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1.
N. Yamada W. Murata Y. Yamaguchi K.-I. Fujita A. Ogita T. Tanaka 《Letters in applied microbiology》2021,72(4):390-398
Amphotericin B (AmB), a typical polyene macrolide antifungal agent, is widely used to treat systemic mycoses. In the present study, we show that the fungicidal activity of AmB was enhanced by benzyl isothiocyanate (BITC), a cruciferous plant-derived compound, in the budding yeast, Saccharomyces cerevisiae. In addition to forming a molecular complex with ergosterol present in fungal cell membranes to form K+-permeable ion channels, AmB has been recognized to mediate vacuolar membrane disruption resulting in lethal effects. BITC showed no effect on AmB-induced plasma membrane permeability; however, it amplified AmB-induced vacuolar membrane disruption in S. cerevisiae. Furthermore, the BITC-enhanced fungicidal effects of AmB significantly decreased cell viability due to the disruption of vacuoles in the pathogenic fungus Candida albicans. The application of the combinatorial antifungal effect of AmB and BITC may aid in dose reduction of AmB in clinical antifungal therapy and consequently decrease side effects in patients. These results also have significant implications for the development of vacuole-targeting chemotherapy against fungal infections. 相似文献
2.
Glyoxalase I was purified to apparent homogeneity from Pseudomonas putida. The enzyme was a monomer with a molecular weight of 20,000. The enzyme was most active at pH 8.0. The Km values for methylglyoxal and 4,5-dioxovale-rate are 3.5 mM and 1.2 mM, respectively. Contrary to the case of eukaryotic enzymes, chelating agents showed little inhibitory effects on the enzyme activity. Among the metal ions tested, Zn++ specifically and completely inhibited the activity of the enzyme at a millimolar level. The properties of bacterial glyoxalase I were quite different from mammalian and yeast enzymes. 相似文献
3.
Two kinds of water-soluble chlorophyll-protein complexes were prepared from leaves of Lepidium virginicum L., one (CP661) from the plant cultivated in a green house from seeds collected near Mono Lake, CA, and the other (CP-663) from a plant collected at Narashino, Chiba, Japan, by ammonium sulfate fractionation followed by column chromatography on DEAE-cellulose and Sephacryl S-200. The chlorophyll . proteins were further purified by crystallization. CP661 has absorption peaks at 661, 468, 439, 419, 380, 339 and 272 nm. CP663 had absorption peaks at 663, 469, 438, 419, 379, 338 and 272 nm. Estimated molecular weights were 78 000 for CP661 and 80 000 for CP663 by gel filtration chromatography and 83 000 for CP661 and 107 000 for CP663 by an equilibrium sedimentation method. 1 mol chlorophyll . protein contained 4 mol chlorophyll a and b with ratios of 1.0 in CP661 and 1.6 to 1.9 in CP663, but no carotenoids. These characters are different from those of chlorophyll-protein complexes which are prepared from the thylakoid membranes of chloroplasts with detergents. 相似文献
4.
Tatsuya Matsunami Toshihiro Suzuki Yasuo Hisa Kuniaki Takata Tetsuro Takamatsu Masahito Oyamada 《Cell communication & adhesion》2006,13(1):93-102
To elucidate the role of the spiral limbus in glucose transport in the cochlea, we analyzed the expression and localization of GLUT1, connexin26, connexin30, and occludin in the spiral limbus of the rat cochlea. GLUT1 and occludin were detected in blood vessels. GLUT1, connexin26, connexin30, and occludin were also expressed in fibrocytes just basal to the supralimbal lining cells. Connexin26 and connexin30 were present among not only these GLUT1-positive fibrocytes but also GLUT1-negative fibrocytes. In vivo glucose imaging using 6-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)amino]-6-deoxyglucose (6-NBDG, MW 342) together with Evans Blue Albumin (EBA, MW 68,000) showed that 6-NBDG was rapidly distributed throughout the spiral limbus, whereas EBA was localized only in the vessels. Moreover, the gap junctional uncoupler heptanol inhibited the distribution of 6-NBDG. These findings suggest that gap junctions play an important role in glucose transport in the spiral limbus, i.e., that gap junctions mediate glucose transport from GLUT1-positive fibrocytes to GLUT1-negative fibrocytes in the spiral limbus. 相似文献
5.
Expression of the fragile X site fra(X)(q27.3) was studied in thymidine-prototrophic and auxotrophic human-mouse somatic cell hybrids. In these cells, low thymidylate stress, achieved by 5-fluoro-2'-deoxyuridine (FdU) treatment and by limiting the exogenous supply of thymidine (dT), induced fragile X expression. High thymidylate stress, produced by supplying excess amounts of dT, was also effective in inducing fragile X expression, even in a hybrid clone that retained a fragile X chromosome as the only human chromosome; addition of deoxycytidine (dC) completely abolished this effect. In contrast, 5-bromo-2'-deoxyuridine (BrdU) did not induce fragile X expression. Cell-cycle analysis of BrdU-deprived thymidine-auxotrophic hybrid cells indicated that one round of DNA replication under thymidylate stress conditions is sufficient for fragile X expression. Our results suggest that the expression is an intrinsic property of the fragile site itself, which is believed to be composed of replicon clusters with pyrimidine-rich DNA sequence(s). 相似文献
6.
