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991.
Yasuo Shimizu Shigeki Matsuto Yasuyuki Mizunuma Ikunosuke Okada 《Bioscience, biotechnology, and biochemistry》2013,77(6):845-853
Seven weakly acidic compounds were newly detected as flavor components of roast barley by using column and gas-liquid chromatographies. These compounds were characterized and identified by MS, IR, UV and NMR spectroscopies and the mixed melting point test.These are 5-hydroxymaltol, maltol, 5-methylcyclopent-2-en-2-ol-1-one, phenol, m-cresol, pyrocatechol, resorcinol and an unidentified compound (MW 128). Maltol, 5-methylcyclopent-2-en-2-ol-1-one and 5-hydroxymaltol have so-called “sugary flavor,” and these compounds appear to concern with the sweet fragrant flavor of roast barley together with vanillin previously identified.Phenol, m-cresol, pyrocatechol and resorcinol which have a strong characteristic odor are supposed to concern with the smoky flavor of roast barley. 相似文献
992.
993.
Yasuhiro Fujita Shigeru Takahashi Yasuyuki Yamada 《Bioscience, biotechnology, and biochemistry》2013,77(6):1755-1759
We selected high-yield cell lines, using protoplast culture of Lithospermum erythrorhizon cells. Three cell lines having different shikonin productivities were used as parent cells for the selection, and cell lines with high productivity were obtained efficiently in every case. The best cell line had 6.45 g shikonin/g inoculum/23 days of production which was almost 1.5 times higher than that of the original cell line. The productivities of protoplast-derived cell lines were distributed widely and their average productivity was similar to the original one. The subculture of such a protoplast-derived cell line for eight months showed that its shikonin productivity was stabler than the original cell line. 相似文献
994.
Yasuyuki Uzuka Takafumi Naganuma Kentaro Tanaka Kiyoshi Suzuki 《Bioscience, biotechnology, and biochemistry》2013,77(3):851-852
In order to investigate the substrate binding feature of undecaprenyl diphosphate synthase from Micrococcus luteus B-P 26 with respect to farnesyl diphosphate and a reaction intermediate, (Z,E,E)-geranylgeranyl diphosphate, we examined the reactivity of artificial substrate analogs, 3-desmethyl farnesyl diphosphate and 3-desmethyl Z-geranylgeranyl diphosphate, which lack the methyl group at the 3-position of farnesyl diphosphate and Z-geranylgeranyl diphosphate, respectively. Undecaprenyl diphosphate synthase did not accept either of the 3-desmethyl analogs as the allylic substrate, indicating that the methyl group at the 3-position of the allylic substrate is important in the undecaprenyl diphosphate synthase reaction. These analogs showed different inhibition patterns in the cis-prenyl chain elongation reaction with respect to the reactions of farnesyl diphosphate and Z-geranylgeranyl diphosphate as allylic substrate. These results suggest that the binding site for the natural substrate farnesyl diphosphate and those for the intermediate allylic diphosphate, which contains the cis-prenyl unit, are different during the cis-prenyl chain elongation reaction. 相似文献
995.
996.
Zenyu Shiokawa Kentaro Hashimoto Bunnai Saito Yuya Oguro Hiroyuki Sumi Masato Yabuki Mie Yoshimatsu Yohei Kosugi Yasuyuki Debori Nao Morishita Douglas R. Dougan Gyorgy P. Snell Sei Yoshida Tomoyasu Ishikawa 《Bioorganic & medicinal chemistry》2013,21(24):7938-7954
We previously reported octahydropyrrolo[1,2-a]pyrazine derivative 2 (T-3256336) as a potent antagonist for inhibitors of apoptosis (IAP) proteins. Because compound 2 was susceptible to MDR1 mediated efflux, we developed another scaffold, hexahydropyrazino[1,2-a]indole, using structure-based drug design. The fused benzene ring of this scaffold was aimed at increasing the lipophilicity and decreasing the basicity of the scaffold to improve the membrane permeability across MDR1 expressing cells. We established a chiral pool synthetic route to yield the desired tricyclic chiral isomers. Chemical modification of the core scaffold led to a representative compound 50, which showed strong inhibition of IAP binding (X chromosome-linked IAP [XIAP]: IC50 23 nM and cellular IAP [cIAP]: IC50 1.1 nM) and cell growth inhibition (MDA-MB-231 cells: GI50 2.8 nM) with high permeability and low potential of MDR1 substrate. 相似文献
997.
