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951.
Kongrit D Jisaka M Iwanaga C Yokomichi H Katsube T Nishimura K Nagaya T Yokota K 《Bioscience, biotechnology, and biochemistry》2007,71(2):491-498
A plant allene oxide synthase (AOS) reacting with 13S-hydroperoxy-9Z,11E,15Z-octadecatrienoic acid (13-HPOT), a lipoxygenase product of alpha-linolenic acid, provides an allene oxide which functions as an intermediate for jasmonic acid (JA) synthesis, making AOS a key enzyme regulating the JA level in plants. Although AOSs in various plants have been investigated, there is only limited information about AOSs in soybean (Glycine max). In this study, we cloned and characterized two soybean AOSs, GmAOS1 and GmAOS2, sharing 95% homology in the predicted amino acid sequences. GmAOS1 and GmAOS2 were composed of 564 and 559 amino acids respectively, with predicted N-terminal chloroplast-targeting signal peptides. Both AOSs expressed in Escherichia coli were selective for 13S-hydroperoxides of alpha-linolenic and linoleic acids, suggesting the potential of GmAOS1 and GmAOS2 to contribute to JA synthesis. GmAOS1 and GmAOS2 were expressed in leaves, stems, and roots, suggesting broad distribution in a soybean plant. 相似文献
952.
953.
We expressed and purified an azoreductase homolog, YvaB, from Bacillus subtilis. YvaB was found to have NADH:2,6-dichloroindophenol oxidoreductase activity, as well as azoreductase activity. Purified YvaB was active without FMN, unlike Escherichia coli azoreductase. YvaB was most active at pH 7.5 and 40 degrees C, and was stable up to 55 degrees C after incubation for 30 min. Remarkably, it was stable in the presence of Ag(+), and was activated by the addition of non-ionic detergents. Other enzymatic properties of YvaB were also investigated. 相似文献
954.
Induction of multiple cytokine secretion from RAW264.7 cells by alginate oligosaccharides 总被引:1,自引:0,他引:1
Yamamoto Y Kurachi M Yamaguchi K Oda T 《Bioscience, biotechnology, and biochemistry》2007,71(1):238-241
We investigated the cytokine-inducing activities of guluronate (G3-G6) and mannuronate (M3-M6) oligomers on RAW264.7 cells with the Bio-Plex assay system. Relatively high levels of tumor necrosis factor-alpha (TNF-alpha), granulocyte colony-stimulating factor (G-CSF), monocyte chemoattractant protein-1 (MCP-1), regulated upon activation normal T cell expressed and secreted (RANTES), granulocyte macrophage (GM)-CSF, and eotaxin were induced by alginate oligomers to different extents depending on the oligomer structures, and low but significant levels of interleukin (IL)-1alpha, IL-1beta, IL-6, IL-9, and IL-13 were also induced. Throughout all cytokines tested, M-oligomers tended to be more potent than G-oligomers in terms of cytokine induction, and this tendency was evident in differences between G3 and M3. 相似文献
955.
Lee JC Yokoyama T Hwang HJ Arimitsu H Yamamoto Y Kawasaki M Takigawa T Takeshi K Nishikawa A Kumon H Oguma K 《FEMS immunology and medical microbiology》2007,51(1):201-211
Type A neurotoxin of Clostridium botulinum was purified by a simple procedure using a lactose gel column. This procedure was previously reported for type B neurotoxin. Hemagglutinin-positive toxins (19S and 16S) were bound to the column under acid conditions, and the neurotoxin alone was dissociated from these hemagglutinin-positive toxins by changing the pH of the column to an alkaline condition. The toxicity of this purified toxin preparation was retained for at least 1 year at -30 degrees C by supplementing it with either 0.1% albumin or 0.05% albumin plus 1% trehalose. This preparation was used to treat 18 patients with urinary incontinence caused by refractory idiopathic and neurogenic detrusor overactivity; 16 of the patients showed excellent improvement. Improvements started within 1 week after injection in most cases and lasted 3-12 months [corrected] 相似文献
956.
Eguchi M Sekiya Y Suzuki M Yamamoto T Matsui H 《FEMS immunology and medical microbiology》2007,50(3):300-308
A single oral immunization with the Lon-protease-deficient Salmonella enterica serovar Typhimurium (strain CS2022) induced protective immunity in mice against a subcutaneous challenge with virulent Listeria monocytogenes as well as virulent Salmonella serovar Typhimurium. The populations of cell surface Toll-like receptor 4 (TLR4) and TLR2 on peritoneal macrophages decreased at week 6 after immunization. This population decrease was not reversed after a challenge with either Salmonella or Listeria. These results suggest that oral immunization with CS2022 induced immune tolerance correlated with the down-regulation of cell surface TLR expression. This down-regulation may in part account for the development of cross-protection against a Listeria challenge by immunization with CS2022. 相似文献
957.
