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11.
An ammonia-oxidizing bacterium was isolated from a sample of brackish water (North Sea, Harbour of Husum). It is a motile large coccus 1.5–1.7 m in diameter. The extensive cytomembrane system occurring as flattened vesicles in the peripheral region of the cytoplasm and as intrusions into the center of the cytoplasm is to be emphasized as a characteristic mark of identification. The lithoauto-trophically growing bacterium turned out to be an obligate halophile. Because of its physiological and morphological properties, we assigned it to the genus Nitrosoccus and propose the name Nitrosococcus mobilis. 相似文献
12.
Niclas Franck Michael Maris Sarah Nalbandian Saswata Talukdar Simon Schenk Hans-Peter Hofmann David Bullough Olivia Osborn 《PloS one》2014,9(9)
Interleukin 1 Receptor antagonist (IL-1Ra) is highly elevated in obesity and is widely recognized as an anti-inflammatory cytokine. While the anti-inflammatory role of IL-1Ra in the pancreas is well established, the role of IL-1Ra in other insulin target tissues and the contribution of systemic IL-1Ra levels to the development of insulin resistance remains to be defined. Using antisense knock down of IL-1Ra in vivo, we show that normalization of IL-1Ra improved insulin sensitivity due to decreased inflammation in the liver and improved hepatic insulin sensitivity and these effects were independent of changes in body weight. A similar effect was observed in IL1-R1 KO mice, suggesting that at high concentrations of IL-1Ra typically observed in obesity, IL-1Ra can contribute to the development of insulin resistance in a mechanism independent of IL-1Ra binding to IL-1R1. These results demonstrate that normalization of plasma IL-1Ra concentration improves insulin sensitivity in diet- induced obese mice. 相似文献
13.
Stich B Melchinger AE Piepho HP Hamrit S Schipprack W Maurer HP Reif JC 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》2007,115(4):529-536
Knowledge about the forces generating and conserving linkage disequilibrium (LD) is important for drawing conclusions about
the prospects and limitations of association mapping. The objectives of our research were to examine the importance of (1)
selection, (2) mutation, and (3) genetic drift for generating LD in a typical maize breeding program. We conducted computer
simulations based on genotypic data of Central European maize open-pollinated varieties which have played an important role
as founders of the European flint heterotic group. The breeding scheme and the dimensioning underlying our simulations reflect
essentially the maize breeding program of the University of Hohenheim. Results suggested that in a plant breeding program
of the examined dimension and breeding scheme, genetic drift and selection are major forces generating LD. The currently used
population-based association mapping tests do not explicitly correct for LD caused by these two forces. Therefore, increased
type I error rates are expected if these tests are applied to plant breeding populations. As a consequence, we recommend to
use family-based association tests for association mapping approaches in plant breeding populations. 相似文献
14.
Anna U?arowska Giuseppe Dionisio Barbara Sarholz Hans-Peter Piepho Mingliang Xu Christina R?nn Ingvardsen Gerhard Wenzel Thomas Lübberstedt 《BMC plant biology》2009,9(1):15
Background
The potyviruses sugarcane mosaic virus (SCMV) and maize dwarf mosaic virus (MDMV) are major pathogens of maize worldwide. Two loci, Scmv1 and Scmv2, have ealier been shown to confer complete resistance to SCMV. Custom-made microarrays containing previously identified SCMV resistance candidate genes and resistance gene analogs were utilised to investigate and validate gene expression and expression patterns of isogenic lines under pathogen infection in order to obtain information about the molecular mechanisms involved in maize-potyvirus interactions. 相似文献15.
16.
Timo Heinrich Hans-Peter Buchstaller Bertram Cezanne Felix Rohdich Jörg Bomke Manja Friese-Hamim Mireille Krier Thorsten Knöchel Djordje Musil Birgitta Leuthner Frank Zenke 《Bioorganic & medicinal chemistry letters》2017,27(3):551-556
The natural product fumagillin 1 and derivatives like TNP-470 2 or beloranib 3 bind to methionine aminopeptidase 2 (MetAP-2) irreversibly. This enzyme is critical for protein maturation and plays a key role in angiogenesis. In this paper we describe the synthesis, MetAP-2 binding affinity and structural analysis of reversible MetAP-2 inhibitors. Optimization of enzymatic activity of screening hit 10 (IC50: 1 μM) led to the most potent compound 27 (IC50: 0.038 μM), with a concomitant improvement in LLE from 2.1 to 4.2. Structural analysis of these MetAP-2 inhibitors revealed an unprecedented conformation of the His339 side-chain imidazole ring being co-planar sandwiched between the imidazole of His331 and the aryl-ether moiety, which is bound to the purine scaffold. Systematic alteration and reduction of H-bonding capability of this metal binding moiety induced an unexpected 180° flip for the triazolo[1,5-a]pyrimdine bicyclic template. 相似文献
17.
