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991.
Akio Kato Kiyoshi Fujinaga Kazuyoshi Yagishita 《Bioscience, biotechnology, and biochemistry》2013,77(11):2479-2485
Some proteolytic digests of chicken egg white ovomucin were fractionated and characterized. It was shown that there are at least three types of carbohydrate side chains in ovomucin; a chain composed of galactose, galactosamine, sialic acid and sulfate in a molar ratio of about 1: 1: 1: 1, a chain composed of galactose and glucosamine in a molar ratio of about 1:1, and a chain composed of mannose and glucosamine in a molar ratio of about 1:1. It was also shown that the carbohydrate side chain composed of galactose, galactosamine, sialic acid and sulfate is linked O-glycosidically to serine or threonine in the protein core of ovomucin. 相似文献
992.
Galactose oxidase was purified from the culture supernatant of Gibberella fujikuroi by ammonium sulfate precipitation, chromatographies on DEAE-cellulose and hydroxylapatite, and gel filtration on Bio-Gel P-100. The purified enzyme had a molecular weight of 90,000 and an isoelectric point of pH 3.7, and contained about one atom of copper and about one atom of iron per mol of the enzyme protein. The enzyme was markedly inactivated by a copper-chelating agent, diethyldithiocarbamate, and reducing agents. The apoenzyme preparing on treatment of the enzyme with diethyldithiocarbamate could be reactivated only by the addition of either Cu+ or Cu2 +. These results indicate that copper is involved in galactose oxidase activity of G. fujikuroi. 相似文献
993.
Kazuyoshi Yagishita Masaru Nishimura 《Bioscience, biotechnology, and biochemistry》2013,77(11):844-851
Neoilexonol, an unsaponifiable substance first isolated from the barks of Ilex goshiensis Hayata and I. Buergeri Miquel (Aquifoliaceae), has now been proved to be formulated as 11-keto-α-amyrin, i.e., 11-oxours-12-en-3β-ol. 相似文献
994.
Akiho Yokota Atsushi Harada Hirokazu Kobayashi Shozaburo Kitaoka 《Bioscience, biotechnology, and biochemistry》2013,77(8):2045-2052
The half-saturating concentration of ribulose 1,5-bisphosphate carboxylase/oxygenase (RuBisCO) from Euglena gracilis Z for CO2 in its activation by CO2 in the presence of a saturating concentration of MgCl2 (KJ was measured by analyzing the partial reversible inactivation of the fully activated enzyme in the medium with dilute CO2. The Kd of the Euglena enzyme was 12.5 μm. The K,d values were 6.3/im for the enzyme from soybean, 10.8 fiM from maize, 23.3 jiM from Scenedesmus obliquus, and 20.8 μm from Anabaena 7120. The activated state of Euglena RuBisCO was stabilized by 6-phosphogluconate, fructose 1,6-bisphosphate, and 3-phosphoglycerate in the medium containing low concentrations of CO2. Both fructose 6-phosphate and ATP stimulated inactivation in the medium. NADPH not only stabilized the activated state of the enzyme, but also enhanced the enzyme activity over the full activity measured in the absence of NADPH. NADP+ did not nullify the effects of NADPH on the activation at all. The physiological significance of the effects of these photosynthetic metabolites on the activated state of Euglena RuBisCO is discussed. 相似文献
995.
Hajime Ohigashi Kazuyoshi Kawazu Koichi Koshimizu Tetsuo Mitsui 《Bioscience, biotechnology, and biochemistry》2013,77(13):2529-2537
A piscicidal constituent, C32H42O8, was isolated from Sapium japonicum. On the basis of the chemical and spectral studies, the structure of the piscicidal constituent was shown to be 1a, 12-O-n-deca-2,4,6-trienoyl-phorbol-(13)-acetate. 相似文献
996.
Takuo Suzuki Akiko Ishii-Watabe Noritaka Hashii Yukari Nakagawa Tomoko Takahashi Akiko Ebisawa Seiichi Nishi Naho Fujita Aya Bando Yuko Sekimoto Kazuyoshi Miyata Toshio Endo Takuma Otsu Shiori Sugimoto Tadashi Kondou Yuji Fujita Naoyuki Miyanaga Masahiro Mashimo Nana Kawasaki 《Biologicals》2013,41(6):415-423
Heparin is used as an anticoagulant drug. The anticoagulation process is mainly caused by the interaction of heparin with antithrombin followed by inhibition of anticoagulant factor IIa and factor Xa. The anti-factor IIa and anti-factor Xa activities of heparin are critical for its anticoagulant effect; however, physicochemical methods that can reflect these activities have not been established. Thus, the measurements of anti-IIa and anti-Xa activities by biological assay are critical for the quality control of heparin products. Currently in the Japanese Pharmacopoeia (JP), the activities of heparin sodium and heparin calcium are measured by an anti-Xa activity assay (anti-Xa assay), but anti-IIa activity is not measured. Here, we established an anti-IIa activity assay (anti-IIa assay) and an anti-Xa assay having good accuracy and precision. When samples having a relative activity of 0.8, 1.0 and 1.2 were measured by the established anti-IIa and anti-Xa assays in nine laboratories, good accuracy (100.0–102.8% and 101.6–102.8%, respectively), good intermediate precision (1.9–2.1% and 2.4–4.2%, respectively) and good reproducibility (4.0–4.8% and 3.6–6.4%, respectively) were obtained. The established anti-IIa and anti-Xa assays have similar protocols, and could be performed by a single person without a special machine. The established assays would be useful for quality control of heparin. 相似文献
997.
