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101.
Suzuki Y Kurano M Arai Y Nakashita H Doi Y Usami R Horikoshi K Yamaguchi I 《Bioscience, biotechnology, and biochemistry》2002,66(12):2537-2542
Chemical regulation of secondary-metabolite synthesis was investigated through the improvement of poly-3-hydroxybutyrate (PHB) production in transgenic tobacco plants by the use of enzyme inhibitors. Two tobacco lines, BC3 and rCAB8, that produce PHB in both the cytosol and plastids were used. An acetyl-CoA carboxylase inhibitor, D-(+)-Quizalofop-ethyl, increased PHB accumulation in both lines 2-fold. The accumulation rate of plastidial PHB in the rCAB8 line was 2.5-fold higher than that of cytosolic PHB in the BC3 line. A specific inhibitor of 3-hydroxy-3-methylglutaryl-CoA reductase, mevastatin, also increased PHB accumulation but only in the BC3 line. These results indicated that chemical regulation of the native metabolic flows by the specific enzyme inhibitors increased secondary-metabolite production in the transgenic tobacco plants we used. 相似文献
102.
Kiguchi K Ishiwata I Tokieda Y Iguchi M Ishiwata C Iwata M Ishizuka B Yoshikawa H Tachibana T Hashimoto H Ishikawa H 《Human cell》2002,15(2):97-102
A cell line designated HUUCLEC was established from a human uterine cervical lymphoepithelial carcinoma obtained from a 61-year-old Japanese woman. The cell line has grown slowly without interruption and serial passages were successively carried out 60 times within 3 years. The cultured cells were spindle or round in shape, showing anaplastic and pleomorphic features, a pavement cell arrangement and multilayering without contact inhibition. The population doubling time of the HUUCLEC line was 72 hours while the chromosomal number varied widely and showed aneuploidy. The modal chromosomal number was stable at the triploid range and marker chromosomes were present; the Ebstein-Barr virus was absent in the cultured cells. 相似文献
103.
Masumoto K Ueda T Nagata M Yamada Y Yoshida Y Hashimoto Y Imoto T 《Protein and peptide letters》2002,9(5):435-439
We investigated thermal stabilities of four proteins in the presence of four kinds of sugars to analyze the mechanism of stabilization of proteins by additives. These proteins were stabilized by the addition of sugars, and the degree of stabilization correlated to the partial molar isentropic compressibility of the sugar. 相似文献
104.
105.
Ariyasu T Arai C Yoshizane C Kyono F Hanaya T Arai S Ikeda M Kurimoto M 《In vitro cellular & developmental biology. Animal》2002,38(1):30-34
The disaccharide trehalose has been shown to inhibit both bone loss in ovariectomized mice and excessive osteoclastogenesis in lipopolysaccharide-injected mice. However, the mechanism of osteoclastogenesis inhibition by oral administration of trehalose is still unclear. We report here for the first time that a human intestinal epithelial cell line, FHs74Int, also produces osteoprotegerin (OPG) and that trehalose augments OPG production by this cell line. Thus, these results suggest that trehalose promotes the production of OPG by intestinal epithelial cells, which then acts on bone marrow cells, resulting in the suppression of osteoclastogenesis. 相似文献
106.
A sex difference in the penetration of selenium into the brain was observed using lipopolysaccharide (LPS)-injected mice.
The selenium concentration increased in the brains of sodium selenite-injected LPS-treated female mice, but not males. The
selenium concentration peaked when selenite was injected 3 h after the injection of LPS into female mice. In addition, selenium
in the brain increased when a dosage of 30 μmol/kg and more of selenite was injected into LPS-treated female mice. Also, the
selenium concentration in the brain increased and peaked 2–3 h after selenite injection; 24 h later, the level was similar
to the Se-only group. The penetration of selenium into the brain was inhibited by pretreatment with aminoguanidine, an inhibitor
of nitric oxide synthetase. From the present results, selenium more easily penetrated into the brains of female mice compared
to males after LPS treatment, and nitric oxide may have affected the penetration. However, the sex difference mechanism for
selenium penetration needs further investigation. 相似文献
107.
108.
Impaired organic anion transport in kidney and choroid plexus of organic anion transporter 3 (Oat3 (Slc22a8)) knockout mice 总被引:8,自引:0,他引:8
Sweet DH Miller DS Pritchard JB Fujiwara Y Beier DR Nigam SK 《The Journal of biological chemistry》2002,277(30):26934-26943
To begin to develop in vivo model systems for the assessment of the contributions of specific organic anion transporter (OAT) family members to detoxification, development, and disease, we carried out a targeted disruption of the murine organic anion transporter 3 (Oat3) gene. Surviving Oat3(-/-) animals appear healthy, are fertile, and do not exhibit any gross morphological tissue abnormalities. No Oat3 mRNA expression was detected in kidney, liver, or choroid plexus (CP) of Oat3(-/-) mice. A distinct phenotype manifested by a substantial loss of organic anion transport capacity in kidney and CP was identified. Uptake sensitive to inhibition by bromosulfophthalein or probenecid was observed for taurocholate, estrone sulfate, and para-aminohippurate in renal slices from wild-type mice, whereas in Oat3(-/-) animals transport of these substances was greatly reduced. No discernable differences in uptake were observed between hepatic slices from wild-type and Oat3(-/-) littermates, suggesting Oat3 does not play a major role in hepatic organic anion uptake. Cellular accumulation of fluorescein was reduced by approximately 75% in CP from Oat3(-/-) mice. However, capillary accumulation of fluorescein-methotrexate was unchanged, indicating the effects of Oat3 loss are restricted to the entry step and that Oat3 is localized to the apical membrane of CP. These data indicate a key role for Oat3 in systemic detoxification and in control of the organic anion distribution in cerebrospinal fluid. 相似文献
109.
Shima J Sakata-Tsuda Y Suzuki Y Nakajima R Watanabe H Kawamoto S Takano H 《Applied and environmental microbiology》2003,69(1):715-718
The effect of intracellular charged amino acids on freeze tolerance in dough was determined by constructing homozygous diploid arginase-deficient mutants of commercial baker's yeast. An arginase mutant accumulated higher levels of arginine and/or glutamate and showed increased leavening ability during the frozen-dough baking process, suggesting that disruption of the CAR1 gene enhances freeze tolerance. 相似文献
110.
Nakahara Y Nonaka T Hojo H Nakahara Y 《Bioscience, biotechnology, and biochemistry》2003,67(8):1761-1766
An unnatural alpha-D-mannopyranose-linked chitobiosyl dolichyl pyrophosphate, a stereoisomer of the N-glycan biosynthesis intermediate, was synthesized. The protected trisaccharide, alpha-D-Man-(1-->4)-beta-D-GlcNAc-(1-->4)-D-GlcNAc, carrying a 4-methylbenzoyl group was prepared for the convenience of a TLC analysis. 1-O-Phosphorylation, condensation with dolichyl phosphate, and subsequent deprotection afforded the title compound. 相似文献