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1.
Saito On Kobayashi Tatsuya Hiroi Maiko Kawatsu Masayuki Takagi Shun Nishihiro Jun Kagami Maiko 《Limnology》2019,20(1):21-28
Limnology - Trapa spp. dominate many shallow eutrophic lakes in Japan, which must affect the nutrient dynamics in lakes. Trapa spp. are utilized by several animals, in particular the leaf beetle,... 相似文献
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Tsutomu Yamaguchi Norihiro Tsukakoshi Gakuzo Tamura Kei Arima 《Bioscience, biotechnology, and biochemistry》2013,77(4):475-480
The components of fractions obtained by dialyzing and differential centrifuging the “Ghost” of Bacillus megaterium were analyzed in detail. The compositions of amino acids in the main fractions (Fraction 2 and 3) of the “Ghosts”, were estimated. Fraction 2 was rich in non-polar amino acids, while Fraction 3 was scanty of them. Most of the fatty acids in Fraction 2 were 12-methyl tetradecanoic acid, while in Fraction 3 many kinds of fatty acid were detected.As for the localization of enzymes, the three enzymes, glucose oxidase, succinic dehydrogenase and reduced nicotinamide-adenine dinucleotide oxidase, which were present in the original “Ghosts”, were mostly observed in Fraction 2, and a very little amount of them was found in the other fractions. Further, Fraction 2 could be dissolved in formic acid and dialysis of the solution brought about reaggregation to form membrane-like structure in the presence of Ca or Mg ion. 相似文献
5.
Kazuhiro Haraguchi Shigeru Saito Hiromichi Tanaka Tadashi Miyasaka 《Nucleosides, nucleotides & nucleic acids》2013,32(2-4):483-493
Abstract Pummerer-type rearrangement of uracil nucleosides having a phenylseleno group in the 2′-, 3′-, and 5′-positions took place upon oxidation with MCPBA in CH2Cl2 followed by treatment with acid anhydrides to yield α-acyloxyselenides. 相似文献
6.
A Ajima S G Cao K Takahashi A Matsushima Y Saito Y Inada 《Biotechnology and applied biochemistry》1987,9(1):53-57
Hemin, having two carboxyl groups, was coupled with alpha-(3-aminopropyl)-omega-methoxypoly(oxyethylene) through the acid-amide bond formed with carbodiimide. The modified hemin catalyzed the peroxidase reaction in 1,1,1-trichloroethane using benzoyl peroxide or peroxides in unsaturated fatty acids as the hydrogen acceptor and leuco crystal violet as the hydrogen donor. A basic study on quantitative microanalysis of the lipid peroxides was attempted. 相似文献
7.
Lipid composition of PC12 pheochromocytoma cells: characterization of globoside as a major neutral glycolipid 总被引:4,自引:0,他引:4
T Ariga L J Macala M Saito R K Margolis L A Greene R U Margolis R K Yu 《Biochemistry》1988,27(1):52-58
We have studied the lipid composition of PC12 pheochromocytoma cells cultured in the presence and absence of nerve growth factor (NGF). Neutral and acidic lipid fractions were isolated by column chromatography on DEAE-Sephadex and analyzed by high-performance thin-layer chromatography (HPTLC). The total lipid concentration was approximately 220 micrograms/mg of protein, and the concentration of neutral glycolipids was 1.6-1.8 microgram/mg of protein for both NGF-treated and untreated cells. The neutral glycolipid fraction contained a major component, which accounted for approximately 80% of the total and which was characterized as globoside on the basis of HPTLC mobility, carbohydrate analysis, fast atom bombardment mass spectrometry, and mild acid hydrolysis. The major fatty acids of globoside were C16:0 (10%), C18:0 (16%), C22:0 (23%), C24:1 (17%), and C24:0 (24%). C18 sphingenine accounted for almost all of the long-chain bases. The other neutral glycolipids were tentatively identified as glucosylceramide (15%), lactosylceramide (4%), and globotriosylceramide (4.5%). The concentration of ganglioside sialic acid was approximately 0.34 and 0.18 microgram/mg of protein for cells grown in the presence and absence of NGF, respectively. Although there was an increase in ganglioside concentration in NGF-treated cells, NGF did not produce any differential effects on the relative proportions of the individual gangliosides. Several of the gangliosides appear to contain fucose, and one of these was tentatively identified as fucosyl-GM1. Brain-type gangliosides of the ganglio series were also detected by an HPTLC-immunostaining method. However, the fatty acid and long chain base compositions of PC12 cell gangliosides (and their TLC mobility) differ from those of brain gangliosides.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
8.
