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81.
Yoshiya Ikawa Satoshi Touden Sho Katsumata Hiroyuki Furuta 《Bioorganic & medicinal chemistry》2013,21(21):6501-6505
A water-soluble derivative of N-fused porphyrin (NFP) possessing four cationic side-arms (pPyNFP) serves as a unique class of colorimetric/fluorogenic reporters that selectively react with biothiols in aquaous media to afford N-confused porphyrin (NCP) derivatives, while other nucleophilic amino acids were inert under a wide range of pH conditions. Owing to the large difference of the optical properties between NCP and NFP, the transformation enabled selective detection of biothiols in colorimetric/fluorogenic manner, especially in the near-infrared region. To the best our knowledge, this is the first example of porphyrin-based thiol detection systems that use the direct attack of thiol group on the optical reporter. 相似文献
82.
Shigemitsu Matsumoto Naoki Miyamoto Takaharu Hirayama Hideyuki Oki Kengo Okada Michiko Tawada Hidehisa Iwata Kazuhide Nakamura Seiji Yamasaki Hiroshi Miki Akira Hori Shinichi Imamura 《Bioorganic & medicinal chemistry》2013,21(24):7686-7698
To identify compounds with potent antitumor efficacy for various human cancers, we aimed to synthesize compounds that could inhibit c-mesenchymal epithelial transition factor (c-Met) and vascular endothelial growth factor receptor 2 (VEGFR2) kinases. We designed para-substituted inhibitors by using co-crystal structural information from c-Met and VEGFR2 in complex with known inhibitors. This led to the identification of compounds 3a and 3b, which were capable of suppressing both c-Met and VEGFR2 kinase activities. Further optimization resulted in pyrazolone and pyridone derivatives, which could form intramolecular hydrogen bonds to enforce a rigid conformation, thereby producing potent inhibition. One compound of particular note was the imidazo[1,2-a]pyridine derivative (26) bearing a 6-methylpyridone ring, which strongly inhibited both c-Met and VEGFR2 enzyme activities (IC50 = 1.9, 2.2 nM), as well as proliferation of c-Met-addicted MKN45 cells and VEGF-stimulated human umbilical vein endothelial cells (IC50 = 5.0, 1.8 nM). Compound 26 exhibited dose-dependent antitumor efficacy in vivo in MKN45 (treated/control ratio [T/C] = 4%, po, 5 mg/kg, once-daily) and COLO205 (T/C = 13%, po, 15 mg/kg, once-daily) mouse xenograft models. 相似文献
83.
Takashi Kuramoto Satoko Inoue Yuki Neoda Ken-ichi Yamasaki Ryoko Hashimoto Tomoji Mashimo Sen-ichi Oda Tadao Serikawa 《Mammalian genome》2013,24(7-8):303-308
Wild-derived rat strains can provide novel genome resources that are not available in standard laboratory strains. Genetic backgrounds of wild-derived strains can facilitate effective genetic linkage analyses and often modulate the expression of mutant phenotypes. Here we describe the development and characterization of a new inbred rat strain, DOB/Oda, from wild rats (Rattus norvegicus) captured in Shitara, Aichi, Japan. Phenotype analysis of 109 parameters revealed that the DOB/Oda rats had small body weight, preference for darkness, and high locomotor activity compared with the rat strains in the National BioResource Project for the Rat (NBRP-Rat) database. Genome analysis with 357 SSLP markers identified DOB/Oda-specific alleles in 70 markers. The percentage of SSLP markers that showed polymorphism between the DOB/Oda strain and any of 132 laboratory strains from NBRP-Rat varied from 89 to 95 %. The polymorphic rate (average of the values of the percentage) for the DOB/Oda strain was 91.6 %, much higher than the rates for available wild-derived strains such as the Brown Norway rat. A phylogenic tree constructed with DOB/Oda and all the strains in NBRP-Rat showed that the DOB/Oda strain localized within the wild rat groups, apparently separate from the laboratory strains. Together, these findings indicated that the DOB/Oda rat has a unique genome that is not available in the laboratory strains. Therefore, the new DOB/Oda strain will provide an important genome resource that will be useful for designing genetic experiments and for the discovery of genes that modulate mutant phenotypes. 相似文献
84.
An α-glucosidase and a glucoamylase have been isolated from fruit bodies of Lentinus edodes (Berk.) Sing., by a procedure including fractionation with ammonium sulfate, DEAE-cellulose column chromatography, and preparative gel electrofocusing. Both of them were homogeneous on gel electrofocusing and ultracentrifugation. The molecular weight of α-glucosidase and glucoamylase was 51,000 and 55,000, respectively. The α-glucosidase hydrolyzed maltose, maltotriose, phenyl α-maltoside, amylose, and soluble starch, but did not act on sucrose. The glucoamylase hydrolyzed maltose, maltotriose, phenyl α-maltoside, soluble starch, amylose, amylopectin, and glycogen, glucose being the sole product formed in the digests of these substrates. Both enzymes hydrolyzed phenyl a-maltoside into glucose and phenyl α-glucoside. The glucoamylase hydrolyzed soluble starch, amylose, amylopectin, and glycogen, converting them almost completely into glucose. It was found that β-glucose was liberated from amylose by the action of glucoamylase, while α-glucose was produced by the α-glucosidase.Maltotriose was the main α-glucosyltransfer product formed from maltose by the α-glucosidase. 相似文献
85.