Yutaka Mori Yasuyuki Ogawa Akiyoshi Mochizuki Yuji Nakamura Teppei Fujimoto Chie Sugita Shojiro Miyazaki Kazuhiko Tamaki Takahiro Nagayama Yoko Nagai Shin-ichi Inoue Katsuyoshi Chiba Takahide Nishi 《Bioorganic & medicinal chemistry》2013,21(18):5907-5922
We report synthesis and optimization of a series of (3S,5R)-5-(2,2-dimethyl-5-oxo-4-phenylpiperazin-1-yl)piperidine-3-carboxamides as renin inhibitors. Chemical modification of , and P3 portions led to a promising 3,5-disubstituted piperidine 32o showing high renin inhibitory activity and favorable oral exposure in both rats and cynomolgus monkeys with acceptable CYP and hERG current inhibition. Compound 32o exhibited a significant blood pressure lowering effect by oral administration in two hypertensive animal models, double transgenic rats and furosemide pretreated cynomolgus monkeys. 相似文献
998.
Goro Ishikawa Yasuyuki Seimiya Mika Saito Toshiki Nakamura Tsuguhiro Hoshino 《Molecular breeding : new strategies in plant improvement》2013,31(1):69-78
Japanese barnyard millet is an important food source in East Asian countries. However its crumbly texture limits desirability and consumption. Controlling amylose level in the endosperm is important to improve the eating quality of the millet. Because it is well known that the waxy gene determines the amylose level in the endosperm, we conducted a molecular analysis of the gene. Segregation analysis revealed that wild-type cultivars had three functional genes while low-amylose cultivars had one. We determined complete sequences of the three homoeologous waxy structural genes, EeWx1, EeWx2 and EeWx3, in a wild-type cultivar. These sequences showed high homology in the exon regions (97 %), and lower homology in the introns (82 %). Two spontaneous mutations were characterized in the low-amylose cultivars. In addition, one induced mutation was found in the fully waxy cultivar, Chojuromochi. Spontaneous mutations are deletions of whole and terminal regions in the EeWx2 and EeWx3 alleles, respectively. The induced mutation is a single-base deletion that led to a premature termination codon in EeWx1. These findings led us to develop useful markers for selecting low-amylose and waxy lines in millet. 相似文献
999.
Han B Izumi H Yasuniwa Y Akiyama M Yamaguchi T Fujimoto N Matsumoto T Wu B Tanimoto A Sasaguri Y Kohno K 《Biochemical and biophysical research communications》2011,(1):45-51
Ca2+/calmodulin-dependent protein kinase kinase (CaMKK) phosphorylates and activates specific downstream protein kinases including CaMKI, CaMKIV and 5′-AMP-activated protein kinase. In order to examine the variety of CaMKK-mediated signaling pathways, we searched for novel CaMKK substrate(s) using N6-(1-methylbutyl)-ATP and genetically engineered CaMKKα mutant, CaMKKα (Phe230Gly), that was capable of utilizing this ATP analogue as a phosphate donor. Incubation of rat brain extracts with recombinant CaMKKα (Phe230Gly), but not with wild-type kinase, in the presence of N6-(1-methylbutyl)-ATP and Ca2+/CaM, induced significant threonine phosphorylation of a 50 kDa protein as well as CaMKI phosphorylation at Thr177. The 50 kDa CaMKK substrate was partially purified by using serial column chromatography, and was identified as Syndapin I by LC-MS/MS analysis. We confirmed that recombinant Syndapin I was phosphorylated by CaMKKα and β isoforms at Thr355in vitro. Phosphorylation of HA-Syndapin I at Thr355 in transfected HeLa cells was significantly induced by co-expression of constitutively active mutants of CaMKK isoforms. This is the first report that CaMKK is capable of phosphorylating a non-kinase substrate suggesting the possibility of CaMKK-mediated novel Ca2+-signaling pathways that are independent of downstream protein kinases. 相似文献
1000.
Takanori Kihara Seyed Mohammad Ali Haghparast Yuji Shimizu Shunsuke Yuba Jun Miyake 《Biochemical and biophysical research communications》2011,(1):1
Mesenchymal stem cells (MSCs) have been extensively investigated for their applications in regenerative medicine. Successful use of MSCs in cell-based therapies will rely on the ability to effectively identify their properties and functions with a relatively non-destructive methodology.In this study, we measured the surface stiffness and thickness of rat MSCs with atomic force microscopy and clarified their relation at a single-cell level. The role of the perinuclear actin cap in regulating the thickness, stiffness, and proliferative activity of these cells was also determined by using several actin cytoskeleton-modifying reagents. This study has helped elucidate a possible link between the physical properties and the physiological function of the MSCs, and the corresponding regulatory role of the actin cytoskeleton. 相似文献