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991.
The antifungal activity of 2,4-dihydroxyacylophenones and related compounds against Trichophyton spp and other fungi were investigated to determine their structure-activity relationships.The activity of these compounds was found to be closely related to the length of the acyl and alkyl substituents attached to the 1,3-dihydroxybenzene moiety In addition, differences in activity were observed depending on the position of the alkyl substituents and on the number of substituents attached to the 1,3-dihydroxybenzene moiety. Some compounds tested showed potent antifungal activity against Trichophyton spp. and other fungi that was more active than amphotericin B. 相似文献
992.
Hiroji Sato Hirokazu Kawagishi Tsutomu Nishimura Syozou Yoneyama Yuko Yoshimoto Sadao Sakamura 《Bioscience, biotechnology, and biochemistry》2013,77(10):2969-2974
The structure of a new indole derivative, serotobenine (1), from sfflower meal (Carthamus tinctorius> L.) is proposed based on 1H- and 13C-NMR spectral data and X-ray crystallography. The known compounds N-feruloyltryptamine (2) and N-(p-coumaroyl)tryptamine (3) were also isolated and identified. 相似文献
993.
Takashi Watanabe Jiro Ohnishi Yuko Yamasaki Sumiko Kaizu Tetsuo Koshijima 《Bioscience, biotechnology, and biochemistry》2013,77(8):2233-2252
Lignin-carbohydrate complexes (LCC; nor-C-1-M, com-C-1-A) isolated from normal and compression woods of Pinus densiflora were hydrolyzed with two types of cellulase preparations, and the hydrolyzates formed were fractionated by adsorption chromatography on polyvinyl gel into water-soluble materials and LCC fragments. To elucidate the binding sites between the lignin and carbohydrate, the cellulase-degraded LCC fragments were subjected to acetylation, and then oxidation with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ), which was confirmed to oxidatively cleave the benzyl ether linkages between the lignin and carbohydrate. The DDQ-oxidized fraction was then methylated by the method of Prehm, hydrolyzed, reduced and acetylated. A GC-MS analysis of the methylated sugar revealed that alditol acetates from 6-O-methyl mannose, 6-O-methyl galactose, 6-O-methyl glucose and a small amount of their 2-O- or 3-O-methyl isomers existed in both methylated fractions. 2-O-Methyl xylose and 3-O-methyl xylose were also identified in the fraction from the acidic LCC (com-C-1-A). These results led to the conclusion that acetylglucomannan and β-1,4-galactan were preferably bound to the lignin at C-6 position of the hexoses, and that arabinoglucuronoxylan did likewise at the C-2 and C-3 positions of xylose units. 相似文献
994.
Koji Maeda Yuko Takamori Osamu Oka 《Bioscience, biotechnology, and biochemistry》2013,77(11):2873-2875
A droplet gel-entrapping method used for enzyme immobilization was improved to simplify the procedure and to increase the enzyme stability. This immobilization technique is suitable for coupled enzyme reactions requiring cofactors. Leucine dehydrogenase (LeuDH) and formate dehydrogenase (FDH) were freeze-dried with bovine serum albumin, dextrin and stabilizers. The freeze-dried enzyme powder was suspended in a methylcellosolve solution containing polyethyleneglycol(#4000)diacrylate, N,N′-methylenebisacrylamide and 2-hydroxyethylacrylate, and the suspension was gelled with initiators. The gel was cut up and the pieces were washed in a buffer to remove the methylcellosolve and the dextrin inside. The maximum conversion ratio for a LeuDH-FDH gel column was determined to be 99.8% by means of the recycling reaction. On longterm operation at 30 °C for leucine production, the initial conversion ratio (7.2%) gradually decreased to 6.6% over the first 10 days. However, the conversion ratio remained almost constant after the 10th day. The effects of flow rate, temperature, pH, and the concentrations of formate, α- ketoisocaproate, ammonium and NAD on the leucine productivity with the gel column were also investigated. 相似文献
995.
Naoki Kashimura Kichitaro Kawaguchi 《Bioscience, biotechnology, and biochemistry》2013,77(8):1621-1624
Sequential oxidation and reduction of aryl 4, 6-O-benzylidene-β-d-glucosides with dimethyl sulfoxide-phosphorus pentoxide mixture (DMSO–P2O5) and sodium borohydride were carried out as a new means for the preparation of aryl β-d-mannopyranoside derivatives. p-Nitrophenyl 4, 6-O-benzylidene-β-d-mannopyranoside was obtained in 22% yield from the corresponding glucoside 3-O-acetate, whereas from the unprotected acetal, 4, 6-O-benzylidene acetals of the corresponding mannoside and alloside were isolated in the yields of 6.7 and 2.1%, respectively. Similarly, phenyl 4, 6-O-benzylidene β-d-mannoside, alloside, and altroside were obtained from the corresponding glucoside in 2.2, 0.8 and 2.1% yields, respectively. 相似文献
996.
