evidence of the possible link between high testosterone levels and muscle strength. The relatively small effect sizes found in this study, however, imply that 2D:4D may be a weaker predictor for sports requiring explosive power than for those requiring endurance. 相似文献
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Kota Nakatani Yuta Katano Kenji Kojima Teisuke Takita Rie Yatsunami Satoshi Nakamura 《Bioscience, biotechnology, and biochemistry》2018,82(10):1715-1723
Site saturation mutagenesis library is a recently developed technique, in which any one out of all amino acid residues in a target region is substituted into other 19 amino acid residues. In this study, we used this technique to increase the thermostability of a GH10 xylanase, XynR, from Bacillus sp. strain TAR-1. We hypothesized that the substrate binding region of XynR is flexible, and that the thermostability of XynR will increase if the flexibility of the substrate binding region is decreased without impairing the substrate binding ability. Site saturation mutagenesis libraries of amino acid residues Tyr43–Lys115 and Ala300–Asn325 of XynR were constructed. By screening 480 clones, S92E was selected as the most thermostable one, exhibiting the residual activity of 80% after heat treatment at 80°C for 15 min in the hydrolysis of Remazol Brilliant Blue-xylan. Our results suggest that this strategy is effective for stabilization of GH10 xylanase.
Abbreviations: DNS: 3,5-dinitrosalicylic acid; RBB-xylan: Remazol Brilliant Blue-xylan 相似文献
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