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81.
Tatsushi Mogi Kazunobu Matsushita Yoshiro Murase Kenji Kawahara Hideto Miyoshi Hideaki Ui Kazuro Shiomi Satoshi mura & Kiyoshi Kita 《FEMS microbiology letters》2009,291(2):157-161
In bacterial membranes and plant, fungus and protist mitochondria, NADH dehydrogenase (NDH-II) serves as an alternative NADH : quinone reductase, a non-proton-pumping single-subunit enzyme bound to the membrane surface. Because NDH-II is absent in mammalian mitochondria, it is a promising target for new antibiotics. However, inhibitors for NDH-II are rare and unspecific. Taking advantage of the simple organization of the respiratory chain in Gluconobacter oxydans , we carried out screening of natural compounds and identified scopafungin and gramicidin S as inhibitors for G. oxydans NDH-II. Further, we examined their effects on Mycobacterium smegmatis and Plasmodium yoelii NDH-II as model pathogen enzymes. 相似文献
82.
K Kogi 《Journal of human ergology》1989,18(1):147-150
Recent ILO experiences show that concrete ergonomics improvements can result from learning-by-doing training in real settings. Particularly important is to build on local practice focusing on good examples already available. Checklist exercise, demonstrating low-cost solutions and group work are effective training tools. Opportunities can be widely created by such enabling training. 相似文献
83.
A high molecular weight aliphatic polythioester was prepared by lipase-catalyzed polymerization of hexane-1,6-dithiol and dimethyl sebacate using the technique of ring-opening polymerization of a cyclic thioester. The cyclic thioester monomer was first prepared using lipase from Candida antarctica in dilute solution. The monomer was then polymerized by the same lipase in bulk to produce a polythioester with an M(w) of about 120 000 g/mol, which was significantly higher than that of a polythioester obtained by direct polycondensation of the dithiol and diacid. The polymerization rate and thermal properties of the product were measured and compared with those of the corresponding polyester prepared by ring-opening polymerization of a cyclic ester. 相似文献
84.
Murakami Y Kanzawa N Saito K Krawitz PM Mundlos S Robinson PN Karadimitris A Maeda Y Kinoshita T 《The Journal of biological chemistry》2012,287(9):6318-6325
Hyperphosphatasia mental retardation syndrome (HPMR), an autosomal recessive disease characterized by mental retardation and elevated serum alkaline phosphatase (ALP) levels, is caused by mutations in the coding region of the phosphatidylinositol glycan anchor biosynthesis, class V (PIGV) gene, the product of which is a mannosyltransferase essential for glycosylphosphatidylinositol (GPI) biosynthesis. Mutations found in four families caused amino acid substitutions A341E, A341V, Q256K, and H385P, which drastically decreased expression of the PIGV protein. Hyperphosphatasia resulted from secretion of ALP, a GPI-anchored protein normally expressed on the cell surface, into serum due to PIGV deficiency. In contrast, a previously reported PIGM deficiency, in which there is a defect in the transfer of the first mannose, does not result in hyperphosphatasia. To provide insights into the mechanism of ALP secretion in HPMR patients, we took advantage of CHO cell mutants that are defective in various steps of GPI biosynthesis. Secretion of ALP requires GPI transamidase, which in normal cells, cleaves the C-terminal GPI attachment signal peptide and replaces it with GPI. The GPI-anchored protein was secreted substantially into medium from PIGV-, PIGB-, and PIGF-deficient CHO cells, in which incomplete GPI bearing mannose was accumulated. In contrast, ALP was degraded in PIGL-, DPM2-, or PIGX-deficient CHO cells, in which incomplete shorter GPIs that lacked mannose were accumulated. Our results suggest that GPI transamidase recognizes incomplete GPI bearing mannose and cleaves a hydrophobic signal peptide, resulting in secretion of soluble ALP. These results explain the molecular mechanism of hyperphosphatasia in HPMR. 相似文献
85.
86.
Toshima K 《Carbohydrate research》2006,341(10):1282-1297
In this short review article, several glycosylation methods that were developed in our laboratories, including stereocontrolled glycosylation using 2,6-anhydro-2,6-dideoxy-2,6-dithio sugars for obtaining 2,6-dideoxy glycosides, C-glycosylation employing unprotected sugars, environmentally benign glycosylation utilizing heterogeneous solid acids and ionic liquids, are recounted. In addition, representative and significant applications of these methods to the synthesis of complex natural products are described. 相似文献
87.