Jun Iwaki Kunio Kikuchi Yoshiaki Mizuguchi Yutaka Kawahigashi Hiroshi Yoshida Eiji Uchida Toshihiro Takizawa 《PloS one》2013,8(7)
MicroRNA miR-376c was expressed in normal intrahepatic biliary epithelial cells (HIBEpiC), but was significantly suppressed in the HuCCT1 intrahepatic cholangiocarcinoma (ICC) cell line. The biological significance of the down-regulation of miR-376c in HuCCT1 cells is unknown. We hypothesized that miR-376c could function as a tumor suppressor in these cells. To test this hypothesis, we sought the targets of miR-376c, and characterized the effect of its down-regulation on HuCCT1 cells. We performed proteomic analysis of miR-376c-overexpressing HuCCT1 cells to identify candidate targets of miR-376c, and validated these targets by 3′-UTR reporter assay. Transwell migration assays were performed to study the migratory response of HuCCT1 cells to miR-376c overexpression. Furthermore, microarrays were used to identify the signaling that were potentially involved in the miR-376c-modulated migration of HuCCT1. Finally, we assessed epigenetic changes within the potential promoter region of the miR-376c gene in these cells. Proteomic analysis and subsequent validation assays showed that growth factor receptor-bound protein 2 (GRB2) was a direct target of miR-376c. The transwell migration assay revealed that miR-376c significantly reduced epidermal growth factor (EGF)-dependent cell migration in HuCCT1 cells. DNA microarray and subsequent pathway analysis showed that interleukin 1 beta and matrix metallopeptidase 9 were possible participants in EGF-dependent migration of HuCCT1 cells. Bisulfite sequencing showed higher methylation levels of CpG sites upstream of the miR-376c gene in HuCCT1 relative to HIBEpiC cells. Combined treatment with the DNA-demethylating agent 5-aza-2′-deoxycytidine and the histone deacetylase inhibitor trichostatin A significantly upregulated the expression of miR-376c in HuCCT1 cells. We revealed that epigenetic repression of miR-376c accelerated EGF-dependent cell migration through its target GRB2 in HuCCT1 cells. These findings suggest that miR-376c functions as a tumor suppressor. Since metastasis is the major cause of death in ICC, microRNA manipulation could lead to the development of novel anti-cancer therapy strategies for ICC. 相似文献
7.
AbstractIn the present paper, computational efficiency of the hybrid Monte Carlo (HMC) method applied to the multicanonical ensemble is studied; the HMC is an equation of motion guided Monte Carlo method. As in the standard HMC for the canonical ensemble, the multicanonical HMC calculations with high acceptance ratio show better efficiency; about 60% acceptance yields the best performance for the system examined. 相似文献
8.
Labeled antibodies with different F/P molar ratios of FITC to protein (F/P molar ratio) were used for the detection of surface immunoglobulin (S-Ig) of human and mouse lymphocytes by membrane immunofluorescence, and the following results were obtained. 1. The percentage of S-Ig bearing cells increased markedly when labeled anti-human H- or L-chains antibodies were used with higher F/P molar ratios. The investigation of frozen kidney sections of mice injected with human immunoglobulin revealed that such an increase of the positive ratio in S-Ig was caused by increased non-specific adsorption of the fraction of labeled antibody with a high F/P molar ratio. 2. This non-specific adsorption phenomenon was observed at various intensities in materials from different species; materials from mcie showed less non-specific adsorption than those from humans. 3. It was possible to exclude reactivity with an Fc receptor using the top one third of the supernatant of labeled antibody centrifuged at 150,000 for 30 min. 相似文献
9.
Kunitoshi Yamanaka Teru Ogura Kazuyoshi Murata Toshinobu Suzaki Hironori Niki Sota Hiraga 《FEMS microbiology letters》1994,116(1):61-66
Abstract The smbA gene of Escherichia coli is essential for cell proliferation. The smbA2 mutant shows cold-sensitive colony formation at 22°C. A novel morphological phenotype, formation of a translucent segment at midcell or at a cell pole, was observed by phase-contrastt microscopy at a high frequency in the smbA2 mutant cells incubated in L medium lacking NaCl at 22°C, but not observed in L medium containing 1% NaCl or 20% sucrose at the same temperature. No translucent segment was observed in the wild-type cells in any of the media used. Electron microscopic observation revealed that the translucent segments resulted from the enlargement of a periplasmic space by separation of the inner membrane from the peptidoglycan layer and the outer membrane. 相似文献
10.
The Constituents of dermatan sulfate isomers in human articular cartilage were studied at the disaccharide level by high-performance liquid chromatography. Appreciable amounts of dermatan sulfate components, i.e., dermatan sulfate, chondroitin sulfate types G and B, could be detected after digestion with chondroitinases-B or -ABC. The oversulfated dermatan sulfate isomers were isolated only after digestion with chondroitinase-ABC but not with the AC-lyase. The dermatan sulfate isomers were found to be markedly increased in weight loading parts of articular cartilage. It is postulated that the dermatan sulfate isomers are formed as a result of the weight loading reaction, which may be responsible for the fibrosis of articular cartilage. 相似文献