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971.
972.
Ishizaki S Itoh M Komai T Honda T Kitahara T 《Bioscience, biotechnology, and biochemistry》2004,68(5):1164-1166
The main biodegradation product of (+/-)-alpha-isomethylionone (2) with standard activated sludge was characterized as (+/-)-1-(2,6,6-trimethyl-2-cyclohexen-1-yl)propan-2-one (1) by its analysis and synthesis. Both enantiomers (1a and 1b) of 1 were synthesized by starting from (R)- and (S)-2,4,4-trimethyl-2-cyclohexen-1-ol (3a and 3b), respectively. 相似文献
973.
974.
Zhu XuFen Suzuki Kengo Saito Takeshi Okada Kazunori Tanaka Katsunori Nakagawa Tsuyoshi Matsuda Hideyuki Kawamukai Makoto 《Plant molecular biology》1997,35(3):331-341
We have cloned a new geranylgeranyl pyrophosphate (GGPP) synthase gene, designated GGPS6/, from Arabidopsis thaliana genomic DNA. Nucleotide sequence analysis revealed that the GGPS6 gene contains an open reading frame coding for a protein of 343 amino acid residues with a calculated molecular mass of 37 507 Da. Also, the gene is not interrupted by an intron. The predicted amino acid sequence of the GGPS6 gene shows significant homology (34.0–57.7%) with other GGPP synthases from Arabidopsis. The GGPS6 protein contains a N-terminal signal peptide which is thought to function as an organelle targeting sequence. In fact, the GGPS6-GFP fusion protein was found to be localized exclusively in mitochondria when expressed in tobacco BY-2 cells. In vitro analysis of the enzyme activity as well as genetic complementation analysis with Erwinia uredovora crt gene cluster expressed in Escherichia coli showed that the GGPS6 gene most certainly encodes a GGPP synthase catalyzing the conversion of farnesyl pyrophosphate to GGPP. 相似文献
975.
We analysed pigeon flock flights using GPS trajectory data to reveal the most important kinematic aspects of flocking behaviour. We quantitatively investigated the internal motion of the flock based on pairwise statistics and found the following general relationships in all datasets: i) the temporal order of decisions characterised by the delay between directional changes is strictly related to the spatial order characterised by the longitudinal relative position within the flock; ii) during circling motion, pigeons use a mixture of two idealised and fundamentally different turning strategies, namely, parallel-path and equal-radius type turning. While pigeons tend to maintain their relative position within the flock on average, as in the parallel-path approximation, those who turn later also get behind as in the equal-radius case. Equal-radius type turning also tends to be expressed more during smaller radius turns. 相似文献
976.
Takanori Yoshikawa Momoyo Ito Tsuyoshi Sumikura Akira Nakayama Takeshi Nishimura Hidemi Kitano Isomaro Yamaguchi Tomokazu Koshiba Ken‐Ichiro Hibara Yasuo Nagato Jun‐Ichi Itoh 《The Plant journal : for cell and molecular biology》2014,78(6):927-936
Auxin is a fundamental plant hormone and its localization within organs plays pivotal roles in plant growth and development. Analysis of many Arabidopsis mutants that were defective in auxin biosynthesis revealed that the indole‐3‐pyruvic acid (IPA) pathway, catalyzed by the TRYPTOPHAN AMINOTRANSFERASE OF ARABIDOPSIS (TAA) and YUCCA (YUC) families, is the major biosynthetic pathway of indole‐3‐acetic acid (IAA). In contrast, little information is known about the molecular mechanisms of auxin biosynthesis in rice. In this study, we identified a auxin‐related rice mutant, fish bone (fib). FIB encodes an orthologue of TAA genes and loss of FIB function resulted in pleiotropic abnormal phenotypes, such as small leaves with large lamina joint angles, abnormal vascular development, small panicles, abnormal organ identity and defects in root development, together with a reduction in internal IAA levels. Moreover, we found that auxin sensitivity and polar transport activity were altered in the fib mutant. From these results, we suggest that FIB plays a pivotal role in IAA biosynthesis in rice and that auxin biosynthesis, transport and sensitivity are closely interrelated. 相似文献
977.
Kiyoaki Matsubayashi Shunji Gotoh Yoshi Kawamoto Tsuyoshi Watanabe Ken Nozawa Masao Takasaka Toyoko Narita Owen Griffiths Mary-Ann Stanley 《Primates; journal of primatology》1992,33(2):281-288
Clinical inspections were carried out in order to obtain sufficient information concerning the physiological characteristics
and states of natural infection by various pathogenic agents in the population of crab-eating macaques (Macaca fascicularis) on Mauritius. The hematological and plasma biochemical values were within the normal ranges, showing no morbid signs. The
intestinal parasitic appearance was so simplified that onlyStrongyloides andTrichuris were noted as helminthic findings. All of the monkeys examined were free from enteropathogenic organisms such asShigella andSalmonella, and were negative for measles, herpes simplex type 1, simian immunodeficiency virus/MAC, and SV5 antibodies. These data
suggest that the macaques in Mauritius are considerably spared from natural infections by various pathogenic agents.
