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111.
A novel bacterium B9T was isolated from tidal flat sediment. Its morphology, physiology, biochemical features, and 16S rRNA gene sequence were characterized. Colonies of this strain are yellow and the cells are Gram-negative, rod-shaped, and do not require NaCl for growth. The 16S rRNA gene sequence similarity indicated that strain B9T is associated with the genus Lysobacter (≤ 97.2%), Xanthomonas (≤ 96.8%), Pseudomonas (≤ 96.7%), and Luteimonas (≤ 96.0%). However, within the phylogenetic tree, this novel strain shares a branching point with the species Luteimonas composti CC-YY255T (96.0%). The DNA-DNA hybridization experiments showed a DNA-DNA homology of 23.0% between strain B9T and Luteimonas mephitis B1953/27.1T. The G+C content of genomic DNA of the type strain is 64.7 mol% (SD, 1.1). The predominant fatty acids are iso-C11:0, iso-C15:0, iso-C16:0, iso-C17:0, iso-C17:0 ω9c, and iso-C11:0 3-OH. Combined analysis of the 16S rRNA gene sequences, fatty acid profile, and results from physiological and biochemical tests indicated that there is genotypic and phenotypic differentiation of the isolate from other Luteimonas species. For these reasons, strain B9T was proposed as a novel species, named Luteimonas aestuarii. The type strain of the new species is B9T (= KCTC 22048T, DSM 19680T).  相似文献   
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An L-arabinose isomerase of Escherichia coli was immobilized using covalent binding to agarose to produce D-tagatose, a bulking sweetener that can be economically used as a sugar substitute. The immobilized L-arabinose isomerase stably produced an average of 7.5 g-tagatose/L.day for 7 days with a productivity exceeding that of the free enzyme (0.47 vs 0.30 mg/U.day). Using a scaled-up immobilized enzyme system, 99.9 g-tagatose/L was produced from galactose with 20% equilibrium in 48 h. The process was repeated two more times with production of 104.1 and 103.5 g-tagatose/L. D-Tagatose production using an immobilized L-arabinose isomerase has a high potential for commercial application.  相似文献   
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Human embryonic stem (hES) cells are usually established and maintained on mouse embryonic fibroblast (MEFs) feeder layers. However, it is desirable to develop human feeder cells because animal feeder cells are associated with risks such as viral infection and/or pathogen transmission. In this study, we attempted to establish new hES cell lines using human uterine endometrial cells (hUECs) to prevent the risks associated with animal feeder cells and for their eventual application in cell-replacement therapy. Inner cell masses (ICMs) of cultured blastocysts were isolated by immunosurgery and then cultured on mitotically inactivated hUEC feeder layers. Cultured ICMs formed colonies by continuous proliferation and were allowed to proliferate continuously for 40, 50, and 55 passages. The established hES cell lines (Miz-hES-14, -15, and -9, respectively) exhibited typical hES cells characteristics, including continuous growth, expression of specific markers, normal karyotypes, and differentiation capacity. The hUEC feeders have the advantage that they can be used for many passages, whereas MEF feeder cells can only be used as feeder cells for a limited number of passages. The hUECs are available to establish and maintain hES cells, and the high expression of embryotrophic factors and extracellular matrices by hUECs may be important to the efficient growth of hES cells. Clinical applications require the establishment and expansion of hES cells under stable xeno-free culture systems.  相似文献   
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The, 3'-N-acyl-N-debenzoylpaclitaxel analogues 1a-d were synthesized and evaluated on biological systems. Some of the analogues 1a-d exhibited higher cytotoxicities (up to 20-fold) and stronger abilities to induce apoptosis than paclitaxel. In an in vivo experiment against i.p. implanted B16 melanoma, the most cytotoxic compound 1b in vitro caused tumor growth inhibition more than paclitaxel.  相似文献   
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Plant essential oils (EOs) exhibit an array of biological activities against insect pests. However, their negative influences on the pheromonal activity of azuki bean beetle (ABB), Callosobruchus chinensis L. have not received research attentions. ABB is a field‐to‐storage pest of legumes, and its female produces the sex pheromone known as homofarnesal with two isomeric components: 2E‐ and 2Z–homofarnesal, (2E,6E)‐7‐ethyl‐3,11‐dimethyl‐2,6,10‐dodecatrienals and (2Z,6E)‐7‐ethyl‐3,11‐dimethyl‐2,6,10‐dodecatrienals. We evaluated the effects of three EOs and their two major components on the attractiveness of male ABBs to synthetic homofarnesal (2E‐:2Z–homofarnesal = 6:4) using Y‐tube olfactometry in laboratory and rocket traps in the semi‐open polyhouse. Y‐tube olfactometry showed the significant negative effect of EOs of Illicium verum, Croton anisatum at 10 and 100 ng, and Gaultheria fragrantissima at 100 ng against homofarnesal (100 ng) in attracting male ABBs. Similarly trans‐anethole (at 10 and 100 ng) and methyl salicylate (at 100 ng) also ascertained significant negative effect against homofarnesal (100 ng) in Y‐tube olfactometry. When 10 mg of each of trans‐anethole and methyl salicylate was released at the downstream of 30 mg homofarnesal lure in rocket traps, highly significant effect was achieved against attractiveness of homofarnesal to ABB males. This study ascertained significant level of negative effect of the tested EOs and their major components to homofarnesal, tracing out a new opportunity of integrating them in ABB management programs both in field and storage.  相似文献   
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