Mineralization process during acellular cementogenesis in rat molars: a histochemical and immunohistochemical study using fresh-frozen sections 总被引:2,自引:2,他引:0
Yamamoto T Domon T Takahashi S Anjuman KA Fukushima C Wakita M 《Histochemistry and cell biology》2007,127(3):303-311
This study was designed to detect tissue non-specific alkaline phosphatase (TNSALP) by Azo-dye staining, calcium by glyoxal
bis (2-hydroxyanil) (GBHA) staining, bone sialoprotein (BSP) and osteopontin (OPN) by immunoperoxidase staining in developing
rat molars, and also to discuss the mineralization process during acellular cementogenesis. To restrain a reduction in histochemical
and immunohistochemical reactions, fresh-frozen undemineralized sections were prepared. Where the epithelial sheath was intact,
TNSALP reaction was observed in the dental follicle, but not in the epithelial sheath. With the onset of dentin mineralization,
the BSP- and OPN-immunoreactive, initial cementum layer appeared. At this point, cementoblasts had shown intense TNSALP reaction
and GBHA reactive particles (=calcium-GBHA complex) appeared on the root surface. With further development, the reaction of
TNSALP and GBHA became weak on the root surface. Previous studies have shown that the initial cementum is fibril-poor and
that matrix vesicles and calciferous spherules appear on the root surface only during the initial cementogenesis. The findings
mentioned above suggest that: during the initial cementogenesis, cementoblasts release matrix vesicles which result in calciferous
spherules, corresponding to the GBHA reactive particles. The calciferous spherules trigger the mineralization of the initial
cementum. After principal fiber attachment, mineralization advances along collagen fibrils without matrix vesicles. 相似文献
958.
Mizuha Y Yamamoto H Sato T Tsuji M Masuda M Uchida M Sakai K Taketani Y Yasutomo K Sasaki H Takeda E 《BioFactors (Oxford, England)》2007,30(2):105-116
It has been reported that Cordyceps sinensis, a traditional Chinese medicine, has various pharmacological effects. The aim of this study was to clarify the effect of water extract of Cordyceps sinensis (WECS) on osteoclast differentiation in vitro. In mouse bone marrow cells and monocyte/macrophage cell line RAW264.7, WECS dose-dependently inhibited the receptor activator of nuclear factor kappa B (NF-kappaB) ligand (RANKL)-induced osteoclast differentiation by tartrate-resistant acid phosphatase (TRAP) staining. In fact, cytotoxic effect was not observed in the RAW264.7 cells treated with WECS. Moreover, the mRNA expression of osteoclast related genes (calcitonin receptor, cathepsin K, matrix metalloprotease 9 and nuclear factor of activated T cells c1) was also inhibited by WECS. Investigation of inhibitory mechanism by using electrophoretic mobility shift assay (EMSA) and Western blot analysis revealed that WECS inhibited the activation of NF-kappaB through the prevention of IkappaBalpha phosphorylation. In conclusion, the present results demonstrate for the first time that WECS is a potent inhibitor of the RANKL-induced osteoclast differentiation through a mechanism involving the NF-kappaB pathway. 相似文献
959.
Shin M Kadowaki T Iwata J Kawakubo T Yamaguchi N Takii R Tsukuba T Yamamoto K 《Biological chemistry》2007,388(11):1173-1181
Cathepsin E (CE) is an intracellular aspartic proteinase implicated in various physiological and pathological processes, yet its actual roles in vivo remain elusive. To assess the physiological significance of CE expression in tumor cells, human CE was stably expressed in human prostate carcinoma ALVA101 cells expressing very little CE activity. Tumor growth in nude mice with xenografted ALVA101/hCE cells was slower than with control ALVA101/mock cells. Angiogenesis antibody array and ELISA assay showed that this was partly due to the increased expression of some antiangiogenic molecules including interleukin 12 and endostatin in tumors induced by CE expression. In vitro studies also demonstrated that, among the cathepsins tested, CE most efficiently generated endostatin from the non-collagenous fragment of human collagen XVIII at mild acidic pH. Histological examination revealed that tumors formed by ALVA101/hCE cells were partitioned by well-developed membranous structures and covered with thickened, well-stratified hypodermal tissues. In addition, both the number and extent of activation of tumor-infiltrating macrophages were more profound in ALVA101/hCE compared to ALVA101/mock tumors. The chemotactic response of macrophages to ALVA101/hCE cells was also higher than that to ALVA/mock cells. These results thus indicate that CE expression in tumor cells induces tumor growth arrest via inhibition of angiogenesis and enhanced immune responses. 相似文献
960.