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Ohne ZusammenfassungMit 2 TextabbildungenDiese Arbeit wurde mit Unterstützung der Deutschen Forschungsgemeinschaft durchgeführt.  相似文献   
53.
Simple and convenient method for culturing anaerobic bacteria.   总被引:1,自引:0,他引:1       下载免费PDF全文
A simple and convenient method for culturing anaerobic bacteria is described. Cultures can be grown in commercially available flasks normally used for preparation of sterile external solutions. A special disposable rubber flask closure maintains anaerobic conditions in the flask after autoclaving. Growth of a variety of anaerobic oral bacteria was comparable to that obtained after anaerobic incubation of broth cultures in Brewer Anaerobic Jars.  相似文献   
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Porphobilinogen deaminase, the polymerase that catalyses the synthesis of preuroporphyrinogen, the linear tetrapyrrole precursor of uroporphyrinogen III, has been crystallized from sodium acetate buffer with polyethylene glycol 6000 as precipitant. The crystals are orthorhombic and the space group is P2(1)2(1)2, with unit cell dimensions a = 88.01 A, b = 75.86 A, c = 50.53 A and alpha = beta = gamma = 90 degrees, indicating a single molecule of 34 kDa in the asymmetric unit. The crystals grow to dimensions of 1 mm x 2 mm x 0.5 mm within two weeks in the dark and are stable in the X-ray beam for at least 40 hours. Diffraction data beyond 1.7 A resolution, observed with a synchrotron radiation source, indicate that a high resolution structure analysis is feasible.  相似文献   
55.
Jordan  Frank  Nemeria  Natalia  Gerfen  Gary 《Neurochemical research》2019,44(10):2325-2335
Neurochemical Research - According to recent findings, the human 2-oxoglutarate dehydrogenase complex (hOGDHc) could be an important source of the reactive oxygen species in the mitochondria and...  相似文献   
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As part of our ongoing efforts to develop reversible inhibitors of LSD1, we identified a series of 4-(pyrrolidin-3-yl)benzonitrile derivatives that act as successful scaffold-hops of the literature inhibitor GSK-690. The most active compound, 21g, demonstrated a Kd value of 22 nM and a biochemical IC50 of 57 nM. In addition, this compound displayed improved selectivity over the hERG ion channel compared to GSK-690, and no activity against the related enzymes MAO-A and B. In human THP-1 acute myeloid leukaemia cells, 21g was found to increase the expression of the surrogate cellular biomarker CD86. This work further demonstrates the versatility of scaffold-hopping as a method to develop structurally diverse, potent inhibitors of LSD1.  相似文献   
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The seasonal patterns in concentrations of both soluble (NSC-S)and insoluble (NSC-I) non-structural carbohydrates, in 3-year-oldpeach trees (Prunus persica L. Batsch) grown in sand cultureare described. The ability of trees to mobilize their carbohydratereserves in response to scion-trunk girdling, which preventsphotosynthate transport toward the roots, was tested at fourphenological stages. Girdling induces a NSC-I depletion in rootsand rootstock-trunk bark and a NSC-I accumulation in leavesand shoots. On the contrary, the NSC-S concentrations of theorgans located both above and below girdling were not significantlyaffected by the treatment. Consequently, when phloem transportbreaks down, trees, whatever their growing stage, mobilize carbohydratereserves below the girdle to maintain the soluble sugar contentsat the same level as in control trees. Key words: Girdling, non-structural carbohydrates, Prunus persica L., carbon reserves, seasonal patterns  相似文献   
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Smith-Lemli-Opitz syndrome (SLOS) is an inherited autosomal recessive cholesterol deficiency disorder. Our studies have shown that in SLOS children, urinary mevalonate excretion is normal and reflects hepatic HMG-CoA reductase activity but not ultimate sterol synthesis. Hence, we hypothesized that in SLOS there may be increased diversion of mevalonate to nonsterol isoprenoid synthesis. To test our hypothesis, we measured urinary dolichol and ubiquinone, two nonsterol isoprenoids, in 16 children with SLOS and 15 controls, all fed a low-cholesterol diet. The urinary excretion of both dolichol (P < 0.002) and ubiquinone (P < 0.02) in SLOS children was 7-fold higher than in control children, whereas mevalonate excretion was comparable. In a subset of 12 SLOS children, a high-cholesterol diet decreased urinary mevalonate excretion by 61% (P < 0.001), dolichol by 70% (P < 0.001), and ubiquinone by 67% (P < 0.03). Our hypothesis that in SLOS children, normal urinary mevalonate excretion results from increased diversion of mevalonate into the production of nonsterol isoprenoids is supported. Dietary cholesterol supplementation reduced urinary mevalonate and nonsterol isoprenoid excretion but did not change the relative ratios of their excretion. Therefore, in SLOS, a secondary peripheral regulation of isoprenoid synthesis may be stimulated.  相似文献   
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