88.
Toshihide Hirao Masashi Murakami Hiroyuki Kogi Akira Kashizaki Yoshiyuki Hirai Shin-ich Tanabe Naoki Inari Hiroshi Yorozuya Masanori J. Toda 《Ecological Research》2006,21(6):811-818
An international project, DIWPA-IBOY, took place for simultaneously observing biodiversity throughout the Western-Pacific
and Asian regions in 2001–2003, as one of the core projects for International Biodiversity Observation Year, a crosscutting
network activity of DIVERSITAS (an international programme of biodiversity science). DIWPA-IBOY provides extensive data on
species diversity obtained by the standardized method. Under this project, 51,742 individuals of Lepidoptera and 11,633 of
Coleoptera were collected by light traps from the Tomakomai Experimental Forest of Hokkaido University, one of the core DIWPA-IBOY
sites, in the cool-temperate region of northern Japan. Based on these data, this study examined the relative abundance distribution
(RAD) to evaluate the amount of rare species in the Lepidoptera and Coleoptera communities. The beta diversities between sampling
seasons, forest strata, and trap sites were also assessed to evaluate the spatio-temporal variability of species composition
in these communities. In the analysis of the RAD, the best-fit model was selected from the log-Normal, Zipf–Mandelbrot, and
Zipf models differing in the tail length of the RAD, i.e., the proportion of rare species. To explore the beta diversity between
samples, the abundance-based Jaccard index with an unseen species estimator was calculated, and then a hierarchical clustering
analysis was conducted. As a result of RAD analysis, the Coleoptera community was regarded as containing a larger proportion
of rare species than the Lepidoptera community. The seasonal compartmentalization of the community, deduced from the beta-diversity
analysis, was finer in Lepidoptera (seven assemblages recognized) than in Coleoptera (three assemblages). The spatial (vertical
and horizontal) compartmentalization was negligible in both communities. The coincidence of the larger proportion of rare
species and the lower beta diversity between seasons in the Coleoptera community was explained by the longer life spans of
beetles compared to moths, based on the assumption that the length of life span acts as a temporal agent for mass effect on
the analogy of the migration rate as a spatial agent for mass effect. 相似文献
89.
Shinagawa E Toyama H Matsushita K Tuitemwong P Theeragool G Adachi O 《Bioscience, biotechnology, and biochemistry》2006,70(4):850-857
Membrane-bound NADP-independent formaldehyde-oxidizing enzyme was purified to homogeneity from the membrane of Acetobacter sp. SKU 14 isolated in Thailand. The enzyme was solubilized from the membrane fraction of glycerol-grown cells with 1% Tween 20 at pH 2.85, and purified to homogeneity through the steps of column chromatographies on DEAE-Sephadex A-50 and Q-Sepharose in the presence of 0.1% Tween 20 and 0.1% Triton X-100. The enzyme purified together with a cytochrome c showed a single protein band on native-PAGE, and was dissociated into three different subunits upon SDS-PAGE with molecular masses of 78 kDa, 55 kDa, and 18 kDa. The purified enzyme was finally characterized as a quinoprotein alcohol dehydrogenase (QADH), and this is the first indication that QADH highly oxidizes formaldehyde. The substrate specificity of the enzyme was found to be broad toward aldehydes and alcohols, and alcohols, especially n-butanol, n-propanol, and ethanol, were oxidized more rapidly than formaldehyde. 相似文献
90.
Deeraksa A Moonmangmee S Toyama H Adachi O Matsushita K 《Bioscience, biotechnology, and biochemistry》2006,70(10):2536-2539
Acetobacter tropicalis SKU1100 produces a pellicle-forming capsular polysaccharide (CPS), consisting of galactose, glucose, and rhamnose. We cloned the galE gene, a UDP-galactose synthesis gene, from A. tropicalis SKU1100 by PCR. A galE-disruptant was prepared and found not to produce CPS and thus not to form a pellicle under the static condition. Instead, the DeltagalE mutant secreted an extracellular polysaccharide (EPS), which was purified and found to have a unique character, different from the original CPS. 相似文献