86.
Yoshiki Yamasaki Toshio Miyake Yukio Suzuki 《Bioscience, biotechnology, and biochemistry》2013,77(2):251-259
Substrate and inhibitor specificities, and transglucosylation action of crystalline α-glucosidase from the mycelia of Mucor javanicus have been investigated. The enzyme hydrolyzed maltose, methyl-α-maltoside, and soluble starch liberating glucose, but little or not phenyl-α-glucoside, methyl-α-glucoside, sucrose, isomaltose, panose and dextran. The enzyme hydrolyzed phenyl-α-maltoside to glucose and phenyl-α-glucoside. The enzyme acted also as a glucosyltransferase when it was incubated with glucosyl donor such as maltose. Maltotriose was the principal transglucosylation product formed from maltose. The enzyme also catalyzed transglucosylation from maltose to riboflavin, pyridoxine, esculin and rutin. Tris and turanose inhibited the enzyme activity, but PCMB and EDTA did not. It is suggested that the enzyme activity is closely related to the histidine residue in the active center, from the inhibition experiments using diazonium-1-H-tetrazole and rose bengal. 相似文献
87.
Three forms of α-glucosidase have been isolated from 5-day-old green gram (Phaseolus vidissimus Ten.) seedlings, by a procedure including fractionation with ammonium sulfate and polyethylene glycol 6000, DEAE-cellulose column chromatography, SP-Sephadex column chromatography, preparative gel electrofocusing and preparative disc gel electrophoresis. The α-glucosidases isolated were designated as α-glucosidase I, α-glucosidase II–1 and α-glucosidase II–2. They were homogeneous on polyacrylamide disc gel electrophoresis. Their molecular weights were 145,000, 105,000 and 65,000, respectively. The three enzymes hydrolyzed maltose, maltotriose, phenyl α-maltoside, amylose and soluble starch liberating glucose, but did not act on sucrose. Their enzymes hydrolyzed phenyl α-maltoside into glucose and phenyl α-glucoside. They hydrolyzed amylose liberating α-glucose. Maltotriose was the main α-glucosyltransfer product formed from maltose by the three α-glucosidases. 相似文献
88.
Sho Matsui Takumi Yamane Kazuo Kobayashi-Hattori 《Bioscience, biotechnology, and biochemistry》2013,77(5):787-790
Transforming growth factor (TGF) β1-induced plasminogen activator inhibitor (PAI)-1 is one of factors associated with the development of hepatic fibrosis. Calcitonin gene-related peptide (CGRP) shows hepatoprotective effect during hepatic injuries, including fibrosis. However, the effects of CGRP on PAI-1 expression induced by TGFβ1 are unknown. In this study, we investigated the effect of CGRP on TGFβ1-induced PAI-1 expression and its regulatory mechanisms in HepG2 cells. CGRP inhibited TGFβ1-induced PAI-1 expression. H89, a protein kinase A inhibitor, abolished the inhibition of TGFβ1-induced PAI-1 expression by CGRP. TGFβ1 activated mitogen-activated protein kinase (MAPK), including extracellular signal-regulated kinase, c-jun NH2-terminal kinase, and p38, and this activation was abolished by CGRP. These results show that the CGRP-induced cAMP/PKA activation suppresses activation of MAPK induced by TGFβ1, leading to decreased PAI-1 expression in HepG2 cells. 相似文献
89.
Akira Tsuboi Yoshiki Yamasaki Yukio Suzuki 《Bioscience, biotechnology, and biochemistry》2013,77(3):543-550
Mucor rouxianus produced two forms (isoenzymes) of glucoamylase which could be separated from each other by polyacrylamide gel electrophoresis or by chromatography on SP-Sephadex C-50, and they were designated glucoamylase I and glucoamylase II. Glucoamylases I and II were isolated in crystalline form, and were homogeneous in poly acrylamide gel electrophoresis and in ultracentrifugation, respectively. The sedimentation coefficient () molecular weight of glucoamylase I were 4.39 S and 59,000, and those of glucoamylase II were 4.29 S and 49,000, respectively. 相似文献
90.
Yuji Shimizu Mio Nakazato Takaharu Sekita Koichiro Kadota Kazuhiko Arima Hironori Yamasaki Hisashi Goto Satoshi Shirahama Noboru Takamura Kiyoshi Aoyagi Takahiro Maeda 《Journal of physiological anthropology》2013,32(1):19