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991.
Mesophyll cells isolated enzymatically from Vigna angularisleaves were fed 14Cglucose or 14C-erythrose and the time-courseof 14C incorporation into shikimic and quinic acids was examined.When 14C-glucose was fed to the cells, the highest radioactivityin quinic acid was observed after 10 hr of incubation, whilethat in shikimic acid was after 14 hr. In the experiment with14C-erythrose, the radioactivity in shikimic acid rose strikinglyup to the 3rd hour, but 14C in quinic acid increased graduallyduring the incubation. The incorporation of 14C into shikimicacid was enhanced when unlabeled shikimic or quinic acid wassupplied to the cells simultaneously with either 14C-glucoseor 14G-erythrose, whereas that into quinic acid was not significantlyincreased by these alicyclic acids. The difference in incorporationrate of 14C into quinic acid from that into shikimic acid wasmore conspicuous in the isolated mesophyll cells than in theepicotyls of V. angularis seedlings.
1 Present address: Department of Biology, Faculty of Science,Kumamoto University, Kumamoto 860, Japan. (Received September 22, 1978; ) 相似文献
992.
Twenty-five terpenoids, 6-phenylacetylenes, 7 phenols, and 15 fatty acids were characterized in this oil. It differs considerably in composition from the oils of A. kurromensis, A. maritima and A. fukudo, which have α- and β-thujone as the major constituents. 相似文献
993.
994.
1H NMR studies on the conformational characteristics of 2-thiopyrimidine nucleotides found in transfer RNAs.
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The molecular conformations of naturally occurring 2-thiopyrimidine nucleosides (5-methylaminomethyl-2-thiouridine, 5-methoxycarbonylmethyl-2-thiouridine and 2-thiocytidine) and 5'-mononucleotides (5-methylaminomethyl-2-thiouridine 5'-monophosphate and 2-thiocytidine 5'-monophosphate) in 2H2O solution were elucidated by analyses of the proton NMR spin-coupling constant, nuclear Overhauser effect, and lanthanide-induced shifts and relaxation enhancements. As monomers, these nucleotides are almost exclusively in the 3E-gg-anti form, even in the absence of ordinary stabilizing factors of this form; i. e., base-stacking and base-pairing interactions with other nucleotide units. This inherent conformational rigidity of the 2-thiopyrimidine units probably contributes to stability of the conformation of tRNA. 相似文献
995.
Dark-grown cells of a mutant strain of Chlorella regularis containedchlorophyll a and protochlorophyll, phytyl ester of protochlorophyllide.Under illumination, protochlorophyll was quantitatively anddirectly converted into chlorophyll a. The photoconversion wasdependent on light intensity and temperature and proceeded ina cell-free preparation. The pathway of chlorophyll formation found in the mutant cellsis entirely different from that from protochlorophyllide byway of chlorophyllide a, which is generally observed in greenplants.
1Present address: Division of Biology, Medical College of Miyazaki,Miyazaki 889-16, Japan.
2Present address: Division of Environmental Biology, The NationalInstitute for Environmental Studies, Ibaragi 300-21, Japan. (Received October 24, 1975; ) 相似文献
996.
ShinIchi Shoji Hiroshi Tsukagoshi Shoko Miyazawa Takashi Hashimoto 《Biochimica et Biophysica Acta (BBA)/General Subjects》1976,428(3):707-710
Triamcinoline acetonide (10 mg per kg of body weight a day) was administered to rabbit fed on a laboratory chow diet. The content of flavins in liver but not in kidney, muscle and brain started to decrease 24 h after a single dose. The activities of enzymes in the liver were determined: the activities of pyruvate dehydrogenase complex, lipoamide dehydrogenase (NADH : lipoamide oxidoreductase EC 1.6.4.3), NADH dehydrogenase (NADH : (acceptor) oxidoreductace EC 1.6.99.3) and
-amino acid oxidase (
-amino acid : oxygen oxidoreductase (deaminating) EC 1.4.3.3) were decreased but those of succinate dehydrogenase (succinate : (acceptor) oxidoreductase EC 1.3.99.1) and xanthine oxidase (xanthine : oxygen oxidoreductase EC 1.2.3.2) remained unchanged. The activities of enzymes in the kidney, however, remained unchanged except the decrease in the activity of pyruvate dehydrogenase complex. 相似文献
997.
