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121.
Purification, Molecular Cloning, and Enzymatic Properties of a Family 12 Endoglucanase (EG-II) from Fomitopsis palustris: Role of EG-II in Larch Holocellulose Hydrolysis 下载免费PDF全文
Tomoko Shimokawa Hajime Shibuya Masanobu Nojiri Shigeki Yoshida Mitsuro Ishihara 《Applied microbiology》2008,74(18):5857-5861
A family 12 endoglucanase with a molecular mass of 23,926 Da (EG-II) from the brown-rot basidiomycete Fomitopsis palustris was purified and characterized. One of the roles of EG-II in wood degradation is thought to be to loosen the polysaccharide network in cell walls by disentangling hemicelluloses that are associated with cellulose. 相似文献
122.
Mari L. Shinohara Michiko Ihara Masanobu Abo Miyoko Hashida Shinobu Takagi Thomas C. Beck 《Applied microbiology and biotechnology》2001,57(5-6):653-659
A branching enzyme (EC 2.4.1.18) gene was isolated from an extremely thermophilic bacterium, Rhodothermus obamensis. The predicted protein encodes a polypeptide of 621 amino acids with a predicted molecular mass of 72 kDa. The deduced amino acid sequence shares 42-50% similarity to known bacterial branching enzyme sequences. Similar to the Bacillus branching enzymes, the predicted protein has a shorter N-terminal amino acid extension than that of the Escherichia coli branching enzyme. The deduced amino acid sequence does not appear to contain a signal sequence, suggesting that it is an intracellular enzyme. The R. obamensis branching enzyme was successfully expressed both in E. coli and a filamentous fungus, Aspergillus oryzae. The enzyme showed optimum catalytic activity at pH 6.0-6.5 and 65 degrees C. The enzyme was stable after 30 min at 80 degrees C and retained 50% of activity at 80 degrees C after 16 h. Branching activity of the enzyme was higher toward amylose than toward amylopectin. This is the first thermostable branching enzyme isolated from an extreme thermophile. 相似文献
123.
Masanobu Hayashi Tomoko Kuge Daiji Endoh Kenji Nakayama Jiro Arikawa Akira Takazawa Toyo Okui 《Experimental Animals》2002,51(1):43-48
Effects of accumulation of copper and iron on induction of DNA strand breaks were investigated in Long-Evans Cinnamon (LEC) rats that spontaneously develop fulminant hepatitis. Copper and iron accumulated in the liver of LEC rats in an age-dependent manner from 4 to 15 weeks. Low-iron diet prevented the accumulation of iron in the liver, but did not prevent accumulation of copper. The amounts of DNA strand breaks that were estimated by comet assay in the liver cells of rats fed standard diet increased with age from 4 to 15 weeks. No significant differences were observed in the proportions of LEC rat liver cells without tail and the average lengths of tail momentum in the comet images between LEC rats that had been fed standard MF diet and low-iron diet. These results support the idea that accumulation of iron is not directly associated with the induction of DNA damage in the liver cells of LEC rats. 相似文献
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Reactions of a single-cubane cluster [{Rh(cod)}2{MoCl(dtc)}2(μ3-S)4] (cod = 1,5-cyclooctadiene, dtc = diethyldithiocarbamate) with 1 equiv. of L (L = pyrazine, 4,4′-bipyridyl, trans-1,2-bis(4-pyridyl)ethylene) in the presence of 2 equiv. of AgBF4 in CH2Cl2 gave doubly bridged double-cubane clusters [({Rh(cod)}2{Mo(dtc)}2(μ3-S)4)2(μ-L)2][BF4]4, whose structures were determined by the single-crystal X-ray analysis. 相似文献
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128.
ABSTRACTCollagen-derived dipeptide prolyl hydroxyproline (Pro-Hyp) is involved in the proliferation and differentiation of various types of cultured cells. To elucidate the mechanism underlying Pro-Hyp actions during osteoblast differentiation, we hypothesized that proteins binding to Pro-Hyp serve to mediate cellular signaling, affecting Runx2 expression. Recently, we performed the characterization of Foxg1, that it enhances Runx2 expression in the presence of Pro-Hyp. Our findings indicate that Pro-Hyp directly binds to the Foxg1 recombinant protein, which leads to the structural alteration of the Foxg1 protein. In addition, Foxg1 appears to interact with Runx2 in the absence of Pro-Hyp, with Pro-Hyp disrupting the interaction between Foxg1 and Runx2. Collectively, our results indicate that the Pro-Hyp bound Foxg1 alters the structured conformation of Foxg1, resulting in conformational changes that lead to dissociation from Runx2. These novel findings suggest that during osteoblast differentiation, Pro-Hyp mediates Runx2 activity though directly binding to Foxg1 and increases Runx2 expression.Abbreviations: CPT: collagen peptide; GST: Glutathione S-transferase; PAGE: Polyacrylamide gel electrophoresis; PCR: Polymerase chain reaction; prolyl hydroxyproline: Pro-Hyp 相似文献
129.
Makaoto Goto Osamu Imamura Junro Kuromitsu Takehisa Matsumoto Yukako Yamabe Yoshiki Tokutake Noriyuki Suzuki Brian Mason Dennis Drayna Minoru Sugawara Masanobu Sugimoto Y. Furuichi 《Human genetics》1997,99(2):191-193
The profile of helicase gene mutations was studied in 89 Japanese Werner’s syndrome (WRN) patients by examining the previously
described mutations 1– 4 as well as a new mutation found during this study, designated mutation 5. Of 178 chromosomes (89
patients), 89 chromosomes (50%) had mutation 4, 11 (6.2%) chromosomes had mutation 1, and two chromosomes (1.1%) contained
mutation 5. Mutations 2 and 3 were not observed in this patient population. The remaining 76 (42.7%) chromosomes had none
of these mutations. A significant fraction of all patients (22 total patients, 24.7%) appear to be compound heterozygotes,
including those carrying mutations of both types 1 and 4. The genotype analysis of the markers surrounding the WRN helicase gene strongly suggests that most of the chromosomes carrying either mutation 1 or 4 were derived from two single
founders.
Received: 25 July 1996 / Revised: 20 September 1996 相似文献
130.
Shigeyuki Yamada Kazuyoshi Kohu Tomohiko Ishii Shigeto Ishidoya Shigeru Ishidoya Masayoshi Hiramatsu Satoru Kanto Atsushi Fukuzaki Yutsu Adachi Mareyuki Endoh Takuya Moriya Hiroki Sasaki Masanobu Satake Yoichi Arai 《DNA research》2004,11(5):335-344
Seminoma constitutes one subtype of human testicular germ cell tumors and is uniformly composed of cells that are morphologically similar to the primordial germ cells and/or the cells in the carcinoma in situ. We performed a genome-wide exploration of the genes that are specifically up-regulated in seminoma by oligonucleotide-based microarray analysis. This revealed 106 genes that are significantly and consistently up-regulated in the seminomas compared to the adjacent normal tissues of the testes. The microarray data were validated by semi-quantitative RT-PCR analysis. Of the 106 genes, 42 mapped to a small number of specific chromosomal regions, namely, 1q21, 2p23, 6p21-22, 7p14-15, 12pll, 12p13, 12q13-14 and 22q12-13. This list of up-regulated genes may be useful in identifying the causative oncogene(s) and/or the origin of seminoma. Furthermore, immunohistochemical analysis revealed that the seminoma cells specifically expressed the six gene products that were selected randomly from the list. These proteins include CCND2 and DNMT3A and may be useful as molecular pathological markers of seminoma. 相似文献