Yuma Kudo Akihiro Abe Kumiko Ito Yuko Cho Mari Yotsu-Yamashita 《Bioscience, biotechnology, and biochemistry》2013,77(11):1887-1894
Taxol was originally isolated from the yew Taxus brevifolia. Because taxol inhibits the depolymerization of microtubules, the presence of a self-resistance mechanism in Taxus spp. was hypothesized. The cloning of the cDNA for alpha and beta tubulins from Taxus cuspidata and those from the human embryonic kidney cell line HEK293T revealed that the 26Asp, 359Arg, and 361Leu residues in the human beta tubulin, which are important for taxol binding, were replaced with Glu, Trp, and Met in the beta tubulin of T. cuspidata, respectively. The microtubule assembly of the recombinant alpha and beta tubulins was monitored turbidimetrically, and the results clearly demonstrated that the microtubule from T. cuspidata is less sensitive to taxol than that from HEK293T cells. The Taxus microtubule composed of the wild-type alpha tubulin and the beta tubulin with the E26D mutation restored the sensitivity to taxol. We thus postulated that the mutation identified in the beta tubulin of T. cuspidata plays a role in the self-resistance of this species against taxol. 相似文献
997.
Akio Kobori Yuko Nagae Yuta Sugihara Asako Yamayoshi Akira Murakami 《Bioorganic & medicinal chemistry letters》2013,23(21):5825-5828
We developed a photoresponsive α-bromoaldehyde-conjugated oligonucleotide (PBA-ODN). The PBA-ODN selectively reacted and formed covalent bonds with target oligonucleotides having adenine or cytosine at the frontal position of the aldehyde derivative. Kinetic studies revealed that PBA-ODN has increased kinetic rates for the formation of cross-linked duplexes compared with the corresponding α-chloroaldehyde-conjugated oligonucleotide (PCA-ODN). 相似文献
998.
AMADA En Fukuda Kazumasa Kumagai Koshi Kawakubo Hirofumi Kitagawa Yuko 《Molecular and cellular biochemistry》2020,468(1-2):195-196
Molecular and Cellular Biochemistry - In the original article, Figs. 3b, 4a, c and 5d were published incorrectly. The correct version of the figures are provided in this correction. 相似文献
999.
Keiko Fujimoto Sanae Nakashima Shotaro Uchida Riham N.S. Amen Yuji Ishii Yuko Hirota Yoshitaka Tanaka 《Biochemistry and Biophysics Reports》2020
HM1.24 (also known as BST-2, CD317, and Tetherin) is a type II single-pass transmembrane glycoprotein, which traverses membranes using an N-terminal transmembrane helix and is anchored in membrane lipid rafts via a C-terminal glycosylphosphatidylinositol (GPI). HM1.24 plays a role in diverse cellular functions, including cell signaling, immune modulation, and malignancy. In addition, it also functions as an interferon-induced cellular antiviral restriction factor that inhibits the replication and release of diverse enveloped viruses, and which is counteracted by Vpu, an HIV-1 accessory protein. Vpu induces down-regulation and ubiquitin conjugation to the cytoplasmic domain of HM1.24. However, evidence for ubiquitination site(s) of HM1.24 remains controversial. We demonstrated that HM1.24 is constitutively poly-ubiquitinated at the N-terminal cytoplasmic domain, and that the mutation of all potential ubiquitination sites, including serine, threonine, cysteine, and lysine in the cytoplasmic domain of HM1.24, does not affect the ubiquitination of HM1.24. We further demonstrated that although a GPI anchor is necessary and sufficient for HM1.24 antiviral activities and virion-trapping, the deleted mutant of GPI does not influence the ubiquitination of HM1.24. These results suggest that the lipid raft localization of HM1.24 is not a prerequisite for the ubiquitination. Collectively, our findings demonstrate that the ubiquitination of HM1.24 occurs at the N-terminal amino acid in the cytoplasmic domain and indicate that the constitutive ubiquitination machinery of HM1.24 may differ from the Vpu-induced machinery. 相似文献