Hans-Peter Baum J?rg Reichrath Andrea Theobald Gudrun Schock 《The Histochemical journal》1994,26(12):929-933
Summary In contrast to that in paraffin-embedded tissue, the reactivity of monoclonal PCNA antibody PC10 on cryostat sections requires
a special fixation procedure as the target epitope is seemingly not accessible to its antibody. A panel of 18 fixation protocols
was investigated. Chilled methanol or acetone, or PLP (paraformaldehyde-lysine-periodate) was found to be unsuitable for skin
preparations. A two-step fixation protocol was developed for normal skin and basal cell carcinomas. They were fixed first
in 3.4% buffered formaldehyde, followed by fixation in 2:1 v/v ethanol-acetic acid. Following this fixation regime, cryostat
sections displayed the same PCNA/PC10 labelling pattern as paraffin sections of formalin-fixed tissue. 相似文献
18.
Reducing maintenance metabolism by metabolic engineering of respiration improves riboflavin production by Bacillus subtilis 总被引:2,自引:0,他引:2
We present redirection of electron flow to more efficient proton pumping branches within respiratory chains as a generally applicable metabolic engineering strategy, which tailors microbial metabolism to the specific requirements of high cell density processes by improving product and biomass yields. For the example of riboflavin production by Bacillus subtilis, we reduced the rate of maintenance metabolism by about 40% in a cytochrome bd oxidase knockout mutant. Since the putative Yth and the caa(3) oxidases were of minor importance, the most likely explanation for this improvement is translocation of two protons per transported electron via the remaining cytochrome aa(3) oxidase, instead of only one proton via the bd oxidase. The reduction of maintenance metabolism, in turn, significantly improved the yield of recombinant riboflavin and B. subtilis biomass in fed-batch cultures. 相似文献
19.
Wollmann Y Schmidt U Wieland GD Zipfel PF Saluz HP Hänel F 《Journal of cellular biochemistry》2007,102(1):171-182
We investigated the physical association of the DNA topoisomerase IIbeta binding protein 1 (TopBP1), involved in DNA replication and repair but also in regulation of apoptosis, with poly(ADP-ribose) polymerase-1 (PARP-1). This enzyme plays a crucial role in DNA repair and interacts with many DNA replication/repair factors. It was shown that the sixth BRCA1 C-terminal (BRCT) domain of TopBP1 interacts with a protein fragment of PARP-1 in vitro containing the DNA-binding and the automodification domains. More significantly, the in vivo interaction of endogenous TopBP1 and PARP-1 proteins could be shown in HeLa-S3 cells by co-immunoprecipitation. TopBP1 and PARP-1 are localized within overlapping regions in the nucleus of HeLa-S3 cells as shown by immunofluorescence. Exposure to UVB light slightly enhanced the interaction between both proteins. Furthermore, TopBP1 was detected in nuclear regions where poly(ADP-ribose) (PAR) synthesis takes place and is ADP-ribosylated by PARP-1. Finally, cellular (ADP-ribosyl)ating activity impairs binding of TopBP1 to Myc-interacting zinc finger protein-1 (Miz-1). The results indicate an influence of post-translational modifications of TopBP1 on its function during DNA repair. 相似文献
20.
Molecular identification of two strains of third-stage larvae of Contracaecum rudolphii sensu lato (Nematoda: Anisakidae) from fish in Poland 总被引:1,自引:0,他引:1
Contracaecum sp. larvae (L3) from fish were identified using nucleotide sequences of the internal transcribed spacers ITS-1 and ITS-2 of the ribosomal DNA. The nematode larvae originated from fish in a freshwater situation (crucian carp Carassius carassius, from Selment Wielki Lake in Mazury, northeastern Poland) and a brackish-water region (Caspian round goby Neogobius melanostomus from the Baltic Sea, Gdafisk Bay at the Polish coast). Two strains (Contracaecum rudolphii A and B) of Contracaecum rudolphii senso lato, a parasite common at the adult stage in fish-eating birds, were identified. In fish from the freshwater site, only the strain temporarily designated C. rudolphii B was identified; in the brackish-water region, both strains were found, suggesting that fish serve as paratenic host for both genotypes. Contracaecum rudolphii sensu lato has been recorded in several species of fish-eating birds in Poland, particularly in the great cormorant, Phalacrocorax carbo, in which the abundance is highest. The results, although based on a restricted number of larvae, suggest that the life cycles of both genotypes can be completed in the Polish region and that at least one of them, C. rudolphii B, can develop both in fresh and brackish water. 相似文献