Diurnal variations in response of rat liver tyrosine aminotransferase activity to food intake 总被引:1,自引:0,他引:1
Effects of fasting and refeeding on the hepatic tyrosine aminotransferase activity were examined in rats that had been fed during the night. The tyrosine aminotransferase activity showed clear diurnal variations, with a maximal activity after the feeding time. The tyrosine aminotransferase rhythm persisted even under starvation, though the amplitude decreased remarkably. When the starved rats were refed at night, the tyrosine aminotransferase activity increased rapidly to a high level, but it increased slowly to a rather lower level when they were refed in daytime. 相似文献
9.
Hideo Kurebayashi Akira Tanaka Tsutomu Yamaha 《Archives of biochemistry and biophysics》1982,215(2):433-443
The mechanism of microsomal oxidative deamination of alicyclic primary amines: cyclopentylamine, cyclohexylamine, cycloheptylamine, 1- and 2-aminoindan, 1- and 2-aminotetralin, was studied under an atmosphere of 18O2 or in a medium containing H218O. The oxygen-18 contents of the products determined by gas-liquid chromatography/mass spectrometry revealed that almost all (75–100 atom%) of the oxygen of oximes was derived from molecular oxygen, whereas a part (4–25 atom% ) of the oxygen of ketones. The studies on the hydrolysis of oximes and the oxygen exchange reaction of ketones proved that the latter proceeded at a considerable rate () and the former made a minor contribution, to explain why the major portion (75–96 atom%) of the oxygen in ketones was derived from water. The results support the mechanism that microsomal deamination proceeds mainly through a carbinolamine intermediate, which is initially hydroxylated at the α carbon to the amino group, partially equilibrating with the imine, and then rearranges to form a ketone and ammonia. 相似文献
10.
T Tadakuma T Yasuda A Tamura S Saito T Tsumita K Saito 《Journal of immunology (Baltimore, Md. : 1950)》1985,134(1):122-128
Various azobenzenearsonate-tyrosine (ABA-Tyr) derivatives were synthesized by modifying amino and carboxyl groups at the alpha-carbon of tyrosine, with preservation of most of the ABA-Tyr moiety (ABA plus hydroxyphenyl portion of tyrosine). These derivatives were tested for the ability to stimulate ABA-L-Tyr specific T cell lines derived from B10.BR and B10.S mice. ABA-acetyltyramine, ABA-hydroxyphenylpropionic acid (ABA-PPr), and ABA-propylphenol, which lack either the carboxyl or amino group or both, could not induce T cell proliferation. The lack of stimulation by these derivatives was not due to their cytotoxic effects. A similar pattern of proliferation was obtained on stimulating lymph node T cells from B10.BR and B10.S mice primed with ABA-L-Tyr. Some differences were observed, however, between B10.BR and B10.S mice. ABA-L-Tyr-specific T cells from B10.BR mice could not respond well to ABA-D-Tyr in contrast to B10.S T cells. Furthermore, B10.BR mice primed with ABA-acetyltyramine or ABA-PPr in complete Freund's adjuvant could not induce ABA-L-Tyr-reactive T cells, whereas T cells from B10.S mice primed with these derivatives could proliferate in the presence of ABA-L-Tyr. The differences between B10.BR and B10.S mice were further investigated by using (B10.S X B10.BR)F1 mice. T cells from ABA-L-Tyr-immunized F1 mice responded poorly to ABA-D-Tyr when presented with B10.BR antigen-presenting cells (APC), but responded well when presented with B10.S APC. Similarly, T cells from ABA-PPr-primed F1 mice did not proliferate to ABA-L-Tyr in the presence of B10.BR APC, but could proliferate in the presence of B10.S APC. Our results clearly indicate that the presence of charged groups at the alpha-carbon of tyrosine plays a critical role in the triggering of ABA-L-Tyr-specific T cell proliferation. The significance of these results is discussed. 相似文献