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991.
Makiko Takagi Saburo Funahashi Keiichi Ohta Toshio Nakabayashi 《Bioscience, biotechnology, and biochemistry》2013,77(12):3019-3020
Attempts to solubilize active ubiquinol: cytochrome c reductase, cytochrome b-c1 complex, from the submitochondrial particles from sweet potato root tissue ended in failure because all detergents tested caused inactivation of this enzyme complex. Consequently, the complex was isolated with the content of cytochrome b as the marker for purification after solubilization with deoxycholate though it was inactive. Deoxycholate had no effect on two ±-bands at 555 and 558 nm but caused a blue shift of an ±-band at 563 nm in the reduced-minus-oxidized difference spectrum of the submitochondrial particles at low temperature. The purified complex exhibited the same difference spectra at low and room temperatures as the submitochondrial particles in the presence of deoxycholate, which suggests that the complex has three (at least two) cytochrome b components with different spectroscopic properties and that the apparent molar ratio of cytochrome b to c1 is 1.5. The purified complex consisted of eight subunits: I, 51 kDa; II, 49kDa; III, 33kDa; IV, 32 kDa; V, 27 kDa; VI, 17 kDa; and VII and VIII, 10 kDa. Subunits III and IV were cytochrome c1 and b, respectively. 相似文献
992.
Yoshiaki Nakagawa Eiichi Kuwano Morifusa Eto Toshio Fujita 《Bioscience, biotechnology, and biochemistry》2013,77(12):3569-3573
The larvicidal activities of benzimidazole derivatives with a terpenoid side chain on the rice stem borer and the silkworm were compared with such in vitro activities as the growth inhibition of the cultured integument of the rice stem borer and the respiration inhibition of rat liver mitochondria. Each larvicidal activity is parallel with these in vitro activities. The comparisons of their activities with those of rotenone and diflubenzuron indicate that the benzimidazoles mainly acted as respiration inhibitors in their larvicidal activity as well as causing cuticular growth inhibition. The activity of 1-(3,7-dimethyl-7-ethoxy-2-octenyl)-2-methylbenzimidazole, the most potent compound tested as a respiration inhibitor, was found to be about 6-fold higher than that of rotenone. In the respiratory chain, the site between NADH and ubiquinone was blocked, indicating that the larvicidal benzimidazoles shared a mode of action with those of rotenone, piericidins, and ubicidines. 相似文献
993.
Akira Fujinami Akihiko Mine Toshio Fujita 《Bioscience, biotechnology, and biochemistry》2013,77(7):1399-1403
Twenty one esters of trans β-(2,4-dichlorophenoxy)acrylic acid were prepared and their inhibitory activity against shoot elongation in the rice plant and barnyard-grass was measured. The relationship between herbicidal activity and chemical structure was analysed using the Hansch approach. The selectivity (activity against barnyard-grass/activity against the rice plant) was mainly due to the lipophilic property of the esters between the two plant species. 相似文献
994.
Chin Piow Wong Jun Deguchi Alfarius Eko Nugroho Toshio Kaneda A. Hamid. A. Hadi Hiroshi Morita 《Bioorganic & medicinal chemistry letters》2013,23(6):1786-1788
In our search for lipid-droplets accumulation (LDA) inhibitors, some ceramicines, a series of limonoids isolated from the barks of Chisocheton ceramicus, were discovered to be active as anti-LDA. Preliminary structure–activity relationships (SAR) of ceramicines as LDA inhibitors based on ceramicines A–L (1–12) and ceramicine B derivatives were described. 相似文献
995.
We elucidated the metabolism of methylglyoxal (MG) in chloroplasts of higher plants. Spinach chloroplasts showed MG-dependent NADPH oxidation because of aldo-keto reductase (AKR) activity. K(m) for MG and V(max) of AKR activity were 6.5 mm and 3.3 μmol NADPH (mg Chl)(-1) h(-1) , respectively. Addition of MG to illuminated chloroplasts induced photochemical quenching (Qp) of Chl fluorescence, indicating that MG stimulated photosynthetic electron transport (PET). Furthermore, MG enhanced the light-dependent uptake of O(2) into chloroplasts. After illumination of chloroplasts, accumulation of H(2) O(2) was observed. K(m) for MG and V(max) of O(2) uptake were about 100 μm and 200 μmol O(2) (mg Chl)(-1) h(-1) , respectively. MG-dependent O(2) uptake was inhibited by 3-(3,4-dichlorophenyl)-1,1-dimethylurea (DCMU) and 2,5-dibromo-3-methyl-6-isopropyl-p-benzoquinone (DBMIB). Under anaerobic conditions, the Qp of Chl fluorescence was suppressed. These results indicate that MG was reduced as a Hill oxidant by the photosystem I (PSI), and that O(2) was reduced to O(2) (-) by the reduced MG. In other words, MG produced in chloroplasts is preferentially reduced by PSI rather than through AKR. This triggers a type of oxidative stress that may be referred to as 'plant diabetes', because it ultimately originates from a common metabolite of the primary pathways of sugar anabolism and catabolism. 相似文献
996.