Akio Nakashima Ippei Kawanishi Sumiko Eguchi Eugene Hsin Yu Satoshi Eguchi Noriko Oshiro Ken-ichi Yoshino Ushio Kikkawa Kazuyoshi Yonezawa 《Journal of biomedical science》2013,20(1):24
Background
mTOR is a genetically conserved serine/threonine protein kinase, which controls cell growth, proliferation, and survival. A multifunctional protein CAD, catalyzing the initial three steps in de novo pyrimidine synthesis, is regulated by the phosphorylation reaction with different protein kinases, but the relationship with mTOR protein kinase has not been known.Results
CAD was recovered as a binding protein with mLST8, a component of the mTOR complexes, from HEK293 cells transfected with the FLAG-mLST8 vector. Association of these two proteins was confirmed by the co-immuoprecipitaiton followed by immunoblot analysis of transfected myc-CAD and FLAG-mLST8 as well as that of the endogenous proteins in the cells. Analysis using mutant constructs suggested that CAD has more than one region for the binding with mLST8, and that mLST8 recognizes CAD and mTOR in distinct ways. The CAD enzymatic activity decreased in the cells depleted of amino acids and serum, in which the mTOR activity is suppressed.Conclusion
The results obtained indicate that mLST8 bridges between CAD and mTOR, and plays a role in the signaling mechanism where CAD is regulated in the mTOR pathway through the association with mLST8. 相似文献998.
Keisuke Asada Vonny Salim Sayaka Masada-Atsumi Elizabeth Edmunds Mai Nagatoshi Kazuyoshi Terasaka Hajime Mizukami Vincenzo De Luca 《The Plant cell》2013,25(10):4123-4134
Iridoids form a broad and versatile class of biologically active molecules found in thousands of plant species. In addition to the many hundreds of iridoids occurring in plants, some iridoids, such as secologanin, serve as key building blocks in the biosynthesis of thousands of monoterpene indole alkaloids (MIAs) and many quinoline alkaloids. This study describes the molecular cloning and functional characterization of three iridoid glucosyltransfeases (UDP-SUGAR GLYCOSYLTRANSFERASE6 [UGT6], UGT7, and UGT8) from Madagascar periwinkle (Catharanthus roseus) with remarkably different catalytic efficiencies. Biochemical analyses reveal that UGT8 possessed a high catalytic efficiency toward its exclusive iridoid substrate, 7-deoxyloganetic acid, making it better suited for the biosynthesis of iridoids in periwinkle than the other two iridoid glucosyltransfeases. The role of UGT8 in the fourth to last step in secologanin biosynthesis was confirmed by virus-induced gene silencing in periwinkle plants, which reduced expression of this gene and resulted in a large decline in secologanin and MIA accumulation within silenced plants. Localization studies of UGT8 using a carborundum abrasion method for RNA extraction show that its expression occurs preferentially within periwinkle leaves rather than in epidermal cells, and in situ hybridization studies confirm that UGT8 is preferentially expressed in internal phloem associated parenchyma cells of periwinkle species. 相似文献
999.
1000.
Effect of maternal foraging habitat on offspring quality in the loggerhead sea turtle (Caretta caretta)
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Hideo Hatase Kazuyoshi Omuta Koutarou Itou Teruhisa Komatsu 《Ecology and evolution》2018,8(6):3543-3555
Exploring a trade‐off between quantity and quality of offspring allows differences in the fitness between alternative life histories to be accurately evaluated. We addressed the mechanism that maintains alternative life histories (small oceanic planktivores vs. large neritic benthivores) observed in a loggerhead sea turtle (Caretta caretta) population, which has been suggested to be environmental, based on the lack of genetic structure and a large difference in reproductive output. We examined whether maternal foraging habitat affects offspring quality, by measuring the morphology, emergence success, and righting response of hatchlings following incubation in a common open sand area over the whole nesting season at Yakushima Island, Japan, and by recording early growth and survival of offspring that were reared in a common environment at a Japanese aquarium. Furthermore, we tested whether sea turtles adjust egg size in response to temporal shifts of the incubation environment. There were no significant differences in any hatchling traits between oceanic and neritic foragers (which were classified by stable isotope ratios), except for clutches laid during the warmest period of the nesting season. There were also no significant differences in the growth and survival of offspring originating from the two foragers. The size of eggs from both foragers significantly increased as the season progressed, even though the rookery had heavy rainfall, negating the need to counteract heat‐related reduction in hatchling morphology. In comparison, the sizes of adult body and clutches from both foragers did not vary significantly. The results further support our previous suggestions that the size‐related foraging dichotomy exhibited by adult sea turtles does not have a genetic basis, but derives from phenotypic plasticity. Adjustment in reproductive investment may be associated with: (1) predation avoidance, (2) founder effect, and/or (3) annual variation in egg size. 相似文献