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101.
102.
Akira Kai Hiroko Karasawa Masayuki Kikawa Kenichi Hatanaka Kei Matsuzaki Tohru Mimura Yutaro Kaneko 《Carbohydrate polymers》1998,35(3-4):271-278
Biosynthesis of branched glucan by Pestalotiopsis from media containing D-(1-13C)glucose, D-(2-13C)glucose, D-(4-13C)glucose, D-(6-13C)glucose or a mixture of D-(1-13C)glucose and D-(2-13C)glucose was carried out to elucidate biosynthetic mechanism of branched polysaccharides. 13C NMR spectra of the labeled polysaccharides were determined and assigned. Analysis of 13C NMR spectra of glucitol acetates obtained from hydrolysates of the labeled branched polysaccharides indicated that transfer of labeling from C-1 to C-3 and C-6 carbons, from C-2 to C-1, C-3 and C-5 carbons, and from C-6 to C-1 carbon. From the results the percentages of routes via which the polysaccharide is biosynthesized are estimated. They show that the biosynthesis of the polysaccharide via the Embden-Meyerhof pathway and that from lipids and proteins are more active, and the pentose cycle is less active, than in the biosynthesis of cellulose and curdlan. As for the results, labeling at C-6 carbon in the branched polysaccharide cultured from D-(6-13C)glucose was low, compared to that of cellulose and curdlan. 相似文献
103.
Hirata N Yanagawa Y Ogura H Satoh M Noguchi M Matsumoto M Togashi H Onoé K Iwabuchi K 《Cellular immunology》2011,(2):165-171
In the present study, we examined the role of tumor necrosis factor (TNF) in interleukin (IL)-10 production by dendritic cells (DCs) using bone-marrow derived DCs from wild type (WT) and TNF-α knockout (TNF-α−/−) mice. Toll-like receptor (TLR) stimulation induced substantial level of IL-10 production by WT DCs, but significantly low level of IL-10 production by TNF-α−/− DCs. In contrast, no significant difference was detected in IL-12 p40 production between WT and TNF-α−/− DCs. Addition of TNF-α during TLR stimulation recovered the impaired ability of TNF-α−/− DCs for IL-10 production. This recovery appeared to be associated with an activation of extracellular signal-regulated kinase, p38 mitogen-activated protein kinase, and phosphatidylinositol 3-kinase/Akt following the TNF-α addition. Blocking these kinases significantly inhibited IL-10 production by TNF-α−/− DCs stimulated with TLR ligands plus TNF-α. Thus, TNF-α may be a key molecule to regulate the balance between anti-inflammatory versus inflammatory cytokine production in DCs. 相似文献
104.
Masayuki Ushio Hisato Fukuda Toshiki Inoue Kobayashi Makoto Osamu Kishida Keiichi Sato Koichi Murata Masato Nikaido Tetsuya Sado Yukuto Sato Masamichi Takeshita Wataru Iwasaki Hiroki Yamanaka Michio Kondoh Masaki Miya 《Molecular ecology resources》2017,17(6):e63-e75
Terrestrial animals must have frequent contact with water to survive, implying that environmental DNA (eDNA) originating from those animals should be detectable from places containing water in terrestrial ecosystems. Aiming to detect the presence of terrestrial mammals using forest water samples, we applied a set of universal PCR primers (MiMammal, a modified version of fish universal primers) for metabarcoding mammalian eDNA. The versatility of MiMammal primers was tested in silico and by amplifying DNAs extracted from tissues. The results suggested that MiMammal primers are capable of amplifying and distinguishing a diverse group of mammalian species. In addition, analyses of water samples from zoo cages of mammals with known species composition suggested that MiMammal primers could successfully detect mammalian species from water samples in the field. Then, we performed an experiment to detect mammals from natural ecosystems by collecting five 500‐ml water samples from ponds in two cool‐temperate forests in Hokkaido, northern Japan. MiMammal amplicon libraries were constructed using eDNA extracted from water samples, and sequences generated by Illumina MiSeq were subjected to data processing and taxonomic assignment. We thereby detected multiple species of mammals common to the sampling areas, including deer (Cervus nippon), mouse (Mus musculus), vole (Myodes rufocanus), raccoon (Procyon lotor), rat (Rattus norvegicus) and shrew (Sorex unguiculatus). Many previous applications of the eDNA metabarcoding approach have been limited to aquatic/semiaquatic systems, but the results presented here show that the approach is also promising even for forest mammal biodiversity surveys. 相似文献
105.
A Matsuda H Sugiura K Matsuyama H Matsumoto S Ichikawa K Komatsu 《Biochemical and biophysical research communications》1992,182(3):995-1001
Acetyl CoA: deacetylcephalosporin C o-acetyltransferase(DCPC-ATF) catalyses the final step in the biosynthesis of cephalosporin C, the conversion of deacetylcephalosporin C to cephalosporin C. A cDNA encoding DCPC-ATF has been isolated from a cDNA library of a cephalosporin C producing fungus Acremonium chrysogenum using oligonucleotide probes based on N-terminal amino acid sequences of the enzyme. The cDNA contains a single large open reading frame for a putative precursor consisting of 12 amino acid(AA) leader peptide of unknown function, 274 AA large subunit and 126 AA small subunit at the carboxyl end. The cDNA was expressed in yeast exhibiting a functional DCPC-ATF activity. It was also indicated that the leader peptide was not essential for expression of the enzyme activity. The primary structure of DCPC-ATF shows significant homology with those of acetyl CoA: homoserine o-acetyltransferase in Saccharomyces cerevisiae and Ascobolas immersus. 相似文献
106.
