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381.
3-Acetamido-1,2-O-isopropylidene-3,5,6-trideoxy-d-ribo-hex-5-enofuranose and 3-acetamido-1,2-O-cyclohexylidene-3,5,6-trideoxy-d-xylo-hex-5-enofuranose were prepared from d-glucose. 相似文献
382.
Ethyl 2-benzamido-4,6-O-benzylidene-5-O-tosyl-2-deoxy-D-gluconate (III) was prepared from d-glucosamic acid. When treated with sodium acetate tosyloxy group on the fifth carbon of (III) was split off accompanying with a Walden inversion, and 2-benzamido-4,6-O-benzylidene-2-deoxy-2,3-l-idoseenic 1,5-lactone (IVa) was obtained. Since the tosyloxy group has no effective neighboring group for the inversion, its elimination was supposed to take place on the influence of carbonyl group of ester at δ-position, giving the lactone. 相似文献
383.
Hiroshi Ohrui Hiroyoshi Kuzuhara Sakae Emoto 《Bioscience, biotechnology, and biochemistry》2013,77(5):752-755
d-Oxybiotin (X) was synthesized from d-glucose and showed biotin activity for some microorganisms. 相似文献
384.
Sakae Watanabe Akio Kobayashi Kyohei Yamashita 《Bioscience, biotechnology, and biochemistry》2013,77(12):2919-2920
Properties of a glutathione transport system in T. ferrooxidans strain AP-44 were investigated using a reduced form of 35S-glutathione (35S-GSH). About 71.2% of the total radioactivity taken up into the cells was distributed in the cytosol fraction. The amount of GSH taken up into the cells was in proportion to the amount of ferrous iron oxidized. However, a high concentration of silver ions (50 mm), which completely inhibited an iron-oxidizing activity, did not inhibit the GSH transport. The results suggest that GSH was transported by using a proton electrochemical gradient formed across the cytoplasmic membrane. Since growth inhibition by silver nitrate was decreased by the addition of GSH to both silver ion sensitive-cells and resistant-cells, the GSH transport system may play some role in the silver ion resistance mechanism of the bacterium. 相似文献
385.
Hiroyoshi Kuzuhara Keiko Yakabi Hiroshi Ohrui Sakae Emoto 《Bioscience, biotechnology, and biochemistry》2013,77(2):285-288
The synthesis of (±)-epilupinine from trans-1-cyanoquinolizidines (IVa) and (IVb), the intermediates of the (±)-lamprolobine synthesis is described. 相似文献
386.
Benzyl 2, 3, 6-tri-O-acetyl-4-O-(2,3-di-O-acetyl-4,6-di-O-methylsulfonyl-β-d-glucopyranosyl)-β-d-glucopyranoside (VI) was prepared from α-cellobiose octaacetate. Displacement of the sulfonyl esters of VI with acyloxy-groups in N, N-dimethyl formamide in the presence of sodium benzoate gave 4-O-β-d-galactopyranosyl-d-glucopyranose derivative (lactose derivative). Elimination of blocking groups of the derivative yielded lactose hydrate (IX), though the overall yield of lactose from cellobiose octaacetate was less than 2%. 相似文献
387.
Nakada T Ishizuka Y Iwata T Toyoda F Kato T Conlon JM Kikuyama S 《Zoological science》2007,24(5):521-524
Sodefrin (Ser-Ile-Pro-Ser-Lys-Asp-Ala-Leu-Leu-Lys) is a female-attracting peptide pheromone secreted by the abdominal gland of the male red-bellied newt, Cynops pyrrhogaster. Sequence analysis of a cDNA encoding sodefrin revealed that the peptide is located in the C-terminal region of its precursor protein (residues 177-186 of preprosodefrin) and extended from its C-terminus by the tripeptide sequence Ile(187)-Ser(188)-Ala(189) and flanked at its N-terminus by Leu(174)-Gly(175)-Arg(176). This suggests that sodefrin is generated by enzymatic cleavage at monobasic (Lys and Arg) sites within the precursor molecule. To demonstrate the presence in the abdominal gland of proteolytic enzymes capable of generating sodefrin, an enzymatic assay was developed using t-butoxycarbo-nyl (Boc)-Leu-Gly-Arg-4methylcoumaryl-7-amide (MCA) and Boc-Leu-Leu-Lys-MCA as synthetic substrates. A crude extract of the abdominal gland hydrolyzed both substrates to liberate 7-amino-4- methylcoumarin, suggesting that enzymes that generate sodefrin from its precursor molecule are present in the gland. The activity in the extract for cleaving Boc-Leu-Gly-Arg-MCA was optimal at pH 9.0 and 45 degrees C and for Boc-Leu-Leu-Lys-MCA at pH 9.0 and 40 degrees C. The effects of a range of specific inhibitors on activities in the extract suggest an involvement of enzymes belonging to the serine protease family. It was also demonstrated that enzymatic activity in an extract of the abdominal glands of sexually developed males was significantly (three- to six-fold; p<0.01) higher than that of sexually undeveloped males. 相似文献
388.
Flower color alteration in <Emphasis Type="Italic">Lotus japonicus</Emphasis> by modification of the carotenoid biosynthetic pathway 总被引:1,自引:0,他引:1
Suzuki S Nishihara M Nakatsuka T Misawa N Ogiwara I Yamamura S 《Plant cell reports》2007,26(7):951-959
To establish a model system for alteration of flower color by carotenoid pigments, we modified the carotenoid biosynthesis
pathway of Lotus japonicus using overexpression of the crtW gene isolated from marine bacteria Agrobacterium aurantiacum and encoding β-carotene ketolase (4,4′-β-oxygenase) for the production of pink to red color ketocarotenoids. The crtW gene with the transit peptide sequence of the pea Rubisco small subunit under the regulation of the CaMV35S promoter was
introduced to L. japonicus. In most of the resulting transgenic plants, the color of flower petals changed from original light yellow to deep yellow
or orange while otherwise exhibiting normal phenotype. HPLC and TLC analyses revealed that leaves and flower petals of these
plants accumulated novel carotenoids, believed to be ketocarotenoids consisting of including astaxanthin, adonixanthin, canthaxanthin
and echinenone. Results indicated that modification of the carotenoid biosynthesis pathway is a means of altering flower color
in ornamental crops. 相似文献
389.