998.
Taihei Miyakawa Shoichi Katsuragi Kensho Yamashita Kunio Araki Tetsuo Hashimura Takemi Kimura Kiyoshi Ohuchi 《Virchows Archiv. B, Cell pathology including molecular pathology》1992,61(1):331-335
In this immunohistopathological study α1-antichymotrypsin, which is barely demonstrable in the normal brain, was found in amyloid fibrils, endothelial cells and the
cytoplasm of astroglial cells in brains from patients with Alzheimer’s disease. Amyloid precursors stained with methenamine
silver were arrayed mainly along the membranes, and amyloid fibrils, which stained densely with anti-α1-antichymotrypsin, were in direct contact with the fibrous structures connecting with the membranes of vascular feet or astrocytic
processes.
From the above findings, α1-antichymotrypsin seems to play a role in the production of amyloid fibrils in Alzheimer’s disease. 相似文献
999.
The quantification of phospholipid hydroperoxides in biological tissues is important in order to know the degree of peroxidative damage of membrane lipids. For this purpose, optimal conditions for the chemiluminescent simultaneous assay of phosphatidylcholine hydroperoxide (PCOOH) and phosphatidylethanolamine hydroperoxide (PEOOH) in rat liver and brain were determined. A chemiluminescence detection-high performance liquid chromatography (CL-HPLC) method that incorporates cytochrome c and luminol as a post-column hydroperoxide-specific luminescent reagent was used (Miyazawa et al. 1987. Anal. Lett. 20: 915-925; Miyazawa. 1989. Free Radical Biol. Med. 7: 209-217). An n-propylamine-bound silica column with hexane-2-propanol-methanol-water 5:7:2:1 (v/v/v/v) (flow rate 1.0 ml/min) as eluant was used to determine both PCOOH and PEOOH, which were separated from each other and from other lipids and lipid-soluble antioxidants. High reproducibility and sensitivity as low as 10 pmol hydroperoxide-O2 were observed with a mixture of 10 micrograms/ml cytochrome c and 2 micrograms/ml luminol in 50 mM borate buffer (pH 10.0, flow rate 1.1 ml/min) as luminescent reagent and a post-column mixing joint temperature of 40 degrees C. Using the established analytical conditions, it was confirmed that both PCOOH (1324 +/- 122 pmol/g liver, 114 +/- 18 pmol/g brain, mean +/- SD) and PEOOH (728 +/- 89 pmol/g liver, 349 +/- 60 pmol/g brain, mean +/- SD) are present in the liver and brain of Sprague-Dawley rats bred on a slightly modified AIN-76A semisynthetic diet for 3 months. The phospholipid hydroperoxide content in the rat liver was shown to be affected by dietary oils, but not significantly affected in the brain. 相似文献
1000.
Masuro Shintani Kiyoshi Minaguchi Kazuo Suzuki Kheng-Ann Lim 《Biochemical genetics》1990,28(3-4):173-184
Three new variants of acidic proline-rich proteins (At, Au, Aw) were found in human parotid saliva by isoelectric focusing and basic gel electrophoresis. Electrophoretic comparison of the purified proteins and their tryptic peptides suggested minor charge and size differences from other acidic PRPs. Genetic and biochemical studies indicate that the At and Aw proteins are allelic products of thePRH1 locus. Gene frequencies of the At productive allele (PRH1
6) in Japanese, Chinese, and Malays were 0.008, 0.012, and 0.004, respectively. The Au protein was also found in Japanese (2 in 746 samples), Chinese (1 in 215 samples), and Malays (1 in 220 samples), however, the Aw protein was found only in one Japanese (n=746). These three proteins were not found in 106 Indian subjects.This study was supported in part by a grant from International Scientific Research Program of the Ministry of Education, Science and Culture of Japan, No. 62043071 (representative: K.S.). 相似文献