Katsunori Motosaka Masayuki Koganezawa Satoko Narikawa Akira Furuyama Kenji Shinozaki Kunio Isono Ichiro Shimada 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2007,193(2):279-283
Acute choice behavior in ingesting two different concentrations of sucrose in Drosophila is presumed to include learning and memory. Effects on this behavior were examined for four mutations that block associative
learning (dunce, rutabaga, amnesiac, and radish). Three of these mutations cause cyclic AMP signaling defects and significantly reduced taste discrimination. The exception
was radish, which affects neither. Electrophysiological recordings confirmed that the sensitivity of taste receptors is almost indistinguishable
in all flies, whether wild type or mutant. These results suggest that food choice behavior in Drosophila involves central nervous learning and memory operating via cyclic AMP signaling pathways. 相似文献
107.
Hiromoto Hisada Motoaki Sano Hiroki Ishida Yoji Hata Masayuki Machida 《Applied microbiology and biotechnology》2013,97(11):4951-4956
The Aspergillus oryzae glucoamylase-encoding gene glaB is expressed specifically and strongly only during solid-state cultivation (SSC). To elucidate the basis for the specificity, the glaB promoter was analyzed by electrophoretic gel mobility shift assay (EMSA) which indicated two protein-binding elements from ?382 to ?353 and from ?332 to ?313. To confirm that these regions contained cis-elements, deletion analysis of the promoter was undertaken using β-glucuronidase as a reporter. The results of the deletion analysis were consistent with the EMSA results. The promoter missing the ?332 to ?313 element was not induced by low water activity stress during SSC. 相似文献
108.
A naturally occurring functional allele of the rice waxy locus has a GT to TT mutation at the 5' splice site of the first intron 总被引:7,自引:0,他引:7
109.
Characterization of the cells in the repair tissue of full-thickness articular cartilage defects 总被引:1,自引:0,他引:1
H. Nakajima Tatsuhiko Goto Osamu Horikawa Toshiyuki Kikuchi Masayuki Shinmei 《Histochemistry and cell biology》1998,109(4):331-338
It is well established that a full-thickness articular cartilage defect is repaired with a fibrocartilaginous tissue, cells
of which are derived from undifferentiated mesenchymal stem cells in the bone marrow. To characterize the repair cells biochemically,
full-thickness defects were created in rabbit knee joints and the repair tissues taken at 3, 6, and 12 weeks after surgery.
The repair cells were cultured and examined biochemically to investigate the effects of four exogenous growth factors with
regard to the metabolism of type II collagen and proteoglycans. A significant increase of carboxy-terminal type II procollagen
peptide production was observed in the conditional medium of the repair cells, especially taken at 6 weeks after surgery,
in the presence of each growth factor. Glycosaminoglycan content was also increased and proteoglycan synthesis stimulated.
The repair cells taken at the early stage of the repair process could originally have more activity of type II collagen synthesis,
and the growth factors used could enhance the differentiation of the repair cells in vitro.
Accepted: 3 November 1997 相似文献
110.
Hideo Kawaguchi Alain A. Verts Shohei Okino Masayuki Inui Hideaki Yukawa 《Applied microbiology》2006,72(5):3418-3428
The aerobic microorganism Corynebacterium glutamicum was metabolically engineered to broaden its substrate utilization range to include the pentose sugar xylose, which is commonly found in agricultural residues and other lignocellulosic biomass. We demonstrated the functionality of the corynebacterial xylB gene encoding xylulokinase and constructed two recombinant C. glutamicum strains capable of utilizing xylose by cloning the Escherichia coli gene xylA encoding xylose isomerase, either alone (strain CRX1) or in combination with the E. coli gene xylB (strain CRX2). These genes were provided on a high-copy-number plasmid and were under the control of the constitutive promoter trc derived from plasmid pTrc99A. Both recombinant strains were able to grow in mineral medium containing xylose as the sole carbon source, but strain CRX2 grew faster on xylose than strain CRX1. We previously reported the use of oxygen deprivation conditions to arrest cell replication in C. glutamicum and divert carbon source utilization towards product production rather than towards vegetative functions (M. Inui, S. Murakami, S. Okino, H. Kawaguchi, A. A. Vertès, and H. Yukawa, J. Mol. Microbiol. Biotechnol. 7:182-196, 2004). Under these conditions, strain CRX2 efficiently consumed xylose and produced predominantly lactic and succinic acids without growth. Moreover, in mineral medium containing a sugar mixture of 5% glucose and 2.5% xylose, oxygen-deprived strain CRX2 cells simultaneously consumed both sugars, demonstrating the absence of diauxic phenomena relative to the new xylA-xylB construct, albeit glucose-mediated regulation still exerted a measurable influence on xylose consumption kinetics. 相似文献