997.
Yamanaka A Asano M Suzuki M Mizoguchi T Oi T Shimozuru M Tsubota T 《Zoological science》2011,28(2):105-111
We evaluated the stored body fat of Japanese black bears (Ursus thibetanus japonicus) killed as nuisances in Gifu and Fukushima prefectures, Japan, during 2005-2007. We employed femur marrow fat (FMF), modified kidney fat index (mKFI), and abdominal subcutaneous fat (ASF) as indices for quantitative evaluation. We examined the basic characteristics of these indices, such as seasonality, age and sex dependency, and the quantitative relationship among them. mKFI and ASF increased towards the beginning of the denning period (December), while FMF was relatively stable throughout the sampling period (July-December). In cubs, all indices showed significantly lower values than in the older age classes. There seemed to be a catabolizing order between FMF and mKFI, but not between mKFI and ASF. We also evaluated the yearly change in the indices, and discussed its relevance to the incidence of bear intrusion into human residential areas. Bears nuisance-killed in summer (July-September) 2006 had a significantly larger amount of stored body fat than those killed in summer 2007, although the number of nuisance kills was larger in 2006 than in 2007. This suggests that poor nutritional condition is not a direct cause of bear intrusion. 相似文献
998.
He X Takahashi S Suzuki H Hashikawa T Kulkarni AB Mikoshiba K Ohshima T 《Neurochemical research》2011,36(7):1293-1303
Cyclin-dependent kinase 5 (Cdk5) plays a pivotal role in neuronal migration and differentiation, and in axonal elongation.
Although many studies have been conducted to analyze neuronal functions of Cdk5, its kinase activity has also been reported
during oligodendrocyte differentiation, which suggests Cdk5 may play an important role in oligodendrocytes. Here, we describe
a hypomyelination phenotype observed in Emx1-cre mediated Cdk5 conditional knockout (cKO) mice (Emx1-cKO), in which the Cdk5
gene was deleted in neurons, astrocytes and oligodendrocyte -lineage cells. In contrast, the Cdk5 gene in CaMKII cKO mice
was deleted only in neurons. Because the development of mature oligodendrocytes from oligodendrocyte precursor cells is a
complex process, we performed in situ hybridization using markers for the oligodendrocyte precursor cell and for the differentiated
oligodendrocyte. Our results indicate that hypomyelination in Emx1-cKO is due to the impaired differentiation of oligodendrocytes,
rather than to the proliferation or migration of their precursors. The present study confirmed the in vivo role of Cdk5 in
oligodendrocyte differentiation. 相似文献
999.
The enteropathogen Vibrio parahaemolyticus possesses two sets of type III secretion systems, T3SS1 and T3SS2. Effector proteins secreted by these T3SSs are delivered into host cells, leading to cell death or diarrhea. However, it is not known how specific effectors are secreted through a specific T3SS when both T3SSs are expressed within bacteria. One molecule thought to determine secretion specificity is a T3SS-associated chaperone; however, no T3SS2-specific chaperone has been identified. Therefore, we screened T3SS2 chaperone candidates by a pull-down assay using T3SS2 effectors fused with glutathione-S-transferase. A secretion assay revealed that the newly identified cognate chaperone VocC for the T3SS2-specific effector VopC was required for the efficient secretion of the substrate through T3SS2. Further experiments determined the chaperone-binding domain and the amino-terminal secretion signal of the cognate effector. These findings, in addition to the previously identified T3SS1-specific chaperone, VecA, provide a strategy to clarify the specificity of effector secretion through T3SSs of V.?parahaemolyticus. 相似文献