This study was carried out under the humane conditions prescribed in “The Guidelines for the Study of Wild Primates and Use
of Wild-born Primates” by the Primate Research Institute, Kyoto University, Japan. 相似文献
978.
Tsuyoshi Nishitoba Hiroji Sato Takanori Kasai Hirokazu Kawagishi Sadao Sakamura 《Bioscience, biotechnology, and biochemistry》2013,77(6):1793-1798
Four new bitter terpenoids, lucidenic acids A (1), B (2), C (3) and ganoderic acid C (5), were isolated from the fruiting bodies of Ganoderma lucidum, together with the known bitter ganoderic acid B (4). On the basis of spectroscopic data and chemical conversion, their structures were determined to be 7β-hydroxy-4,4,14α-trimethyl-3,11,15-trioxo-5α-chol-8-en-24-oic acid, 7β,12β-dihydroxy-4,4,14α-trimethyl-3,11,15-trioxo-5α-chol-8-en-24-oic acid, 3β,7β,12β-trihydroxy-4,4,14α-trimethyl-11,15-dioxo-5α-chol-8-en-24-oic acid and 7β-hydroxy-3,11,15,23-tetraoxo-5α-lanost- 8-en-26-oic acid, respectively. 相似文献
979.
Shibata M Lu T Furuya T Degterev A Mizushima N Yoshimori T MacDonald M Yankner B Yuan J 《The Journal of biological chemistry》2006,281(20):14474-14485
Intracellular accumulation of mutant Huntingtin with expanded polyglutamine provides a context-dependent cytotoxicity critical for the pathogenesis of Huntington disease (Everett, C. M., and Wood, N. W. (2004) Brain 127, 2385-2405). Here we demonstrate that the accumulation of mutant Huntingtin is highly sensitive to the expression of beclin 1, a gene essential for autophagy. Moreover, we show that the accumulated mutant Huntingtin recruits Beclin 1 and impairs the Beclin 1-mediated long lived protein turnover. Thus, sequestration of Beclin 1 in the vulnerable neuronal population of Huntington disease patients might further reduce Beclin 1 function and autophagic degradation of mutant Huntingtin. Finally, we demonstrate that the expression of beclin 1 decreases in an age-dependent fashion in human brains. Because beclin 1 gene is haploid insufficient in regulating autophagosome function (Qu, X., Yu, J., Bhagat, G., Furuya, N., Hibshoosh, H., Troxel, A., Rosen, J., Eskelinen, E. L., Mizushima, N., Ohsumi, Y., Cattoretti, G., and Levine, B. (2003) J. Clin. Invest. 112, 1809-1820; Yue, Z., Jin, S., Yang, C., Levine, A. J., and Heintz, N. (2003) Proc. Natl. Acad. Sci. U. S. A. 100, 15077-15082), we propose that the age-dependent decrease of beclin 1 expression may lead to a reduction of autophagic activity during aging, which in turn promotes the accumulation of mutant Htt and the progression of the disease. 相似文献
980.
Xudong Chen Tsuyoshi Fujita Satoshi Ohnishi Minoru Fujii Yong Geng 《Journal of Industrial Ecology》2012,16(1):129-141
Innovative waste recycling through industrial processes such as industrial and urban symbiosis has long been practiced and recently received much attention in the field of industrial ecology, with researchers making efforts to identify key contributing factors to successful industrial symbiosis. By analyzing 88 sample recycling projects in 23 eco‐towns in Japan, this article focuses on the factors of project scale, recycling boundary, and types of waste in relationship to environmental benefits and operational performance. The results showed that larger eco‐towns achieved more savings of virgin materials and higher stability in operation. Large‐scale projects tended to locate closer to the users of recycled products than did small‐scale projects. For treating similar types of waste, projects producing recycled products for special users (e.g., feedstock to a blast furnace for iron production) tended to locate closer to the users than those not producing for special users. The type of waste had a strong effect on the savings of virgin materials and recycling boundaries, while local factors had significant impacts on operational performance. The results also showed that agglomeration did not significantly contribute to the environmental benefits or operational performance of eco‐town projects. Another finding was that national agencies were helpful for facilitating cross‐prefecture transportation and long‐distance transaction of wastes. Implications of the findings are also discussed. 相似文献